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Elbert JA, Schuh AJ, Amman BR, Guito JC, Graziano JC, Sealy TK, Howerth EW, Towner JS. Characterization of Ravn virus viral shedding dynamics in experimentally infected Egyptian rousette bats ( Rousettus aegypticus). J Virol 2025; 99:e0004525. [PMID: 40265897 PMCID: PMC12090798 DOI: 10.1128/jvi.00045-25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2025] [Accepted: 03/27/2025] [Indexed: 04/24/2025] Open
Abstract
Marburg virus (MARV) and Ravn virus (RAVV), the only two known members of the species Orthomarburgvirus marburgense (family Filoviridae), are causative agents of Marburg virus disease, a severe viral disease that typically emerges in sub-Saharan Africa and is characterized by human-to-human transmission and high case fatalities. Despite the robust characterization of MARV experimental infection in Egyptian rousette bats (ERBs; Rousettus aegyptiacus; common name: Egyptian rousettes), a natural MARV reservoir, experimental infection with RAVV in ERBs has not been completed. Here, we experimentally infect 12 ERBs with RAVV and quantify viral loads in blood, oral swabs, and rectal swabs over a 21-day timeline with serological and cumulative shedding data and baseline clinical parameters. Compared to previously described experimental MARV infection in ERBs, these bats experimentally inoculated with RAVV had significantly higher and prolonged rectal viral shedding loads, as well as significantly prolonged oral shedding and higher peak viremia. All ERBs seroconverted by 21 days post-infection. Additionally, all ERBs demonstrated marked heterogeneity in RAVV viral shedding loads consistent with the Pareto Principle and viral "supershedders." Our results introduce the possibility of variation in transmission dynamics and subsequent spillover differences between RAVV and MARV.IMPORTANCERavn virus, along with Marburg virus, causes severe viral disease in humans with high fatality but little to no clinical disease in its reservoir host, the Egyptian rousette bat. Our findings provide important insights into how Ravn virus behaves in its natural reservoir host, showing that Ravn virus infection followed a similar timeline to Marburg virus infection, with virus detected in blood, saliva, and feces. However, Ravn virus-infected bats had higher levels of viral shedding and shed the virus for a longer period, particularly in feces, compared to Marburg virus. These differences in viral shedding may impact the spread of the virus within bat populations and potentially alter the likelihood of spillover into humans, non-human primates, and other animal species. These insights are crucial for understanding Ravn virus maintenance in its bat reservoir and improving our ability to mitigate or prevent future human outbreaks.
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Affiliation(s)
- Jessica A. Elbert
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Amy J. Schuh
- Viral Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, United States Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- USA Public Health Service Commissioned Corps, Rockville, Maryland, USA
| | - Brian R. Amman
- Viral Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, United States Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Jonathan C. Guito
- Viral Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, United States Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - James C. Graziano
- Viral Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, United States Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Tara K. Sealy
- Viral Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, United States Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Elizabeth W. Howerth
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Jonathan S. Towner
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
- Viral Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, United States Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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Kang JS, Zhou K, Wang H, Tang S, Lyles KVM, Luo M, Zhou ZH. Architectural organization and in situ fusion protein structure of lymphocytic choriomeningitis virus. J Virol 2024; 98:e0064024. [PMID: 39329471 PMCID: PMC11495036 DOI: 10.1128/jvi.00640-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Accepted: 08/09/2024] [Indexed: 09/28/2024] Open
Abstract
Arenaviruses exist globally and can cause hemorrhagic fever and neurological diseases, exemplified by the zoonotic pathogen lymphocytic choriomeningitis virus (LCMV). The structures of individual LCMV proteins or their fragments have been reported, but the architectural organization and the nucleocapsid assembly mechanism remain elusive. Importantly, the in situ structure of the arenavirus fusion protein complex (glycoprotein complex, GPC) as present on the virion prior to fusion, particularly with its integral stable signal peptide (SSP), has not been shown, hindering efforts such as structure-based vaccine design. Here, we have determined the in situ structure of LCMV proteins and their architectural organization in the virion by cryogenic electron tomography. The tomograms reveal the global distribution of GPC, matrix protein Z, and the contact points between the viral envelope and nucleocapsid. Subtomogram averaging yielded the in situ structure of the mature GPC with its transmembrane domain intact, revealing the GP2-SSP interface and the endodomain of GP2. The number of RNA-dependent RNA polymerase L molecules packaged within each virion varies, adding new perspectives to the infection mechanism. Together, these results delineate the structural organization of LCMV and offer new insights into its mechanism of LCMV maturation, egress, and cell entry. IMPORTANCE The impact of COVID-19 on public health has highlighted the importance of understanding zoonotic pathogens. Lymphocytic choriomeningitis virus (LCMV) is a rodent-borne human pathogen that causes hemorrhagic fever. Herein, we describe the in situ structure of LCMV proteins and their architectural organization on the viral envelope and around the nucleocapsid. The virion structure reveals the distribution of the surface glycoprotein complex (GPC) and the contact points between the viral envelope and the underlying matrix protein, as well as the association with the nucleocapsid. The morphology and sizes of virions, as well as the number of RNA polymerase L inside each virion vary greatly, highlighting the fast-changing nature of LCMV. A comparison between the in situ GPC trimeric structure and prior ectodomain structures identifies the transmembrane and endo domains of GPC and key interactions among its subunits. The work provides new insights into LCMV assembly and informs future structure-guided vaccine design.
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Affiliation(s)
- Joon S. Kang
- California NanoSystems Institute, University of California, Los Angeles, California, USA
- Molecular Biology Institute, University of California, Los Angeles, California, USA
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, California, USA
| | - Kang Zhou
- California NanoSystems Institute, University of California, Los Angeles, California, USA
| | - Hui Wang
- California NanoSystems Institute, University of California, Los Angeles, California, USA
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, California, USA
| | - Sijia Tang
- Institute of Biomedical Sciences, Georgia State University, Atlanta, Georgia, USA
| | | | - Ming Luo
- Department of Chemistry, Georgia State University, Atlanta, Georgia, USA
- Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA
| | - Z. Hong Zhou
- California NanoSystems Institute, University of California, Los Angeles, California, USA
- Molecular Biology Institute, University of California, Los Angeles, California, USA
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, California, USA
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Qi R, Fu R, Lei X, He J, Jiang Y, Zhang L, Wu Y, Wang S, Guo X, Chen F, Nie M, Yang M, Chen Y, Zeng J, Xu J, Xiong H, Fang M, Que Y, Yao Y, Wang Y, Cao J, Ye H, Zhang Y, Zheng Z, Cheng T, Zhang J, Lin X, Yuan Q, Zhang T, Xia N. Therapeutic vaccine-induced plasma cell differentiation is defective in the presence of persistently high HBsAg levels. J Hepatol 2024; 80:714-729. [PMID: 38336348 DOI: 10.1016/j.jhep.2023.12.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 12/15/2023] [Accepted: 12/29/2023] [Indexed: 02/12/2024]
Abstract
BACKGROUND & AIMS Mechanisms behind the impaired response of antigen-specific B cells to therapeutic vaccination in chronic hepatitis B virus (HBV) infection remain unclear. The development of vaccines or strategies to overcome this obstacle is vital for advancing the management of chronic hepatitis B. METHODS A mouse model, denominated as E6F6-B, was engineered to feature a knock-in of a B-cell receptor (BCR) that specifically recognizes HBsAg. This model served as a valuable tool for investigating the temporal and spatial dynamics of humoral responses following therapeutic vaccination under continuous antigen exposure. Using a suite of immunological techniques, we elucidated the differentiation trajectory of HBsAg-specific B cells post-therapeutic vaccination in HBV carrier mice. RESULTS Utilizing the E6F6-B transfer model, we observed a marked decline in antibody-secreting cells 2 weeks after vaccination. A dysfunctional and atypical pre-plasma cell population (BLIMP-1+ IRF4+ CD40- CD138- BCMA-) emerged, manifested by sustained BCR signaling. By deploying an antibody to purge persistent HBsAg, we effectively prompted the therapeutic vaccine to provoke conventional plasma cell differentiation. This resulted in an enhanced anti-HBs antibody response and facilitated HBsAg clearance. CONCLUSIONS Sustained high levels of HBsAg limit the ability of therapeutic hepatitis B vaccines to induce the canonical plasma cell differentiation necessary for anti-HBs antibody production. Employing a strategy combining antibodies with vaccines can surmount this altered humoral response associated with atypical pre-plasma cells, leading to improved therapeutic efficacy in HBV carrier mice. IMPACT AND IMPLICATIONS Therapeutic vaccines aimed at combatting HBV encounter suboptimal humoral responses in clinical settings, and the mechanisms impeding their effectiveness have remained obscure. Our research, utilizing the innovative E6F6-B mouse transfer model, reveals that the persistence of HBsAg can lead to the emergence of an atypical pre-plasma cell population, which proves to be relevant to the potency of therapeutic HBV vaccines. Targeting the aberrant differentiation process of these atypical pre-plasma cells stands out as a critical strategy to amplify the humoral response elicited by HBV therapeutic vaccines in carrier mouse models. This discovery suggests a compelling avenue for further study in the context of human chronic hepatitis B. Encouragingly, our findings indicate that synergistic therapy combining HBV-specific antibodies with vaccines offers a promising approach that could significantly advance the pursuit of a functional cure for HBV.
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Affiliation(s)
- Ruoyao Qi
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Rao Fu
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Xing Lei
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Jinhang He
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Yao Jiang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Liang Zhang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Yangtao Wu
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Siling Wang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Xueran Guo
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Feng Chen
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Meifeng Nie
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Man Yang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Yiyi Chen
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Jing Zeng
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China; Department of clinical laboratory, Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen 361102, Fujian, China
| | - Jingjing Xu
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China
| | - Hualong Xiong
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Mujin Fang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Yuqiong Que
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Youliang Yao
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Yingbin Wang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Jiali Cao
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China; Department of clinical laboratory, Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen 361102, Fujian, China
| | - Huiming Ye
- Department of clinical laboratory, Women and Children's Hospital, School of Medicine, Xiamen University, Xiamen 361102, Fujian, China
| | - Yali Zhang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Zizheng Zheng
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Tong Cheng
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Jun Zhang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China
| | - Xu Lin
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.
| | - Quan Yuan
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China.
| | - Tianying Zhang
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China.
| | - Ningshao Xia
- State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Public Health and School of Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; National Institute of Diagnostics and Vaccine Development in Infectious Diseases, State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, NMPA Key Laboratory for Research and Evaluation of Infectious Disease Diagnostic Technology, Xiamen University, Xiamen 361102, Fujian, China.
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Johnson DM, Khakhum N, Wang M, Warner NL, Jokinen JD, Comer JE, Lukashevich IS. Pathogenic and Apathogenic Strains of Lymphocytic Choriomeningitis Virus Have Distinct Entry and Innate Immune Activation Pathways. Viruses 2024; 16:635. [PMID: 38675975 PMCID: PMC11053560 DOI: 10.3390/v16040635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/08/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024] Open
Abstract
Lymphocytic choriomeningitis virus (LCMV) and Lassa virus (LASV) share many genetic and biological features including subtle differences between pathogenic and apathogenic strains. Despite remarkable genetic similarity, the viscerotropic WE strain of LCMV causes a fatal LASV fever-like hepatitis in non-human primates (NHPs) while the mouse-adapted Armstrong (ARM) strain of LCMV is deeply attenuated in NHPs and can vaccinate against LCMV-WE challenge. Here, we demonstrate that internalization of WE is more sensitive to the depletion of membrane cholesterol than ARM infection while ARM infection is more reliant on endosomal acidification. LCMV-ARM induces robust NF-κB and interferon response factor (IRF) activation while LCMV-WE seems to avoid early innate sensing and failed to induce strong NF-κB and IRF responses in dual-reporter monocyte and epithelial cells. Toll-like receptor 2 (TLR-2) signaling appears to play a critical role in NF-κB activation and the silencing of TLR-2 shuts down IL-6 production in ARM but not in WE-infected cells. Pathogenic LCMV-WE infection is poorly recognized in early endosomes and failed to induce TLR-2/Mal-dependent pro-inflammatory cytokines. Following infection, Interleukin-1 receptor-associated kinase 1 (IRAK-1) expression is diminished in LCMV-ARM- but not LCMV-WE-infected cells, which indicates it is likely involved in the LCMV-ARM NF-κB activation. By confocal microscopy, ARM and WE strains have similar intracellular trafficking although LCMV-ARM infection appears to coincide with greater co-localization of early endosome marker EEA1 with TLR-2. Both strains co-localize with Rab-7, a late endosome marker, but the interaction with LCMV-WE seems to be more prolonged. These findings suggest that LCMV-ARM's intracellular trafficking pathway may facilitate interaction with innate immune sensors, which promotes the induction of effective innate and adaptive immune responses.
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Affiliation(s)
- Dylan M. Johnson
- Center for Predictive Medicine for Biodefense and Emerging Infectious Diseases, Louisville, KY 94202, USA (I.S.L.)
- Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY 94202, USA
- Galveston National Laboratory, Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77550, USA; (N.K.); (J.E.C.)
- Sandia National Laboratories, Department of Biotechnology & Bioengineering, Livermore, CA 94550, USA
| | - Nittaya Khakhum
- Galveston National Laboratory, Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77550, USA; (N.K.); (J.E.C.)
| | - Min Wang
- Department of Pharmacology and Toxicology, University of Louisville Health Sciences Center, Louisville, KY 94202, USA;
| | - Nikole L. Warner
- Center for Predictive Medicine for Biodefense and Emerging Infectious Diseases, Louisville, KY 94202, USA (I.S.L.)
- Department of Microbiology and Immunology, University of Louisville Health Sciences Center, Louisville, KY 94202, USA
| | - Jenny D. Jokinen
- Center for Predictive Medicine for Biodefense and Emerging Infectious Diseases, Louisville, KY 94202, USA (I.S.L.)
- Department of Pharmacology and Toxicology, University of Louisville Health Sciences Center, Louisville, KY 94202, USA;
| | - Jason E. Comer
- Galveston National Laboratory, Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX 77550, USA; (N.K.); (J.E.C.)
| | - Igor S. Lukashevich
- Center for Predictive Medicine for Biodefense and Emerging Infectious Diseases, Louisville, KY 94202, USA (I.S.L.)
- Department of Pharmacology and Toxicology, University of Louisville Health Sciences Center, Louisville, KY 94202, USA;
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5
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Ware BC, Parks MG, da Silva MOL, Morrison TE. Chikungunya virus infection disrupts MHC-I antigen presentation via nonstructural protein 2. PLoS Pathog 2024; 20:e1011794. [PMID: 38483968 DOI: 10.1371/journal.ppat.1011794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 03/26/2024] [Accepted: 03/04/2024] [Indexed: 03/26/2024] Open
Abstract
Infection by chikungunya virus (CHIKV), a mosquito-borne alphavirus, causes severe polyarthralgia and polymyalgia, which can last in some people for months to years. Chronic CHIKV disease signs and symptoms are associated with the persistence of viral nucleic acid and antigen in tissues. Like humans and nonhuman primates, CHIKV infection in mice results in the development of robust adaptive antiviral immune responses. Despite this, joint tissue fibroblasts survive CHIKV infection and can support persistent viral replication, suggesting that they escape immune surveillance. Here, using a recombinant CHIKV strain encoding the fluorescent protein VENUS with an embedded CD8+ T cell epitope, SIINFEKL, we observed a marked loss of both MHC class I (MHC-I) surface expression and antigen presentation by CHIKV-infected joint tissue fibroblasts. Both in vivo and ex vivo infected joint tissue fibroblasts displayed reduced cell surface levels of H2-Kb and H2-Db MHC-I proteins while maintaining similar levels of other cell surface proteins. Mutations within the methyl transferase-like domain of the CHIKV nonstructural protein 2 (nsP2) increased MHC-I cell surface expression and antigen presentation efficiency by CHIKV-infected cells. Moreover, expression of WT nsP2 alone, but not nsP2 with mutations in the methyltransferase-like domain, resulted in decreased MHC-I antigen presentation efficiency. MHC-I surface expression and antigen presentation was rescued by replacing VENUS-SIINFEKL with SIINFEKL tethered to β2-microglobulin in the CHIKV genome, which bypasses the requirement for peptide processing and TAP-mediated peptide transport into the endoplasmic reticulum. Collectively, this work suggests that CHIKV escapes the surveillance of antiviral CD8+ T cells, in part, by nsP2-mediated disruption of MHC-I antigen presentation.
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Affiliation(s)
- Brian C Ware
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - M Guston Parks
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Mariana O L da Silva
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
- Instituto de Microbiologia Paulo de Goes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thomas E Morrison
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
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Jamaleddine H, Rogers D, Perreault G, Postat J, Patel D, Mandl JN, Khadra A. Chronic infection control relies on T cells with lower foreign antigen binding strength generated by N-nucleotide diversity. PLoS Biol 2024; 22:e3002465. [PMID: 38300945 PMCID: PMC10833529 DOI: 10.1371/journal.pbio.3002465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 12/08/2023] [Indexed: 02/03/2024] Open
Abstract
The breadth of pathogens to which T cells can respond is determined by the T cell receptors (TCRs) present in an individual's repertoire. Although more than 90% of the sequence diversity among TCRs is generated by terminal deoxynucleotidyl transferase (TdT)-mediated N-nucleotide addition during V(D)J recombination, the benefit of TdT-altered TCRs remains unclear. Here, we computationally and experimentally investigated whether TCRs with higher N-nucleotide diversity via TdT make distinct contributions to acute or chronic pathogen control specifically through the inclusion of TCRs with lower antigen binding strengths (i.e., lower reactivity to peptide-major histocompatibility complex (pMHC)). When T cells with high pMHC reactivity have a greater propensity to become functionally exhausted than those of low pMHC reactivity, our computational model predicts a shift toward T cells with low pMHC reactivity over time during chronic, but not acute, infections. This TCR-affinity shift is critical, as the elimination of T cells with lower pMHC reactivity in silico substantially increased the time to clear a chronic infection, while acute infection control remained largely unchanged. Corroborating an affinity-centric benefit for TCR diversification via TdT, we found evidence that TdT-deficient TCR repertoires possess fewer T cells with weaker pMHC binding strengths in vivo and showed that TdT-deficient mice infected with a chronic, but not an acute, viral pathogen led to protracted viral clearance. In contrast, in the case of a chronic fungal pathogen where T cells fail to clear the infection, both our computational model and experimental data showed that TdT-diversified TCR repertoires conferred no additional protection to the hosts. Taken together, our in silico and in vivo data suggest that TdT-mediated TCR diversity is of particular benefit for the eventual resolution of prolonged pathogen replication through the inclusion of TCRs with lower foreign antigen binding strengths.
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Affiliation(s)
| | - Dakota Rogers
- Department of Physiology, McGill University, Montreal, Quebec, Canada
- McGill University Research Centre on Complex Traits, Montreal, Quebec, Canada
| | - Geneviève Perreault
- McGill University Research Centre on Complex Traits, Montreal, Quebec, Canada
| | - Jérémy Postat
- Department of Physiology, McGill University, Montreal, Quebec, Canada
- McGill University Research Centre on Complex Traits, Montreal, Quebec, Canada
| | - Dhanesh Patel
- Department of Physiology, McGill University, Montreal, Quebec, Canada
- McGill University Research Centre on Complex Traits, Montreal, Quebec, Canada
| | - Judith N. Mandl
- Department of Physiology, McGill University, Montreal, Quebec, Canada
- McGill University Research Centre on Complex Traits, Montreal, Quebec, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
| | - Anmar Khadra
- Department of Physiology, McGill University, Montreal, Quebec, Canada
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7
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Uribe FR, González VPI, Kalergis AM, Soto JA, Bohmwald K. Understanding the Neurotrophic Virus Mechanisms and Their Potential Effect on Systemic Lupus Erythematosus Development. Brain Sci 2024; 14:59. [PMID: 38248274 PMCID: PMC10813552 DOI: 10.3390/brainsci14010059] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/24/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
Central nervous system (CNS) pathologies are a public health concern, with viral infections one of their principal causes. These viruses are known as neurotropic pathogens, characterized by their ability to infiltrate the CNS and thus interact with various cell populations, inducing several diseases. The immune response elicited by neurotropic viruses in the CNS is commanded mainly by microglia, which, together with other local cells, can secrete inflammatory cytokines to fight the infection. The most relevant neurotropic viruses are adenovirus (AdV), cytomegalovirus (CMV), enterovirus (EV), Epstein-Barr Virus (EBV), herpes simplex virus type 1 (HSV-1), and herpes simplex virus type 2 (HSV-2), lymphocytic choriomeningitis virus (LCMV), and the newly discovered SARS-CoV-2. Several studies have associated a viral infection with systemic lupus erythematosus (SLE) and neuropsychiatric lupus (NPSLE) manifestations. This article will review the knowledge about viral infections, CNS pathologies, and the immune response against them. Also, it allows us to understand the relevance of the different viral proteins in developing neuronal pathologies, SLE and NPSLE.
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Affiliation(s)
- Felipe R. Uribe
- Millennium Institute on Immunology and Immunotherapy, Laboratorio de Inmunología Traslacional, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago 8370146, Chile; (F.R.U.); (V.P.I.G.)
| | - Valentina P. I. González
- Millennium Institute on Immunology and Immunotherapy, Laboratorio de Inmunología Traslacional, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago 8370146, Chile; (F.R.U.); (V.P.I.G.)
| | - Alexis M. Kalergis
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8330025, Chile;
- Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Jorge A. Soto
- Millennium Institute on Immunology and Immunotherapy, Laboratorio de Inmunología Traslacional, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago 8370146, Chile; (F.R.U.); (V.P.I.G.)
| | - Karen Bohmwald
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma, Santiago 8910060, Chile
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8
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Ware BC, Parks MG, Morrison TE. Chikungunya virus infection disrupts MHC-I antigen presentation via nonstructural protein 2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.03.565436. [PMID: 37961400 PMCID: PMC10635105 DOI: 10.1101/2023.11.03.565436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Infection by chikungunya virus (CHIKV), a mosquito-borne alphavirus, causes severe polyarthralgia and polymyalgia, which can last in some people for months to years. Chronic CHIKV disease signs and symptoms are associated with the persistence of viral nucleic acid and antigen in tissues. Like humans and nonhuman primates, CHIKV infection in mice results in the development of robust adaptive antiviral immune responses. Despite this, joint tissue fibroblasts survive CHIKV infection and can support persistent viral replication, suggesting that they escape immune surveillance. Here, using a recombinant CHIKV strain encoding a chimeric protein of VENUS fused to a CD8+ T cell epitope, SIINFEKL, we observed a marked loss of both MHC class I (MHC-I) surface expression and antigen presentation by CHIKV-infected joint tissue fibroblasts. Both in vivo and ex vivo infected joint tissue fibroblasts displayed reduced cell surface levels of H2-Kb and H2-Db MHC proteins while maintaining similar levels of other cell surface proteins. Mutations within the methyl transferase-like domain of the CHIKV nonstructural protein 2 (nsP2) increased MHC-I cell surface expression and antigen presentation efficiency by CHIKV-infected cells. Moreover, expression of WT nsP2 alone, but not nsP2 with mutations in the methyltransferase-like domain, resulted in decreased MHC-I antigen presentation efficiency. MHC-I surface expression and antigen presentation could be rescued by replacing VENUS-SIINFEKL with SIINFEKL tethered to β2-microglobulin in the CHIKV genome, which bypasses the need for peptide processing and TAP-mediated peptide transport into the endoplasmic reticulum. Collectively, this work suggests that CHIKV escapes the surveillance of antiviral CD8+ T cells, in part, by nsP2-mediated disruption of MHC-I antigen presentation.
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Affiliation(s)
- Brian C. Ware
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - M. Guston Parks
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Thomas E. Morrison
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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9
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Moon-Walker A, Zhang Z, Zyla DS, Buck TK, Li H, Diaz Avalos R, Schendel SL, Hastie KM, Crotty S, Saphire EO. Structural basis for antibody-mediated neutralization of lymphocytic choriomeningitis virus. Cell Chem Biol 2023; 30:403-411.e4. [PMID: 36990092 PMCID: PMC11090681 DOI: 10.1016/j.chembiol.2023.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 12/23/2022] [Accepted: 03/08/2023] [Indexed: 03/30/2023]
Abstract
The mammarenavirus lymphocytic choriomeningitis virus (LCMV) is a globally distributed zoonotic pathogen that can be lethal in immunocompromised patients and can cause severe birth defects if acquired during pregnancy. The structure of the trimeric surface glycoprotein, essential for entry, vaccine design, and antibody neutralization, remains unknown. Here, we present the cryoelectron microscopy (cryo-EM) structure of the LCMV surface glycoprotein (GP) in its trimeric pre-fusion assembly both alone and in complex with a rationally engineered monoclonal neutralizing antibody termed 18.5C-M28 (M28). Additionally, we show that passive administration of M28, either as a prophylactic or therapeutic, protects mice from LCMV clone 13 (LCMVcl13) challenge. Our study illuminates not only the overall structural organization of LCMV GP and the mechanism for its inhibition by M28 but also presents a promising therapeutic candidate to prevent severe or fatal disease in individuals who are at risk of infection by a virus that poses a threat worldwide.
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Affiliation(s)
- Alex Moon-Walker
- La Jolla Institute for Immunology; La Jolla, CA 92037, USA; Program in Virology, Harvard Medical School, Boston, MA 02115, USA; Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, MI 63110, USA
| | - Zeli Zhang
- La Jolla Institute for Immunology; La Jolla, CA 92037, USA
| | - Dawid S Zyla
- La Jolla Institute for Immunology; La Jolla, CA 92037, USA
| | - Tierra K Buck
- La Jolla Institute for Immunology; La Jolla, CA 92037, USA; Program in Virology, Harvard Medical School, Boston, MA 02115, USA
| | - Haoyang Li
- La Jolla Institute for Immunology; La Jolla, CA 92037, USA
| | | | | | | | - Shane Crotty
- La Jolla Institute for Immunology; La Jolla, CA 92037, USA.
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10
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Mammarenavirus Genetic Diversity and Its Biological Implications. Curr Top Microbiol Immunol 2023; 439:265-303. [PMID: 36592249 DOI: 10.1007/978-3-031-15640-3_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Members of the family Arenaviridae are classified into four genera: Antennavirus, Hartmanivirus, Mammarenavirus, and Reptarenavirus. Reptarenaviruses and hartmaniviruses infect (captive) snakes and have been shown to cause boid inclusion body disease (BIBD). Antennaviruses have genomes consisting of 3, rather than 2, segments, and were discovered in actinopterygian fish by next-generation sequencing but no biological isolate has been reported yet. The hosts of mammarenaviruses are mainly rodents and infections are generally asymptomatic. Current knowledge about the biology of reptarenaviruses, hartmaniviruses, and antennaviruses is very limited and their zoonotic potential is unknown. In contrast, some mammarenaviruses are associated with zoonotic events that pose a threat to human health. This review will focus on mammarenavirus genetic diversity and its biological implications. Some mammarenaviruses including lymphocytic choriomeningitis virus (LCMV) are excellent experimental model systems for the investigation of acute and persistent viral infections, whereas others including Lassa (LASV) and Junin (JUNV) viruses, the causative agents of Lassa fever (LF) and Argentine hemorrhagic fever (AHF), respectively, are important human pathogens. Mammarenaviruses were thought to have high degree of intra-and inter-species amino acid sequence identities, but recent evidence has revealed a high degree of mammarenavirus genetic diversity in the field. Moreover, closely related mammarenavirus can display dramatic phenotypic differences in vivo. These findings support a role of genetic variability in mammarenavirus adaptability and pathogenesis. Here, we will review the molecular biology of mammarenaviruses, phylogeny, and evolution, as well as the quasispecies dynamics of mammarenavirus populations and their biological implications.
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11
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Morodomi Y, Kanaji S, Sullivan BM, Zarpellon A, Orje JN, Won E, Shapiro R, Yang XL, Ruf W, Schimmel P, Ruggeri ZM, Kanaji T. Inflammatory platelet production stimulated by tyrosyl-tRNA synthetase mimicking viral infection. Proc Natl Acad Sci U S A 2022; 119:e2212659119. [PMID: 36409883 PMCID: PMC9860251 DOI: 10.1073/pnas.2212659119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 10/20/2022] [Indexed: 11/22/2022] Open
Abstract
Platelets play a role not only in hemostasis and thrombosis, but also in inflammation and innate immunity. We previously reported that an activated form of tyrosyl-tRNA synthetase (YRSACT) has an extratranslational activity that enhances megakaryopoiesis and platelet production in mice. Here, we report that YRSACT mimics inflammatory stress inducing a unique megakaryocyte (MK) population with stem cell (Sca1) and myeloid (F4/80) markers through a mechanism dependent on Toll-like receptor (TLR) activation and type I interferon (IFN-I) signaling. This mimicry of inflammatory stress by YRSACT was studied in mice infected by lymphocytic choriomeningitis virus (LCMV). Using Sca1/EGFP transgenic mice, we demonstrated that IFN-I induced by YRSACT or LCMV infection suppressed normal hematopoiesis while activating an alternative pathway of thrombopoiesis. Platelets of inflammatory origin (Sca1/EGFP+) were a relevant proportion of those circulating during recovery from thrombocytopenia. Analysis of these "inflammatory" MKs and platelets suggested their origin in myeloid/MK-biased hematopoietic stem cells (HSCs) that bypassed the classical MK-erythroid progenitor (MEP) pathway to replenish platelets and promote recovery from thrombocytopenia. Notably, inflammatory platelets displayed enhanced agonist-induced activation and procoagulant activities. Moreover, myeloid/MK-biased progenitors and MKs were mobilized from the bone marrow, as evidenced by their presence in the lung microvasculature within fibrin-containing microthrombi. Our results define the function of YRSACT in platelet generation and contribute to elucidate platelet alterations in number and function during viral infection.
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Affiliation(s)
- Yosuke Morodomi
- Department of Molecular Medicine, MERU-Roon Research Center on Vascular Biology, The Scripps Research Institute, La Jolla, CA92037
- The Scripps Laboratories for tRNA Synthetase Research, Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
| | - Sachiko Kanaji
- Department of Molecular Medicine, MERU-Roon Research Center on Vascular Biology, The Scripps Research Institute, La Jolla, CA92037
- The Scripps Laboratories for tRNA Synthetase Research, Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
| | - Brian M. Sullivan
- Viral-Immunobiology Laboratory, Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA92037
| | | | - Jennifer N. Orje
- Department of Molecular Medicine, MERU-Roon Research Center on Vascular Biology, The Scripps Research Institute, La Jolla, CA92037
- MERU-VasImmune, Inc., San Diego, CA92121
| | - Eric Won
- Department of Molecular Medicine, MERU-Roon Research Center on Vascular Biology, The Scripps Research Institute, La Jolla, CA92037
- Department of Hematology and Oncology, University of California, San Diego, CA92093
- Rady Children’s Hospital, San Diego, CA92123
| | - Ryan Shapiro
- The Scripps Laboratories for tRNA Synthetase Research, Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
| | - Xiang-Lei Yang
- The Scripps Laboratories for tRNA Synthetase Research, Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
| | - Wolfram Ruf
- Center for Thrombosis and Hemostasis, University Medical Center of the Johannes Gutenberg University, 55128Germany
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA92037
| | - Paul Schimmel
- The Scripps Laboratories for tRNA Synthetase Research, Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
| | - Zaverio M. Ruggeri
- Department of Molecular Medicine, MERU-Roon Research Center on Vascular Biology, The Scripps Research Institute, La Jolla, CA92037
- MERU-VasImmune, Inc., San Diego, CA92121
| | - Taisuke Kanaji
- Department of Molecular Medicine, MERU-Roon Research Center on Vascular Biology, The Scripps Research Institute, La Jolla, CA92037
- The Scripps Laboratories for tRNA Synthetase Research, Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
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12
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Beura LK, Scott MC, Pierson MJ, Joag V, Wijeyesinghe S, Semler MR, Quarnstrom CF, Busman-Sahay K, Estes JD, Hamilton SE, Vezys V, O'Connor DH, Masopust D. Novel Lymphocytic Choriomeningitis Virus Strain Sustains Abundant Exhausted Progenitor CD8 T Cells without Systemic Viremia. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 209:1691-1702. [PMID: 36122933 PMCID: PMC9588727 DOI: 10.4049/jimmunol.2200320] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 08/21/2022] [Indexed: 01/04/2023]
Abstract
Lymphocytic choriomeningitis virus (LCMV) is the prototypic arenavirus and a natural mouse pathogen. LCMV-Armstrong, an acutely resolved strain, and LCMV-clone 13, a mutant that establishes chronic infection, have provided contrasting infection models that continue to inform the fundamental biology of T cell differentiation, regulation of exhaustion, and response to checkpoint blockade. In this study, we report the isolation and characterization of LCMV-Minnesota (LCMV-MN), which was naturally transmitted to laboratory mice upon cohousing with pet shop mice and shares 80-95% amino acid homology with previously characterized LCMV strains. Infection of laboratory mice with purified LCMV-MN resulted in viral persistence that was intermediate between LCMV-Armstrong and -clone 13, with widely disseminated viral replication and viremia that was controlled within 15-30 d, unless CD4 T cells were depleted prior to infection. LCMV-MN-responding CD8+ T cells biased differentiation toward the recently described programmed death-1 (PD-1)+CXCR5+Tim-3lo stemlike CD8+ T cell population (also referred to as progenitor exhausted T cells) that effectuates responses to PD-1 blockade checkpoint inhibition, a therapy that rejuvenates responses against chronic infections and cancer. This subset resembled previously characterized PD-1+TCF1+ stemlike CD8+ T cells by transcriptional, phenotypic, and functional assays, yet was atypically abundant. LCMV-MN may provide a tool to better understand the breadth of immune responses in different settings of chronic Ag stimulation as well as the ontogeny of progenitor exhausted T cells and the regulation of responsiveness to PD-1 blockade.
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Affiliation(s)
- Lalit K Beura
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI;
| | - Milcah C Scott
- Center for Immunology, University of Minnesota, Minneapolis, MN
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN
| | - Mark J Pierson
- Center for Immunology, University of Minnesota, Minneapolis, MN
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN
| | - Vineet Joag
- Center for Immunology, University of Minnesota, Minneapolis, MN
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN
| | - Sathi Wijeyesinghe
- Center for Immunology, University of Minnesota, Minneapolis, MN
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN
| | - Matthew R Semler
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI; and
| | - Clare F Quarnstrom
- Center for Immunology, University of Minnesota, Minneapolis, MN
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN
| | - Kathleen Busman-Sahay
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR
| | - Jacob D Estes
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR
| | - Sara E Hamilton
- Center for Immunology, University of Minnesota, Minneapolis, MN
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN
| | - Vaiva Vezys
- Center for Immunology, University of Minnesota, Minneapolis, MN
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN
| | - David H O'Connor
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI; and
| | - David Masopust
- Center for Immunology, University of Minnesota, Minneapolis, MN;
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN
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13
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Glutathione-dependent redox balance characterizes the distinct metabolic properties of follicular and marginal zone B cells. Nat Commun 2022; 13:1789. [PMID: 35379825 PMCID: PMC8980022 DOI: 10.1038/s41467-022-29426-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 03/11/2022] [Indexed: 11/13/2022] Open
Abstract
The metabolic principles underlying the differences between follicular and marginal zone B cells (FoB and MZB, respectively) are not well understood. Here we show, by studying mice with B cell-specific ablation of the catalytic subunit of glutamate cysteine ligase (Gclc), that glutathione synthesis affects homeostasis and differentiation of MZB to a larger extent than FoB, while glutathione-dependent redox control contributes to the metabolic dependencies of FoB. Specifically, Gclc ablation in FoB induces metabolic features of wild-type MZB such as increased ATP levels, glucose metabolism, mTOR activation, and protein synthesis. Furthermore, Gclc-deficient FoB have a block in the mitochondrial electron transport chain (ETC) due to diminished complex I and II activity and thereby accumulate the tricarboxylic acid cycle metabolite succinate. Finally, Gclc deficiency hampers FoB activation and antibody responses in vitro and in vivo, and induces susceptibility to viral infections. Our results thus suggest that Gclc is required to ensure the development of MZB, the mitochondrial ETC integrity in FoB, and the efficacy of antiviral humoral immunity. Follicular and marginal zone B (FoB and MZB, respectively) cells have divergent metabolic characteristics. Here the authors show that deficiency of glutamate cysteine ligase (Gclc), the enzyme for glutathione synthesis, differentially impacts FoB and MZB homeostasis, while specifically impeding FoB activation and downstream antiviral immunity.
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14
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Muhuri M, Levy DI, Schulz M, McCarty D, Gao G. Durability of transgene expression after rAAV gene therapy. Mol Ther 2022; 30:1364-1380. [PMID: 35283274 PMCID: PMC9077371 DOI: 10.1016/j.ymthe.2022.03.004] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/09/2022] [Accepted: 03/07/2022] [Indexed: 11/19/2022] Open
Abstract
Recombinant adeno-associated virus (rAAV) gene therapy has the potential to transform the lives of patients with certain genetic disorders by increasing or restoring function to affected tissues. Following the initial establishment of transgene expression, it is unknown how long the therapeutic effect will last, although animal and emerging human data show that expression can be maintained for more than 10 years. The durability of therapeutic response is key to long-term treatment success, especially since immune responses to rAAV vectors may prevent re-dosing with the same therapy. This review explores the non-immunological and immunological processes that may limit or improve durability and the strategies that can be used to increase the duration of the therapeutic effect.
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Affiliation(s)
- Manish Muhuri
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
| | | | | | | | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA; Li Weibo Institute for Rare Diseases Research, University of Massachusetts Medical School, Worcester, MA, USA.
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15
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Pennington H, Lee J. Lassa virus glycoprotein complex review: insights into its unique fusion machinery. Biosci Rep 2022; 42:BSR20211930. [PMID: 35088070 PMCID: PMC8844875 DOI: 10.1042/bsr20211930] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 11/17/2022] Open
Abstract
Lassa virus (LASV), an arenavirus endemic to West Africa, causes Lassa fever-a lethal hemorrhagic fever. Entry of LASV into the host cell is mediated by the glycoprotein complex (GPC), which is the only protein located on the viral surface and comprises three subunits: glycoprotein 1 (GP1), glycoprotein 2 (GP2), and a stable signal peptide (SSP). The LASV GPC is a class one viral fusion protein, akin to those found in viruses such as human immunodeficiency virus (HIV), influenza, Ebola virus (EBOV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). These viruses are enveloped and utilize membrane fusion to deliver their genetic material to the host cell. Like other class one fusion proteins, LASV-mediated membrane fusion occurs through an orchestrated sequence of conformational changes in its GPC. The receptor-binding subunit, GP1, first engages with a host cell receptor then undergoes a unique receptor switch upon delivery to the late endosome. The acidic pH and change in receptor result in the dissociation of GP1, exposing the fusion subunit, GP2, such that fusion can occur. These events ultimately lead to the formation of a fusion pore so that the LASV genetic material is released into the host cell. Interestingly, the mature GPC retains its SSP as a third subunit-a feature that is unique to arenaviruses. Additionally, the fusion domain contains two separate fusion peptides, instead of a standard singular fusion peptide. Here, we give a comprehensive review of the LASV GPC components and their unusual features.
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Affiliation(s)
- Hallie N. Pennington
- Department of Chemistry and Biochemistry, College of Computer, Mathematics, and Natural Science, University of Maryland College Park, College Park, MD 20740, U.S.A
| | - Jinwoo Lee
- Department of Chemistry and Biochemistry, College of Computer, Mathematics, and Natural Science, University of Maryland College Park, College Park, MD 20740, U.S.A
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16
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Katz M, Weinstein J, Eilon-Ashkenazy M, Gehring K, Cohen-Dvashi H, Elad N, Fleishman SJ, Diskin R. Structure and receptor recognition by the Lassa virus spike complex. Nature 2022; 603:174-179. [PMID: 35173332 DOI: 10.1038/s41586-022-04429-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 01/17/2022] [Indexed: 01/23/2023]
Abstract
Lassa virus (LASV) is a human pathogen, causing substantial morbidity and mortality1,2. Similar to other Arenaviridae, it presents a class-I spike complex on its surface that facilitates cell entry. The virus's cellular receptor is matriglycan, a linear carbohydrate that is present on α-dystroglycan3,4, but the molecular mechanism that LASV uses to recognize this glycan is unknown. In addition, LASV and other arenaviruses have a unique signal peptide that forms an integral and functionally important part of the mature spike5-8; yet the structure, function and topology of the signal peptide in the membrane remain uncertain9-11. Here we solve the structure of a complete native LASV spike complex, finding that the signal peptide crosses the membrane once and that its amino terminus is located in the extracellular region. Together with a double-sided domain-switching mechanism, the signal peptide helps to stabilize the spike complex in its native conformation. This structure reveals that the LASV spike complex is preloaded with matriglycan, suggesting the mechanism of binding and rationalizing receptor recognition by α-dystroglycan-tropic arenaviruses. This discovery further informs us about the mechanism of viral egress and may facilitate the rational design of novel therapeutics that exploit this binding site.
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Affiliation(s)
- Michael Katz
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Jonathan Weinstein
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Maayan Eilon-Ashkenazy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Katrin Gehring
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Hadas Cohen-Dvashi
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Nadav Elad
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Sarel J Fleishman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Ron Diskin
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
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17
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Chronic LCMV Infection Is Fortified with Versatile Tactics to Suppress Host T Cell Immunity and Establish Viral Persistence. Viruses 2021; 13:v13101951. [PMID: 34696381 PMCID: PMC8537583 DOI: 10.3390/v13101951] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/15/2021] [Accepted: 09/22/2021] [Indexed: 12/19/2022] Open
Abstract
Ever since the immune regulatory strains of lymphocytic choriomeningitis virus (LCMV), such as Clone 13, were isolated, LCMV infection of mice has served as a valuable model for the mechanistic study of viral immune suppression and virus persistence. The exhaustion of virus-specific T cells was demonstrated during LCMV infection, and the underlying mechanisms have been extensively investigated using LCMV infection in mouse models. In particular, the mechanism for gradual CD8+ T cell exhaustion at molecular and transcriptional levels has been investigated. These studies revealed crucial roles for inhibitory receptors, surface markers, regulatory cytokines, and transcription factors, including PD-1, PSGL-1, CXCR5, and TOX in the regulation of T cells. However, the action mode for CD4+ T cell suppression is largely unknown. Recently, sphingosine kinase 2 was proven to specifically repress CD4+ T cell proliferation and lead to LCMV persistence. As CD4+ T cell regulation was also known to be important for viral persistence, research to uncover the mechanism for CD4+ T cell repression could help us better understand how viruses launch and prolong their persistence. This review summarizes discoveries derived from the study of LCMV in regard to the mechanisms for T cell suppression and approaches for the termination of viral persistence with special emphasis on CD8+ T cells.
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18
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Szumilas N, Corneth OBJ, Lehmann CHK, Schmitt H, Cunz S, Cullen JG, Chu T, Marosan A, Mócsai A, Benes V, Zehn D, Dudziak D, Hendriks RW, Nitschke L. Siglec-H-Deficient Mice Show Enhanced Type I IFN Responses, but Do Not Develop Autoimmunity After Influenza or LCMV Infections. Front Immunol 2021; 12:698420. [PMID: 34497606 PMCID: PMC8419311 DOI: 10.3389/fimmu.2021.698420] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 07/27/2021] [Indexed: 12/02/2022] Open
Abstract
Siglec-H is a DAP12-associated receptor on plasmacytoid dendritic cells (pDCs) and microglia. Siglec-H inhibits TLR9-induced IFN-α production by pDCs. Previously, it was found that Siglec-H-deficient mice develop a lupus-like severe autoimmune disease after persistent murine cytomegalovirus (mCMV) infection. This was due to enhanced type I interferon responses, including IFN-α. Here we examined, whether other virus infections can also induce autoimmunity in Siglec-H-deficient mice. To this end we infected Siglec-H-deficient mice with influenza virus or with Lymphocytic Choriomeningitis virus (LCMV) clone 13. With both types of viruses we did not observe induction of autoimmune disease in Siglec-H-deficient mice. This can be explained by the fact that both types of viruses are ssRNA viruses that engage TLR7, rather than TLR9. Also, Influenza causes an acute infection that is rapidly cleared and the chronicity of LCMV clone 13 may not be sufficient and may rather suppress pDC functions. Siglec-H inhibited exclusively TLR-9 driven type I interferon responses, but did not affect type II or type III interferon production by pDCs. Siglec-H-deficient pDCs showed impaired Hck expression, which is a Src-family kinase expressed in myeloid cells, and downmodulation of the chemokine receptor CCR9, that has important functions for pDCs. Accordingly, Siglec-H-deficient pDCs showed impaired migration towards the CCR9 ligand CCL25. Furthermore, autoimmune-related genes such as Klk1 and DNase1l3 are downregulated in Siglec-H-deficient pDCs as well. From these findings we conclude that Siglec-H controls TLR-9-dependent, but not TLR-7 dependent inflammatory responses after virus infections and regulates chemokine responsiveness of pDCs.
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Affiliation(s)
- Nadine Szumilas
- Division of Genetics, Department of Biology, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Odilia B J Corneth
- Department of Pulmonary Medicine, Erasmus MC, University Medical Center, Rotterdam, Netherlands
| | - Christian H K Lehmann
- Laboratory of Dendritic Cell Biology, Department of Dermatology, University Hospital Erlangen, Erlangen, Germany.,Deutsches Zentrum Immuntherapie (DZI), University Hospital Erlangen, University of Erlangen-Nürnberg, Erlangen, Germany.,Medical Immunology Campus Erlangen (MICE), University of Erlangen-Nürnberg, Erlangen, Germany
| | - Heike Schmitt
- First Department of Medicine, University Hospital Erlangen, Erlangen, Germany
| | - Svenia Cunz
- Division of Genetics, Department of Biology, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Jolie G Cullen
- Division of Animal Physiology and Immunology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Talyn Chu
- Division of Animal Physiology and Immunology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Anita Marosan
- Department of Immune Modulation, University Hospital Erlangen, Erlangen, Germany
| | - Attila Mócsai
- Semmelweis University School of Medicine, Budapest, Hungary
| | - Vladimir Benes
- Genomics Core Facility, EMBL Heidelberg, Heidelberg, Germany
| | - Dietmar Zehn
- Division of Animal Physiology and Immunology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Diana Dudziak
- Laboratory of Dendritic Cell Biology, Department of Dermatology, University Hospital Erlangen, Erlangen, Germany.,Deutsches Zentrum Immuntherapie (DZI), University Hospital Erlangen, University of Erlangen-Nürnberg, Erlangen, Germany.,Medical Immunology Campus Erlangen (MICE), University of Erlangen-Nürnberg, Erlangen, Germany
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC, University Medical Center, Rotterdam, Netherlands
| | - Lars Nitschke
- Division of Genetics, Department of Biology, University of Erlangen-Nürnberg, Erlangen, Germany.,Medical Immunology Campus Erlangen (MICE), University of Erlangen-Nürnberg, Erlangen, Germany
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19
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Elsner RA, Shlomchik MJ. Germinal Center and Extrafollicular B Cell Responses in Vaccination, Immunity, and Autoimmunity. Immunity 2021; 53:1136-1150. [PMID: 33326765 DOI: 10.1016/j.immuni.2020.11.006] [Citation(s) in RCA: 303] [Impact Index Per Article: 75.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 10/19/2020] [Accepted: 11/11/2020] [Indexed: 02/07/2023]
Abstract
Activated B cells participate in either extrafollicular (EF) or germinal center (GC) responses. Canonical responses are composed of a short wave of plasmablasts (PBs) arising from EF sites, followed by GC producing somatically mutated memory B cells (MBC) and long-lived plasma cells. However, somatic hypermutation (SHM) and affinity maturation can take place at both sites, and a substantial fraction of MBC are produced prior to GC formation. Infection responses range from GC responses that persist for months to persistent EF responses with dominant suppression of GCs. Here, we review the current understanding of the functional output of EF and GC responses and the molecular switches promoting them. We discuss the signals that regulate the magnitude and duration of these responses, and outline gaps in knowledge and important areas of inquiry. Understanding such molecular switches will be critical for vaccine development, interpretation of vaccine efficacy and the treatment for autoimmune diseases.
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Affiliation(s)
- Rebecca A Elsner
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15216, USA
| | - Mark J Shlomchik
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15216, USA.
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20
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Künzli M, Reuther P, Pinschewer DD, King CG. Opposing effects of T cell receptor signal strength on CD4 T cells responding to acute versus chronic viral infection. eLife 2021; 10:61869. [PMID: 33684030 PMCID: PMC7943189 DOI: 10.7554/elife.61869] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 02/22/2021] [Indexed: 12/14/2022] Open
Abstract
A hallmark of adaptive immunity is CD4 T cells’ ability to differentiate into specialized effectors. A long-standing question is whether T cell receptor (TCR) signal strength can dominantly instruct the development of Th1 and T follicular helper (Tfh) cells across distinct infectious contexts. We characterized the differentiation of murine CD4 TCR transgenic T cells responding to altered peptide ligand lymphocytic choriomeningitis viruses (LCMV) derived from acute and chronic parental strains. We found that TCR signal strength exerts opposite and hierarchical effects on the balance of Th1 and Tfh cells responding to acute versus persistent infection. TCR signal strength correlates positively with Th1 generation during acute but negatively during chronic infection. Weakly activated T cells express lower levels of markers associated with chronic T cell stimulation and may resist functional inactivation. We anticipate that the panel of recombinant viruses described herein will be valuable for investigating a wide range of CD4 T cell responses.
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Affiliation(s)
- Marco Künzli
- Immune Cell Biology Laboratory, Department of Biomedicine, University of Basel, University Hospital Basel, Basel, Switzerland
| | - Peter Reuther
- Division of Experimental Virology, Department of Biomedicine - Haus Petersplatz, University of Basel, Basel, Switzerland
| | - Daniel D Pinschewer
- Division of Experimental Virology, Department of Biomedicine - Haus Petersplatz, University of Basel, Basel, Switzerland
| | - Carolyn G King
- Immune Cell Biology Laboratory, Department of Biomedicine, University of Basel, University Hospital Basel, Basel, Switzerland
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21
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Fox LE, Locke MC, Lenschow DJ. Context Is Key: Delineating the Unique Functions of IFNα and IFNβ in Disease. Front Immunol 2020; 11:606874. [PMID: 33408718 PMCID: PMC7779635 DOI: 10.3389/fimmu.2020.606874] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 11/11/2020] [Indexed: 12/15/2022] Open
Abstract
Type I interferons (IFNs) are critical effector cytokines of the immune system and were originally known for their important role in protecting against viral infections; however, they have more recently been shown to play protective or detrimental roles in many disease states. Type I IFNs consist of IFNα, IFNβ, IFNϵ, IFNκ, IFNω, and a few others, and they all signal through a shared receptor to exert a wide range of biological activities, including antiviral, antiproliferative, proapoptotic, and immunomodulatory effects. Though the individual type I IFN subtypes possess overlapping functions, there is growing appreciation that they also have unique properties. In this review, we summarize some of the mechanisms underlying differential expression of and signaling by type I IFNs, and we discuss examples of differential functions of IFNα and IFNβ in models of infectious disease, cancer, and autoimmunity.
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Affiliation(s)
- Lindsey E. Fox
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, United States
| | - Marissa C. Locke
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, United States
| | - Deborah J. Lenschow
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, United States
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
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22
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Kim YJ, Cubitt B, Cai Y, Kuhn JH, Vitt D, Kohlhof H, de la Torre JC. Novel Dihydroorotate Dehydrogenase Inhibitors with Potent Interferon-Independent Antiviral Activity against Mammarenaviruses In Vitro. Viruses 2020; 12:v12080821. [PMID: 32751087 PMCID: PMC7472048 DOI: 10.3390/v12080821] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 12/22/2022] Open
Abstract
Mammarenaviruses cause chronic infections in rodents, which are their predominant natural hosts. Human infection with some of these viruses causes high-consequence disease, posing significant issues in public health. Currently, no FDA-licensed mammarenavirus vaccines are available, and anti-mammarenavirus drugs are limited to an off-label use of ribavirin, which is only partially efficacious and associated with severe side effects. Dihydroorotate dehydrogenase (DHODH) inhibitors, which block de novo pyrimidine biosynthesis, have antiviral activity against viruses from different families, including Arenaviridae, the taxonomic home of mammarenaviruses. Here, we evaluate five novel DHODH inhibitors for their antiviral activity against mammarenaviruses. All tested DHODH inhibitors were potently active against lymphocytic choriomeningitis virus (LCMV) (half-maximal effective concentrations [EC50] in the low nanomolar range, selectivity index [SI] > 1000). The tested DHODH inhibitors did not affect virion cell entry or budding, but rather interfered with viral RNA synthesis. This interference resulted in a potent interferon-independent inhibition of mammarenavirus multiplication in vitro, including the highly virulent Lassa and Junín viruses.
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Affiliation(s)
- Yu-Jin Kim
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; (Y.-J.K.); (B.C.)
| | - Beatrice Cubitt
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; (Y.-J.K.); (B.C.)
| | - Yingyun Cai
- Integrated Research Facility at Fort Detrick (IRF-Frederick), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), B-8200 Research Plaza, Fort Detrick, MD 21702, USA; (Y.C.); (J.H.K.)
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick (IRF-Frederick), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), B-8200 Research Plaza, Fort Detrick, MD 21702, USA; (Y.C.); (J.H.K.)
| | - Daniel Vitt
- Immunic Therapeutics, New York City, NY 10036, USA; (D.V.); (H.K.)
| | - Hella Kohlhof
- Immunic Therapeutics, New York City, NY 10036, USA; (D.V.); (H.K.)
| | - Juan C. de la Torre
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; (Y.-J.K.); (B.C.)
- Correspondence:
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23
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Zhu JJ, Stenfeldt C, Bishop EA, Canter JA, Eschbaumer M, Rodriguez LL, Arzt J. Mechanisms of Maintenance of Foot-and-Mouth Disease Virus Persistence Inferred From Genes Differentially Expressed in Nasopharyngeal Epithelia of Virus Carriers and Non-carriers. Front Vet Sci 2020; 7:340. [PMID: 32637426 PMCID: PMC7318773 DOI: 10.3389/fvets.2020.00340] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 05/15/2020] [Indexed: 12/13/2022] Open
Abstract
Foot-and-mouth disease virus (FMDV) causes persistent infection of nasopharyngeal epithelial cells in ~50% of infected ruminants. The mechanisms involved are not clear. This study provides a continued investigation of differentially expressed genes (DEG) identified in a previously published transcriptomic study analyzing micro-dissected epithelial samples from FMDV carriers and non-carriers. Pathway analysis of DEG indicated that immune cell trafficking, cell death and hematological system could be affected by the differential gene expression. Further examination of the DEG identified five downregulated (chemerin, CCL23, CXCL15, CXCL16, and CXCL17) and one upregulated (CCL2) chemokines in carriers compared to non-carriers. The differential expression could reduce the recruitment of neutrophils, antigen-experienced T cells and dendritic cells and increase the migration of macrophages and NK cells to the epithelia in carriers, which was supported by DEG expressed in these immune cells. Downregulated chemokine expression could be mainly due to the inhibition of canonical NFκB signaling based on DEG in the signaling pathways and transcription factor binding sites predicted from the proximal promoters. Additionally, upregulated CD69, IL33, and NID1 and downregulated CASP3, IL17RA, NCR3LG1, TP53BP1, TRAF3, and TRAF6 in carriers could inhibit the Th17 response, NK cell cytotoxicity and apoptosis. Based on our findings, we hypothesize that (1) under-expression of chemokines that recruit neutrophils, antigen-experienced T cells and dendritic cells, (2) blocking NK cell binding to target cells and (3) suppression of apoptosis induced by death receptor signaling, viral RNA, and cell-mediated cytotoxicity in the epithelia compromised virus clearance and allowed FMDV to persist. These hypothesized mechanisms provide novel information for further investigation of persistent FMDV infection.
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Affiliation(s)
- James J Zhu
- USDA-ARS, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY, United States
| | - Carolina Stenfeldt
- USDA-ARS, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY, United States.,Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, United States
| | - Elizabeth A Bishop
- USDA-ARS, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY, United States
| | - Jessica A Canter
- USDA-ARS, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY, United States.,Plum Island Animal Disease Center, Oak Ridge Institute for Science and Education (ORISE), Orient, NY, United States
| | - Michael Eschbaumer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Luis L Rodriguez
- USDA-ARS, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY, United States
| | - Jonathan Arzt
- USDA-ARS, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY, United States
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24
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Abstract
Lassa fever was first described as a clinical entity fifty years ago. The causative agent Lassa virus was isolated from these first known cases. This chapter reviews the key publications on Lassa fever research that appeared in the scientific literature at that time and over the ensuing decades.
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Affiliation(s)
- Robert F Garry
- Department of Microbiology and Immunology, Tulane University School of Medicine, 1430 Tulane Avenue, New Orleans, LA, 70118, USA. .,Zalgen Labs, LLC, 20271 Goldenrod Lane, Suite 2083, Germantown, MD, 20876, USA.
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25
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Population structure of Lassa Mammarenavirus in West Africa. Viruses 2020; 12:v12040437. [PMID: 32294960 PMCID: PMC7232344 DOI: 10.3390/v12040437] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/07/2020] [Accepted: 04/10/2020] [Indexed: 01/01/2023] Open
Abstract
Lassa mammarenavirus (LASV) is the etiologic agent of Lassa fever. In endemic regions in West Africa, LASV genetic diversity tends to cluster by geographic area. Seven LASV lineages are recognized, but the role of viral genetic determinants on disease presentation in humans is uncertain. We investigated the geographic structure and distribution of LASV in West Africa. We found strong spatial clustering of LASV populations, with two major east–west and north–south diversity gradients. Analysis of ancestry components indicated that known LASV lineages diverged from an ancestral population that most likely circulated in Nigeria, although alternative locations, such as Togo, cannot be excluded. Extant sequences carrying the largest contribution of this ancestral population include the prototype Pinneo strain, the Togo isolates, and a few viruses isolated in Nigeria. The LASV populations that experienced the strongest drift circulate in Mali and the Ivory Coast. By focusing on sequences form a single LASV sublineage (IIg), we identified an ancestry component possibly associated with protection from a fatal disease outcome. Although the same ancestry component tends to associate with lower viral loads in plasma, the small sample size requires that these results are treated with extreme caution.
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26
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Freije CA, Myhrvold C, Boehm CK, Lin AE, Welch NL, Carter A, Metsky HC, Luo CY, Abudayyeh OO, Gootenberg JS, Yozwiak NL, Zhang F, Sabeti PC. Programmable Inhibition and Detection of RNA Viruses Using Cas13. Mol Cell 2019; 76:826-837.e11. [PMID: 31607545 PMCID: PMC7422627 DOI: 10.1016/j.molcel.2019.09.013] [Citation(s) in RCA: 259] [Impact Index Per Article: 43.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/18/2019] [Accepted: 09/06/2019] [Indexed: 12/23/2022]
Abstract
The CRISPR effector Cas13 could be an effective antiviral for single-stranded RNA (ssRNA) viruses because it programmably cleaves RNAs complementary to its CRISPR RNA (crRNA). Here, we computationally identify thousands of potential Cas13 crRNA target sites in hundreds of ssRNA viral species that can potentially infect humans. We experimentally demonstrate Cas13's potent activity against three distinct ssRNA viruses: lymphocytic choriomeningitis virus (LCMV); influenza A virus (IAV); and vesicular stomatitis virus (VSV). Combining this antiviral activity with Cas13-based diagnostics, we develop Cas13-assisted restriction of viral expression and readout (CARVER), an end-to-end platform that uses Cas13 to detect and destroy viral RNA. We further screen hundreds of crRNAs along the LCMV genome to evaluate how conservation and target RNA nucleotide content influence Cas13's antiviral activity. Our results demonstrate that Cas13 can be harnessed to target a wide range of ssRNA viruses and CARVER's potential broad utility for rapid diagnostic and antiviral drug development.
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Affiliation(s)
- Catherine A Freije
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; PhD Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA.
| | - Cameron Myhrvold
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.
| | - Chloe K Boehm
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - Aaron E Lin
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; PhD Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA
| | - Nicole L Welch
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; PhD Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA
| | - Amber Carter
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - Hayden C Metsky
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02142, USA
| | - Cynthia Y Luo
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Omar O Abudayyeh
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Science, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Health Sciences and Technology, MIT, Cambridge, MA 02139, USA
| | - Jonathan S Gootenberg
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Science, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Nathan L Yozwiak
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Feng Zhang
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Science, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Howard Hughes Medical Institute (HHMI), Chevy Chase, MD 20815, USA
| | - Pardis C Sabeti
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; PhD Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; Howard Hughes Medical Institute (HHMI), Chevy Chase, MD 20815, USA; Department of Immunology and Infectious Disease, T.H. Chan Harvard School of Public Health, Boston, MA 02115, USA.
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27
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A unique variant of lymphocytic choriomeningitis virus that induces pheromone binding protein MUP: Critical role for CTL. Proc Natl Acad Sci U S A 2019; 116:18001-18008. [PMID: 31427525 DOI: 10.1073/pnas.1907070116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lymphocytic choriomeningitis virus (LCMV) WE variant 2.2 (v2.2) generated a high level of the major mouse urinary protein: MUP. Mice infected with LCMV WE v54, which differed from v2.2 by a single amino acid in the viral glycoprotein, failed to generate MUP above baseline levels found in uninfected controls. Variant 54 bound at 2.5 logs higher affinity to the LCMV receptor α-dystroglycan (α-DG) than v2.2 and entered α-DG-expressing but not α-DG-null cells. Variant 2.2 infected both α-DG-null or -expressing cells. Variant 54 infected more dendritic cells, generated a negligible CD8 T cell response, and caused a persistent infection, while v2.2 generated cytotoxic T lymphocytes (CTLs) and cleared virus within 10 days. By 20 days postinfection and through the 80-day observation period, significantly higher amounts of MUP were found in v2.2-infected mice. Production of MUP was dependent on virus-specific CTL as deletion of such cells aborted MUP production. Furthermore, MUP production was not elevated in v2.2 persistently infected mice unless virus was cleared following transfer of virus-specific CTL.
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28
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Differential Antibody-Based Immune Response against Isolated GP1 Receptor-Binding Domains from Lassa and Junín Viruses. J Virol 2019; 93:JVI.00090-19. [PMID: 30728269 DOI: 10.1128/jvi.00090-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 01/30/2019] [Indexed: 01/10/2023] Open
Abstract
There are two predominant subgroups in the Arenaviridae family of viruses, the Old World and the New World viruses, that use distinct cellular receptors for entry. While New World viruses typically elicit good neutralizing antibody responses, the Old World viruses generally evade such responses. Antibody-based immune responses are directed against the glycoprotein spike complexes that decorate the viruses. A thick coat of glycans reduces the accessibility of antibodies to the surface of spike complexes from Old World viruses, but other mechanisms may further hamper the development of efficient humoral responses. Specifically, it was suggested that the GP1 receptor-binding module of the Old World Lassa virus might help with evasion of the humoral response. Here we investigated the immunogenicity of the GP1 domain from Lassa virus and compared it to that of the GP1 domain from the New World Junín virus. We found striking differences in the ability of antibodies that were developed against these immunogens to target the same GP1 receptor-binding domains in the context of the native spike complexes. Whereas GP1 from Junín virus elicited productive neutralizing responses, GP1 from Lassa virus elicited only nonproductive responses. These differences can be rationalized by the conformational changes that GP1 from Lassa virus but not GP1 from Junín virus undergoes after dissociating from the trimeric spike complex. Hence, shedding of GP1 in the case of Lassa virus can indeed serve as a mechanism to subvert the humoral immune response. Moreover, the realization that a recombinant protein may be used to elicit a productive response against the New World Junín virus may suggest a novel and safe way to design future vaccines.IMPORTANCE Some viruses that belong to the Arenaviridae family, like Lassa and Junín viruses, are notorious human pathogens, which may lead to fatal outcomes when they infect people. It is thus important to develop means to combat these viruses. For developing effective vaccines, it is vital to understand the basic mechanisms that these viruses utilize in order to evade or overcome host immune responses. It was previously noted that the GP1 receptor-binding domain from Lassa virus is shed and accumulates in the serum of infected individuals. This raised the possibility that Lassa virus GP1 may function as an immunological decoy. Here we demonstrate that mice develop nonproductive immune responses against GP1 from Lassa virus, which is in contrast to the effective neutralizing responses that GP1 from Junín virus elicits. Thus, GP1 from Lassa virus is indeed an immunological decoy and GP1 from Junín virus may serve as a constituent of a future vaccine.
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Kahan SM, Zajac AJ. Immune Exhaustion: Past Lessons and New Insights from Lymphocytic Choriomeningitis Virus. Viruses 2019; 11:E156. [PMID: 30781904 PMCID: PMC6410286 DOI: 10.3390/v11020156] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 02/08/2019] [Accepted: 02/09/2019] [Indexed: 12/16/2022] Open
Abstract
Lymphocytic choriomeningitis virus (LCMV) is a paradigm-forming experimental system with a remarkable track record of contributing to the discovery of many of the fundamental concepts of modern immunology. The ability of LCMV to establish a chronic infection in immunocompetent adult mice was instrumental for identifying T cell exhaustion and this system has been invaluable for uncovering the complexity, regulators, and consequences of this state. These findings have been directly relevant for understanding why ineffective T cell responses commonly arise during many chronic infections including HIV and HCV, as well as during tumor outgrowth. The principal feature of exhausted T cells is the inability to elaborate the array of effector functions necessary to contain the underlying infection or tumor. Using LCMV to determine how to prevent and reverse T cell exhaustion has highlighted the potential of checkpoint blockade therapies, most notably PD-1 inhibition strategies, for improving cellular immunity under conditions of antigen persistence. Here, we discuss the discovery, properties, and regulators of exhausted T cells and highlight how LCMV has been at the forefront of advancing our understanding of these ineffective responses.
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Affiliation(s)
- Shannon M Kahan
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | - Allan J Zajac
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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Pontremoli C, Forni D, Sironi M. Arenavirus genomics: novel insights into viral diversity, origin, and evolution. Curr Opin Virol 2019; 34:18-28. [DOI: 10.1016/j.coviro.2018.11.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 11/01/2018] [Accepted: 11/02/2018] [Indexed: 12/18/2022]
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Abdel-Hakeem MS. Viruses Teaching Immunology: Role of LCMV Model and Human Viral Infections in Immunological Discoveries. Viruses 2019; 11:E106. [PMID: 30691215 PMCID: PMC6410308 DOI: 10.3390/v11020106] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 01/24/2019] [Accepted: 01/25/2019] [Indexed: 12/16/2022] Open
Abstract
Virology has played an essential role in deciphering many immunological phenomena, thus shaping our current understanding of the immune system. Animal models of viral infection and human viral infections were both important tools for immunological discoveries. This review discusses two immunological breakthroughs originally identified with the help of the lymphocytic choriomeningitis virus (LCMV) model; immunological restriction by major histocompatibility complex and immunotherapy using checkpoint blockade. In addition, we discuss related discoveries such as development of tetramers, viral escape mutation, and the phenomenon of T-cell exhaustion.
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Affiliation(s)
- Mohamed S Abdel-Hakeem
- Penn Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Kasr El-Aini, Cairo 11562, Egypt.
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Cohen-Dvashi H, Kilimnik I, Diskin R. Structural basis for receptor recognition by Lujo virus. Nat Microbiol 2018; 3:1153-1160. [PMID: 30150732 DOI: 10.1038/s41564-018-0224-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 07/24/2018] [Indexed: 12/31/2022]
Abstract
Lujo virus (LUJV) has emerged as a highly fatal human pathogen. Despite its membership among the Arenaviridae, LUJV does not classify with the known Old and New World groups of that viral family. Likewise, LUJV was recently found to use neuropilin-2 (NRP2) as a cellular receptor instead of the canonical receptors used by Old World and New World arenaviruses. The emergence of a deadly pathogen into human populations using an unprecedented entry route raises many questions regarding the mechanism of cell recognition. To provide the basis for combating LUJV in particular, and to increase our general understanding of the molecular changes that accompany an evolutionary switch to a new receptor for arenaviruses, we used X-ray crystallography to reveal how the GP1 receptor-binding domain of LUJV (LUJVGP1) recognizes NRP2. Structural data show that LUJVGP1 is more similar to Old World than to New World arenaviruses. Structural analysis supported by experimental validation further suggests that NRP2 recognition is metal-ion dependent and that the complete NRP2 binding site is formed in the context of the trimeric spike. Taken together, our data provide the mechanism for the cell attachment step of LUJV and present indispensable information for combating this phatogen.
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Affiliation(s)
- Hadas Cohen-Dvashi
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Itay Kilimnik
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Ron Diskin
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
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Lymphocytic choriomeningitis virus Clone 13 infection causes either persistence or acute death dependent on IFN-1, cytotoxic T lymphocytes (CTLs), and host genetics. Proc Natl Acad Sci U S A 2018; 115:E7814-E7823. [PMID: 30061383 DOI: 10.1073/pnas.1804674115] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Understanding of T cell exhaustion and successful therapy to restore T cell function was first described using Clone (Cl) 13 variant selected from the lymphocytic choriomeningitis virus (LCMV) Armstrong (ARM) 53b parental strain. T cell exhaustion plays a pivotal role in both persistent infections and cancers of mice and humans. C57BL/6, BALB, SWR/J, A/J, 129, C3H, and all but one collaborative cross (CC) mouse strain following Cl 13 infection have immunosuppressed T cell responses, high PD-1, and viral titers leading to persistent infection and normal life spans. In contrast, the profile of FVB/N, NZB, PL/J, SL/J, and CC NZO mice challenged with Cl 13 is a robust T cell response, high titers of virus, PD-1, and Lag3 markers on T cells. These mice all die 7 to 9 d after Cl 13 infection. Death is due to enhanced pulmonary endothelial vascular permeability, pulmonary edema, collapse of alveolar air spaces, and respiratory failure. Pathogenesis involves abundant levels of Cl 13 receptor alpha-dystroglycan on endothelial cells, with high viral replication in such cells leading to immunopathologic injury. Death is aborted by blockade of interferon-1 (IFN-1) signaling or deletion of CD8 T cells.
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Nice TJ, Robinson BA, Van Winkle JA. The Role of Interferon in Persistent Viral Infection: Insights from Murine Norovirus. Trends Microbiol 2018; 26:510-524. [PMID: 29157967 PMCID: PMC5957778 DOI: 10.1016/j.tim.2017.10.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 10/20/2017] [Accepted: 10/30/2017] [Indexed: 12/21/2022]
Abstract
Persistent viral infections result from evasion or avoidance of sterilizing immunity, extend the timeframe of virus transmission, and can trigger disease. Prior studies in mouse models of persistent infection have suggested that ineffective adaptive immune responses are necessary for persistent viral infection. However, recent work in the murine norovirus (MNV) model of persistent infection demonstrates that innate immunity can control both early and persistent viral replication independently of adaptive immune effector functions. Interferons (IFNs) are central to the innate control of persistent MNV, apart from a role in modulating adaptive immunity. Furthermore, subtypes of IFN play distinct tissue-specific roles in innate control of persistent MNV infection. Type I IFN (IFN-α/β) controls systemic replication, and type III IFN (IFN-λ) controls MNV persistence in the intestinal epithelium. In this article, we review recent findings in the MNV model, highlighting the role of IFNs and innate immunity in clearing persistent viral infection, and discussing the broader implications of these findings for control of persistent human infections.
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Affiliation(s)
- Timothy J Nice
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, USA.
| | - Bridget A Robinson
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, USA
| | - Jacob A Van Winkle
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, USA
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Hastie KM, Saphire EO. Lassa virus glycoprotein: stopping a moving target. Curr Opin Virol 2018; 31:52-58. [PMID: 29843991 PMCID: PMC6193841 DOI: 10.1016/j.coviro.2018.05.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 05/10/2018] [Accepted: 05/11/2018] [Indexed: 11/25/2022]
Abstract
The structure of a prefusion arenavirus GPC was enigmatic for many years, owing to the metastable and non-covalent nature of the association between the receptor binding and fusion subunits. Recent engineering efforts to stabilize the glycoprotein of the Old World arenavirus Lassa in a native, yet cleaved state, allowed the first structure of any arenavirus prefusion GPC trimer to be determined. Comparison of this structure with the structures of other arenavirus glycoprotein subunits reveals surprising findings: that the receptor binding subunit, GP1, of Lassa virus is conformationally labile, while the GP1 subunit of New World arenaviruses is not, and that the arenavirus GPC adopts a trimeric state unlike other glycoproteins with similar fusion machinery. Structural analysis, combined with recent biochemical data regarding antibody epitopes and receptor binding requirements, provides a basis for rational vaccine design.
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Affiliation(s)
- Kathryn M Hastie
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Erica Ollmann Saphire
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA; Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA.
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Khamina K, Lercher A, Caldera M, Schliehe C, Vilagos B, Sahin M, Kosack L, Bhattacharya A, Májek P, Stukalov A, Sacco R, James LC, Pinschewer DD, Bennett KL, Menche J, Bergthaler A. Characterization of host proteins interacting with the lymphocytic choriomeningitis virus L protein. PLoS Pathog 2017; 13:e1006758. [PMID: 29261807 PMCID: PMC5738113 DOI: 10.1371/journal.ppat.1006758] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 11/17/2017] [Indexed: 01/10/2023] Open
Abstract
RNA-dependent RNA polymerases (RdRps) play a key role in the life cycle of RNA viruses and impact their immunobiology. The arenavirus lymphocytic choriomeningitis virus (LCMV) strain Clone 13 provides a benchmark model for studying chronic infection. A major genetic determinant for its ability to persist maps to a single amino acid exchange in the viral L protein, which exhibits RdRp activity, yet its functional consequences remain elusive. To unravel the L protein interactions with the host proteome, we engineered infectious L protein-tagged LCMV virions by reverse genetics. A subsequent mass-spectrometric analysis of L protein pulldowns from infected human cells revealed a comprehensive network of interacting host proteins. The obtained LCMV L protein interactome was bioinformatically integrated with known host protein interactors of RdRps from other RNA viruses, emphasizing interconnected modules of human proteins. Functional characterization of selected interactors highlighted proviral (DDX3X) as well as antiviral (NKRF, TRIM21) host factors. To corroborate these findings, we infected Trim21-/- mice with LCMV and found impaired virus control in chronic infection. These results provide insights into the complex interactions of the arenavirus LCMV and other viral RdRps with the host proteome and contribute to a better molecular understanding of how chronic viruses interact with their host. RNA-dependent RNA-polymerases (RdRps) play a key role in the life cycle of RNA viruses. They interact with cellular proteins during replication and transcription processes and impact the immunobiology of viral infections. This study characterized the host protein interactome of the RdRp-containing L protein of the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV). Several L protein interactors with proviral and antiviral effects were identified in vitro, and mice lacking the identified L protein interactor TRIM21 exhibited impaired control of chronic LCMV infection. Integration of the L protein interactomes with known RdRp interactomes from other RNA viruses highlighted common and virus-specific strategies to interact with the host proteome, which may indicate novel avenues for antiviral interventions.
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Affiliation(s)
- Kseniya Khamina
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Alexander Lercher
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Michael Caldera
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Christopher Schliehe
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Bojan Vilagos
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Mehmet Sahin
- University of Basel, Department of Biomedicine–Haus Petersplatz, Division of Experimental Virology, Basel, Switzerland
| | - Lindsay Kosack
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Anannya Bhattacharya
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Peter Májek
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Alexey Stukalov
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Roberto Sacco
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Leo C. James
- Division of Protein and Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Daniel D. Pinschewer
- University of Basel, Department of Biomedicine–Haus Petersplatz, Division of Experimental Virology, Basel, Switzerland
| | - Keiryn L. Bennett
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Jörg Menche
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
| | - Andreas Bergthaler
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse, Vienna, Austria
- * E-mail:
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Acciani M, Alston JT, Zhao G, Reynolds H, Ali AM, Xu B, Brindley MA. Mutational Analysis of Lassa Virus Glycoprotein Highlights Regions Required for Alpha-Dystroglycan Utilization. J Virol 2017; 91:e00574-17. [PMID: 28679759 PMCID: PMC5571257 DOI: 10.1128/jvi.00574-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 06/22/2017] [Indexed: 12/27/2022] Open
Abstract
Lassa virus (LASV) is an enveloped RNA virus endemic to West Africa and responsible for severe cases of hemorrhagic fever. Virus entry is mediated by the glycoprotein complex consisting of a stable-signal peptide, a receptor-binding subunit, GP1, and a viral-host membrane fusion subunit, GP2. Several cellular receptors can interact with the GP1 subunit and mediate viral entry, including alpha-dystroglycan (αDG) and lysosome-associated membrane protein 1 (LAMP1). In order to define the regions within GP1 that interact with the cellular receptors, we implemented insertional mutagenesis, carbohydrate shielding, and alanine scanning mutagenesis. Eighty GP constructs were engineered and evaluated for GP1-GP2 processing, surface expression, and the ability to mediate cell-to-cell fusion after low-pH exposure. To examine virus-to-cell entry, 49 constructs were incorporated onto vesicular stomatitis virus (VSV) pseudoparticles and transduction efficiencies were monitored in HAP1 and HAP1-ΔDAG1 cells that differentially produce the αDG cell surface receptor. Seven constructs retained efficient transduction in HAP1-ΔDAG1 cells yet poorly transduced HAP1 cells, suggesting that they are involved in αDG utilization. Residues H141, N146, F147, and Y150 cluster at the predicted central core of the trimeric interface and are important for GP-αDG interaction. Additionally, H92A-H93A, 150HA, 172HA, and 230HA displayed reduced transduction in both HAP1 and HAP1-ΔDAG1 cells, despite efficient cell-to-cell fusion activity. These mutations may interfere with interactions with the endosomal receptor LAMP1 or interfere at another stage in entry that is common to both cell lines. Insight gained from these data can aid in the development of more-effective entry inhibitors by blocking receptor interactions.IMPORTANCE Countries in which Lassa virus is endemic, such as Nigeria, Sierra Leone, Guinea, and Liberia, usually experience a seasonal outbreak of the virus from December to March. Currently, there is neither a preventative vaccine nor a therapeutic available to effectively treat severe Lassa fever. One way to thwart virus infection is to inhibit interaction with cellular receptors. It is known that the GP1 subunit of the Lassa glycoprotein complex plays a critical role in receptor recognition. Our results highlight a region within the Lassa virus GP1 protein that interacts with the cellular receptor alpha-dystroglycan. This information may be used for future development of new Lassa virus antivirals.
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Affiliation(s)
- Marissa Acciani
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Jacob T Alston
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Guohui Zhao
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Hayley Reynolds
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Afroze M Ali
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Brian Xu
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Melinda A Brindley
- Department of Infectious Diseases, Department of Population Health, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
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Pontremoli C, Forni D, Cagliani R, Pozzoli U, Riva S, Bravo IG, Clerici M, Sironi M. Evolutionary analysis of Old World arenaviruses reveals a major adaptive contribution of the viral polymerase. Mol Ecol 2017; 26:5173-5188. [PMID: 28779541 DOI: 10.1111/mec.14282] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 07/25/2017] [Accepted: 07/31/2017] [Indexed: 12/17/2022]
Abstract
The Old World (OW) arenavirus complex includes several species of rodent-borne viruses, some of which (i.e., Lassa virus, LASV and Lymphocytic choriomeningitis virus, LCMV) cause human diseases. Most LCMV and LASV infections are caused by rodent-to-human transmissions. Thus, viral evolution is largely determined by events that occur in the wildlife reservoirs. We used a set of human- and rodent-derived viral sequences to investigate the evolutionary history underlying OW arenavirus speciation, as well as the more recent selective events that accompanied LASV spread in West Africa. We show that the viral RNA polymerase (L protein) was a major positive selection target in OW arenaviruses and during LASV out-of-Nigeria migration. No evidence of selection was observed for the glycoprotein, whereas positive selection acted on the nucleoprotein (NP) during LCMV speciation. Positively selected sites in L and NP are surrounded by highly conserved residues, and the bulk of the viral genome evolves under purifying selection. Several positively selected sites are likely to modulate viral replication/transcription. In both L and NP, structural features (solvent exposed surface area) are important determinants of site-wise evolutionary rate variation. By incorporating several rodent-derived sequences, we also performed an analysis of OW arenavirus codon adaptation to the human host. Results do not support a previously hypothesized role of codon adaptation in disease severity for non-Nigerian strains. In conclusion, L and NP represent the major selection targets and possible determinants of disease presentation; these results suggest that field surveys and experimental studies should primarily focus on these proteins.
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Affiliation(s)
- Chiara Pontremoli
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Diego Forni
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Rachele Cagliani
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Uberto Pozzoli
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Stefania Riva
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Ignacio G Bravo
- Laboratory MIVEGEC, UMR CNRS 5290, IRD 224, UM, Centre National de la Recherche Scientifique, Montpellier, France
| | - Mario Clerici
- Department of Physiopathology and Transplantation, University of Milan, Milan, Italy.,Don C. Gnocchi Foundation ONLUS, IRCCS, Milan, Italy
| | - Manuela Sironi
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
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Iwasaki M, Sharma SM, Marro BS, de la Torre JC. Resistance of human plasmacytoid dendritic CAL-1 cells to infection with lymphocytic choriomeningitis virus (LCMV) is caused by restricted virus cell entry, which is overcome by contact of CAL-1 cells with LCMV-infected cells. Virology 2017; 511:106-113. [PMID: 28843812 DOI: 10.1016/j.virol.2017.08.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 08/07/2017] [Accepted: 08/14/2017] [Indexed: 01/06/2023]
Abstract
Plasmacytoid dendritic cells (pDCs), a main source of type I interferon in response to viral infection, are an early cell target during lymphocytic choriomeningitis virus (LCMV) infection, which has been associated with the LCMV's ability to establish chronic infections. Human blood-derived pDCs have been reported to be refractory to ex vivo LCMV infection. In the present study we show that human pDC CAL-1 cells are refractory to infection with cell-free LCMV, but highly susceptible to infection with recombinant LCMVs carrying the surface glycoprotein of VSV, indicating that LCMV infection of CAL-1 cells is restricted at the cell entry step. Co-culture of uninfected CAL-1 cells with LCMV-infected HEK293 cells enabled LCMV to infect CAL-1 cells. This cell-to-cell spread required direct cell-cell contact and did not involve exosome pathway. Our findings indicate the presence of a novel entry pathway utilized by LCMV to infect pDC.
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Affiliation(s)
- Masaharu Iwasaki
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Siddhartha M Sharma
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Brett S Marro
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Juan C de la Torre
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA.
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Hastie KM, Zandonatti MA, Kleinfelter LM, Heinrich ML, Rowland MM, Chandran K, Branco LM, Robinson JE, Garry RF, Saphire EO. Structural basis for antibody-mediated neutralization of Lassa virus. Science 2017; 356:923-928. [PMID: 28572385 PMCID: PMC6007842 DOI: 10.1126/science.aam7260] [Citation(s) in RCA: 163] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 04/28/2017] [Indexed: 12/25/2022]
Abstract
The arenavirus Lassa causes severe hemorrhagic fever and a significant disease burden in West Africa every year. The glycoprotein, GPC, is the sole antigen expressed on the viral surface and the critical target for antibody-mediated neutralization. Here we present the crystal structure of the trimeric, prefusion ectodomain of Lassa GP bound to a neutralizing antibody from a human survivor at 3.2-angstrom resolution. The antibody extensively anchors two monomers together at the base of the trimer, and biochemical analysis suggests that it neutralizes by inhibiting conformational changes required for entry. This work illuminates pH-driven conformational changes in both receptor-binding and fusion subunits of Lassa virus, illustrates the unique assembly of the arenavirus glycoprotein spike, and provides a much-needed template for vaccine design against these threats to global health.
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Affiliation(s)
- Kathryn M Hastie
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Michelle A Zandonatti
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Lara M Kleinfelter
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | | | | | - Kartik Chandran
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | | | - James E Robinson
- Department of Pediatrics, School of Medicine, Tulane University, New Orleans, LA, USA
| | - Robert F Garry
- Zalgen Labs, Germantown, MD, USA
- Department of Microbiology and Immunology, Tulane University, New Orleans, LA, USA
| | - Erica Ollmann Saphire
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA.
- Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
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Takagi T, Ohsawa M, Yamanaka H, Matsuda N, Sato H, Ohsawa K. Difference of two new LCMV strains in lethality and viral genome load in tissues. Exp Anim 2017; 66:199-208. [PMID: 28260717 PMCID: PMC5543240 DOI: 10.1538/expanim.16-0097] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
More than 30 strains of lymphocytic choriomeningitis virus (LCMV) have been isolated from
mice, hamsters and humans in the United States, Europe and Japan. Experimentally infected
mice exhibit different clinical signs and lethality depending on a combination of LCMV
epitope peptides and host major histocompatibility complex (MHC) class I molecules. This
study examined the pathogenicity, clinical signs and lethality, of two new LCMV strains
(BRC and OQ28) using three inbred mouse strains with different genetic backgrounds having
different H-2D haplotypes. Strain OQ28 (OQ28) infected
mice exhibited clinical signs and lethality, whereas strain BRC (BRC) infected mice showed
no clinical signs of infection. The viral genome load in tissues of C57BL/6 mice infected
with two strains was determined using one-step real time RT-PCR. In C57BL/6 mice, higher
levels of OQ28 viral genome load were detected in all tissues rather than were present in
BRC infected mice. The viral genome load in lungs of both virus strains remained higher
levels than in other tissues at 28 days post infection. Comparing sequences of the three
LCMV epitope peptide regions revealed one non-conservative amino acid substitution codon
in OQ28 and two amino acid differences in BRC. These results suggest that the varied
pathogenicity and viral genome load of LCMV strains are not based only on differences in
the host MHC class I molecule.
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Affiliation(s)
- Toshikazu Takagi
- Division of Comparative Medicine, Center for Frontier Life Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523, Japan.,Quality Control Department, Bio Technical Center, Japan SLC, Inc., 3-5-1 Aoihigashi, Naka, Hamamatsu, Shizuoka 433-8114, Japan
| | - Makiko Ohsawa
- Division of Comparative Medicine, Center for Frontier Life Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523, Japan
| | - Hitoki Yamanaka
- Division of Comparative Medicine, Center for Frontier Life Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523, Japan
| | - Naoki Matsuda
- Division of Radiation Biology and Protection, Center for Frontier Life Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523, Japan
| | - Hiroshi Sato
- Division of Comparative Medicine, Center for Frontier Life Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523, Japan.,National Institute for Physiological Sciences, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan
| | - Kazutaka Ohsawa
- Division of Comparative Medicine, Center for Frontier Life Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523, Japan
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Mbanwi AN, Wang C, Geddes K, Philpott DJ, Watts TH. Irreversible splenic atrophy following chronic LCMV infection is associated with compromised immunity in mice. Eur J Immunol 2016; 47:94-106. [PMID: 27730627 DOI: 10.1002/eji.201646666] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 09/25/2016] [Accepted: 10/07/2016] [Indexed: 01/16/2023]
Abstract
Lymphocytic choriomeningitis virus clone 13 (LCMV13) infection of mice is a widely used model for investigating the mechanisms driving persistent viral infection in humans. LCMV13 disrupts splenic architecture early during infection, but this returns to normal within a few weeks. However, the long-term effects of LCMV13 infection on splenic structure have not been reported. Here, we report that persistent infection with LCMV13 results in sustained splenic atrophy that persists for at least 500 days following infection, whereas infection with the acutely infecting LCMV Armstrong is associated with a return to preinfection spleen weights. Splenic atrophy is associated with loss of T, B, and non-B non-T cells, with B cells most significantly affected. These effects were partly ameliorated by anti-NK1.1 or anti-CD8 antibody treatment. Antigen presentation was detectable at the time of contraction of the spleen, but no longer detected at late time points, suggesting that continued antigen presentation is not required to maintain splenic atrophy. Immunity to Salmonella infection and influenza vaccination were decreased after the virus was no longer detected. Thus splenic atrophy following LCMV13 infection is irreversible and may contribute to impaired immunity following clearance of LCMV13.
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Affiliation(s)
- Achire N Mbanwi
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Chao Wang
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Kaoru Geddes
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Dana J Philpott
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Tania H Watts
- Department of Immunology, University of Toronto, Toronto, ON, Canada
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43
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Residues K465 and G467 within the Cytoplasmic Domain of GP2 Play a Critical Role in the Persistence of Lymphocytic Choriomeningitis Virus in Mice. J Virol 2016; 90:10102-10112. [PMID: 27581982 DOI: 10.1128/jvi.01303-16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 08/22/2016] [Indexed: 11/20/2022] Open
Abstract
Several arenaviruses, chiefly Lassa virus (LASV), cause hemorrhagic fever disease in humans and pose serious public health concerns in their regions of endemicity. Moreover, mounting evidence indicates that the worldwide-distributed prototypic arenavirus, lymphocytic choriomeningitis virus (LCMV), is a neglected human pathogen of clinical significance. We have documented that a recombinant LCMV containing the glycoprotein (GPC) gene of LASV within the backbone of the immunosuppressive clone 13 (Cl-13) variant of the Armstrong strain of LCMV (rCl-13/LASV-GPC) exhibited Cl-13-like growth properties in cultured cells, but in contrast to Cl-13, rCl-13/LASV-GPC was unable to establish persistence in immunocompetent adult mice, which prevented its use for some in vivo experiments. Recently, V459K and K461G mutations within the GP2 cytoplasmic domain (CD) of rCl-13/LASV-GPC were shown to increase rCl-13/LASV-GPC infectivity in mice. Here, we generated rCl-13(GPC/VGKS) by introducing the corresponding revertant mutations K465V and G467K within GP2 of rCl-13 and we show that rCl-13(GPC/VGKS) was unable to persist in mice. K465V and G467K mutations did not affect GPC processing, virus RNA replication, or gene expression. In addition, rCl-13(GPC/VGKS) grew to high titers in cultured cell lines and in immunodeficient mice. Further analysis revealed that rCl-13(GPC/VGKS) infected fewer splenic plasmacytoid dendritic cells than rCl-13, yet the two viruses induced similar type I interferon responses in mice. Our findings have identified novel viral determinants of Cl-13 persistence and also revealed that virus GPC-host interactions yet to be elucidated critically contribute to Cl-13 persistence. IMPORTANCE The prototypic arenavirus, lymphocytic choriomeningitis virus (LCMV), provides investigators with a superb experimental model system to investigate virus-host interactions. The Armstrong strain (ARM) of LCMV causes an acute infection, whereas its derivative, clone 13 (Cl-13), causes a persistent infection. Mutations F260L and K1079Q within GP1 and L polymerase, respectively, have been shown to play critical roles in Cl-13's ability to persist in mice. However, there is an overall lack of knowledge about other viral determinants required for Cl-13's persistence. Here, we report that mutations K465V and G467K within the cytoplasmic domain of Cl-13 GP2 resulted in a virus, rCl-13(GPC/VGKS), that failed to persist in mice despite exhibiting Cl-13 wild-type-like fitness in cultured cells and immunocompromised mice. This finding has uncovered novel viral determinants of viral persistence, and a detailed characterization of rCl-13(GPC/VGKS) can provide novel insights into the mechanisms underlying persistent viral infection.
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44
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T cell exhaustion and immune-mediated disease-the potential for therapeutic exhaustion. Curr Opin Immunol 2016; 43:74-80. [PMID: 27744240 DOI: 10.1016/j.coi.2016.09.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 09/23/2016] [Indexed: 12/22/2022]
Abstract
T cell exhaustion represents a continuous spectrum of cellular dysfunction induced during chronic viral infection, facilitating viral persistence and associating with poor clinical outcome. Modulation of T cell exhaustion can restore function in exhausted CD8 T cells, promoting viral clearance. Exhaustion has also been implicated as playing an important role in anti-tumour responses, whereby exhausted tumour-infiltrating lymphocytes fail to control tumour progression. More recently exhaustion has been linked to long-term clinical outcome in multiple autoimmune diseases but, in contrast to cancer or infection, it is associated with a favourable clinical outcome characterised by fewer relapses. An increasing understanding of key inhibitory signals promoting exhaustion has led to advances in therapy for chronic infection and cancer. An increasing understanding of this biology may facilitate novel treatment approaches for autoimmunity through the therapeutic induction of exhaustion.
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45
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Moseman EA, Wu T, de la Torre JC, Schwartzberg PL, McGavern DB. Type I interferon suppresses virus-specific B cell responses by modulating CD8 + T cell differentiation. Sci Immunol 2016; 1:eaah3565. [PMID: 27812556 PMCID: PMC5089817 DOI: 10.1126/sciimmunol.aah3565] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2024]
Abstract
Studies have established a role for T cells in resolving persistent viral infections, yet emerging evidence indicates that both T and B cells are required to control some viruses. During persistent infection, a marked lag or failure to generate neutralizing antibodies is commonly observed and likely contributes to an inability to control certain pathogens. Using lymphocytic choriomeningitis virus (LCMV) as a model, we have examined how a persistent viral infection can suppress neutralizing humoral immunity. By tracking the fate of virus-specific B cells in vivo, we report that LCMV-specific B cells were rapidly deleted within a few days of persistent infection, and this deletion was completely reversed by blockade of type I interferon (IFN-I) signaling. Early interference with IFN-I signaling promoted survival and differentiation of LCMV-specific B cells, which accelerated the generation of neutralizing antibodies. This marked improvement in antiviral humoral immunity did not rely on the cessation of IFN-I signaling in B cells but on alterations in the virus-specific CD8+ T cell response. Using two-photon microscopy and in vivo calcium imaging, we observed that cytotoxic T lymphocytes (CTLs) productively engaged and killed LCMV-specific B cells in a perforin-dependent manner within the first few days of infection. Blockade of IFN-I signaling protected LCMV-specific B cells by promoting CTL dysfunction. Therapeutic manipulation of this pathway may facilitate efforts to promote humoral immunity during persistent viral infection in humans. Our findings illustrate how events that occur early after infection can disturb the resultant adaptive response and contribute to viral persistence.
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Affiliation(s)
- E. Ashley Moseman
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tuoqi Wu
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | | | - Pamela L. Schwartzberg
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dorian B. McGavern
- Viral Immunology and Intravital Imaging Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
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46
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Ng CT, Mendoza JL, Garcia KC, Oldstone MBA. Alpha and Beta Type 1 Interferon Signaling: Passage for Diverse Biologic Outcomes. Cell 2016; 164:349-52. [PMID: 26824652 DOI: 10.1016/j.cell.2015.12.027] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 11/03/2015] [Accepted: 12/14/2015] [Indexed: 11/18/2022]
Abstract
Type I interferon (IFN-I) elicits a complex cascade of events in response to microbial infection. Here, we review recent developments illuminating the large number of IFN-I species and describing their unique biologic functions.
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Affiliation(s)
- Cherie T Ng
- Department of Immunology & Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Juan L Mendoza
- Department of Molecular & Cellular Physiology and Department of Structural Biology, Howard Hughes Medical Institute, Stanford University School of Medicine, 279 Campus Drive, Stanford, CA 94305, USA
| | - K Christopher Garcia
- Department of Molecular & Cellular Physiology and Department of Structural Biology, Howard Hughes Medical Institute, Stanford University School of Medicine, 279 Campus Drive, Stanford, CA 94305, USA
| | - Michael B A Oldstone
- Department of Immunology & Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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47
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Crystal structure of the prefusion surface glycoprotein of the prototypic arenavirus LCMV. Nat Struct Mol Biol 2016; 23:513-521. [PMID: 27111888 PMCID: PMC4945123 DOI: 10.1038/nsmb.3210] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 03/24/2016] [Indexed: 11/08/2022]
Abstract
Arenaviruses exist worldwide and can cause hemorrhagic fever and neurologic disease. A single glycoprotein expressed on the viral surface mediates entry into target cells. This glycoprotein, termed GPC, contains a membrane-associated signal peptide, a receptor-binding subunit termed GP1 and a fusion-mediating subunit termed GP2. Although GPC is a critical target of antibodies and vaccines, the structure of the metastable GP1-GP2 prefusion complex has remained elusive for all arenaviruses. Here we describe the crystal structure of the fully glycosylated prefusion GP1-GP2 complex of the prototypic arenavirus LCMV at 3.5 Å. This structure reveals the conformational changes that the arenavirus glycoprotein must undergo to cause fusion and illustrates the fusion regions and potential oligomeric states.
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48
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Oldstone MBA. The Anatomy of a Career in Science. DNA Cell Biol 2016; 35:109-17. [PMID: 26836569 DOI: 10.1089/dna.2016.3232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Michael B A Oldstone
- Viral-Immunobiology Laboratory, The Scripps Research Institute , La Jolla, California
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49
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Ng CT, Sullivan BM, Teijaro JR, Lee AM, Welch M, Rice S, Sheehan KCF, Schreiber RD, Oldstone MBA. Blockade of interferon Beta, but not interferon alpha, signaling controls persistent viral infection. Cell Host Microbe 2016; 17:653-61. [PMID: 25974304 DOI: 10.1016/j.chom.2015.04.005] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 02/09/2015] [Accepted: 03/19/2015] [Indexed: 12/16/2022]
Abstract
Although type I interferon (IFN-I) is thought to be beneficial against microbial infections, persistent viral infections are characterized by high interferon signatures suggesting that IFN-I signaling may promote disease pathogenesis. During persistent lymphocytic choriomeningitis virus (LCMV) infection, IFNα and IFNβ are highly induced early after infection, and blocking IFN-I receptor (IFNAR) signaling promotes virus clearance. We assessed the specific roles of IFNβ versus IFNα in controlling LCMV infection. While blockade of IFNβ alone does not alter early viral dissemination, it is important in determining lymphoid structure, lymphocyte migration, and anti-viral T cell responses that lead to accelerated virus clearance, approximating what occurs during attenuation of IFNAR signaling. Comparatively, blockade of IFNα was not associated with improved viral control, but with early dissemination of virus. Thus, despite their use of the same receptor, IFNβ and IFNα have unique and distinguishable biologic functions, with IFNβ being mainly responsible for promoting viral persistence.
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Affiliation(s)
- Cherie T Ng
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Brian M Sullivan
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - John R Teijaro
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Andrew M Lee
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Megan Welch
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Stephanie Rice
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Kathleen C F Sheehan
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Robert D Schreiber
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Michael B A Oldstone
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA.
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50
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Abstract
The family Arenaviridae currently comprises over 20 viral species, each of them associated with a main rodent species as the natural reservoir and in one case possibly phyllostomid bats. Moreover, recent findings have documented a divergent group of arenaviruses in captive alethinophidian snakes. Human infections occur through mucosal exposure to aerosols or by direct contact of abraded skin with infectious materials. Arenaviruses merit interest both as highly tractable experimental model systems to study acute and persistent infections and as clinically important human pathogens including Lassa (LASV) and Junin (JUNV) viruses, the causative agents of Lassa and Argentine hemorrhagic fevers (AHFs), respectively, for which there are no FDA-licensed vaccines, and current therapy is limited to an off-label use of ribavirin (Rib) that has significant limitations. Arenaviruses are enveloped viruses with a bi-segmented negative strand (NS) RNA genome. Each genome segment, L (ca 7.3 kb) and S (ca 3.5 kb), uses an ambisense coding strategy to direct the synthesis of two polypeptides in opposite orientation, separated by a noncoding intergenic region (IGR). The S genomic RNA encodes the virus nucleoprotein (NP) and the precursor (GPC) of the virus surface glycoprotein that mediates virus receptor recognition and cell entry via endocytosis. The L genome RNA encodes the viral RNA-dependent RNA polymerase (RdRp, or L polymerase) and the small (ca 11 kDa) RING finger protein Z that has functions of a bona fide matrix protein including directing virus budding. Arenaviruses were thought to be relatively stable genetically with intra- and interspecies amino acid sequence identities of 90-95 % and 44-63 %, respectively. However, recent evidence has documented extensive arenavirus genetic variability in the field. Moreover, dramatic phenotypic differences have been documented among closely related LCMV isolates. These data provide strong evidence of viral quasispecies involvement in arenavirus adaptability and pathogenesis. Here, we will review several aspects of the molecular biology of arenaviruses, phylogeny and evolution, and quasispecies dynamics of arenavirus populations for a better understanding of arenavirus pathogenesis, as well as for the development of novel antiviral strategies to combat arenavirus infections.
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Affiliation(s)
- Esteban Domingo
- Campus de Cantoblanco, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
| | - Peter Schuster
- The Santa Fe Institute, Santa Fe, NM, USA and Institut f. Theoretische Chemie, Universität Wien, Vienna, Austria
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