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Lorant AK, Yoshida AE, Gilbertson EA, Chu T, Stefani C, Acharya M, Hamerman JA, Lacy-Hulbert A. Integrin αvβ3 Limits Cytokine Production by Plasmacytoid Dendritic Cells and Restricts TLR-Driven Autoimmunity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2024; 212:1680-1692. [PMID: 38607278 PMCID: PMC11105983 DOI: 10.4049/jimmunol.2300290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 03/20/2024] [Indexed: 04/13/2024]
Abstract
Plasmacytoid dendritic cells (pDCs) are strongly implicated as a major source of IFN-I in systemic lupus erythematosus (SLE), triggered through TLR-mediated recognition of nucleic acids released from dying cells. However, relatively little is known about how TLR signaling and IFN-I production are regulated in pDCs. In this article, we describe a role for integrin αvβ3 in regulating TLR responses and IFN-I production by pDCs in mouse models. We show that αv and β3-knockout pDCs produce more IFN-I and inflammatory cytokines than controls when stimulated through TLR7 and TLR9 in vitro and in vivo. Increased cytokine production was associated with delayed acidification of endosomes containing TLR ligands, reduced LC3 conjugation, and increased TLR signaling. This dysregulated TLR signaling results in activation of B cells and promotes germinal center (GC) B cell and plasma cell expansion. Furthermore, in a mouse model of TLR7-driven lupus-like disease, deletion of αvβ3 from pDCs causes accelerated autoantibody production and pathology. We therefore identify a pDC-intrinsic role for αvβ3 in regulating TLR signaling and preventing activation of autoreactive B cells. Because αvβ3 serves as a receptor for apoptotic cells and cell debris, we hypothesize that this regulatory mechanism provides important contextual cues to pDCs and functions to limit responses to self-derived nucleic acids.
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Affiliation(s)
- Alina K Lorant
- Benaroya Research Institute at Virginia Mason; Seattle, WA, USA 98101
- Department of Immunology, University of Washington; Seattle, WA, USA 98109
| | - Anna E Yoshida
- Benaroya Research Institute at Virginia Mason; Seattle, WA, USA 98101
| | | | - Talyn Chu
- Benaroya Research Institute at Virginia Mason; Seattle, WA, USA 98101
| | - Caroline Stefani
- Benaroya Research Institute at Virginia Mason; Seattle, WA, USA 98101
| | - Mridu Acharya
- Seattle Children’s Research Institute, Seattle, WA, USA 98105
| | - Jessica A Hamerman
- Benaroya Research Institute at Virginia Mason; Seattle, WA, USA 98101
- Department of Immunology, University of Washington; Seattle, WA, USA 98109
| | - Adam Lacy-Hulbert
- Benaroya Research Institute at Virginia Mason; Seattle, WA, USA 98101
- Department of Immunology, University of Washington; Seattle, WA, USA 98109
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2
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Zubair M, Wang J, Yu Y, Rasheed MA, Faisal M, Dawood AS, Ashraf M, Shao G, Feng Z, Xiong Q. Conserved Domains in Variable Surface Lipoproteins A-G of Mycoplasma hyorhinis May Serve as Probable Multi-Epitope Candidate Vaccine: Computational Reverse Vaccinology Approach. Vet Sci 2023; 10:557. [PMID: 37756079 PMCID: PMC10535464 DOI: 10.3390/vetsci10090557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/09/2023] [Accepted: 08/30/2023] [Indexed: 09/28/2023] Open
Abstract
Mycoplasma hyorhinis (M. hyorhinis) is responsible for infections in the swine population. Such infections are usually cured by using antimicrobials and lead to develop resistance. Until now, there has been no effective vaccine to eradicate the disease. This study used conserved domains found in seven members of the variable lipoprotein (VlpA-G) family in order to design a multi-epitope candidate vaccine (MEV) against M. hyorhinis. The immunoinformatics approach was followed to predict epitopes, and a vaccine construct consisting of an adjuvant, two B cell epitopes, two HTL epitopes, and one CTL epitope was designed. The suitability of the vaccine construct was identified by its non-allergen, non-toxic, and antigenic nature. A molecular dynamic simulation was executed to assess the stability of the TLR2 docked structure. An immune simulation showed a high immune response toward the antigen. The protein sequence was reverse-translated, and codons were optimized to gain a high expression level in E. coli. The proposed vaccine construct may be a candidate for a multi-epitope vaccine. Experimental validation is required in future to test the safety and efficacy of the hypothetical candidate vaccine.
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Affiliation(s)
- Muhammad Zubair
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
| | - Jia Wang
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
| | - Yanfei Yu
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Muhammad Asif Rasheed
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Islamabad 45550, Pakistan;
| | - Muhammad Faisal
- Division of Hematology, Department of Medicine, The Ohio State University College of Medicine, The Ohio State University Comprehensive Cancer Center, Columbus, OH 43210, USA;
| | - Ali Sobhy Dawood
- The State Key Laboratory of Agricultural Microbiology, Department of Preventive Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China;
- Faculty of Veterinary Medicine, University of Sadat City, Sadat City 32897, Egypt
| | - Muhammad Ashraf
- Institute of Microbiology, University of Agriculture Faisalabad, Faisalabad 37000, Pakistan;
| | - Guoqing Shao
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Zhixin Feng
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
| | - Qiyan Xiong
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210000, China; (M.Z.); (J.W.); (Y.Y.); (G.S.); (Z.F.)
- GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- School of Life Sciences, Jiangsu University, Zhenjiang 212013, China
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3
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Xiong X, Yang H, Ding C, Qin B, Deng Y, Xiong L, Liu X, Li Y, Xiao T, Lv Z. Functional and expression analysis reveals the involvement of integrin αvβ3 in antiviral immunity of grass carp (Ctenopharyngodon idella). FISH & SHELLFISH IMMUNOLOGY 2022; 129:52-63. [PMID: 35995370 DOI: 10.1016/j.fsi.2022.08.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 08/01/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Integrins are α-β heterodimeric cell receptors that can bind the protein components of pathogens, and play crucial roles in mammalian immune responses, but the immune functions mediated by integrins remains largely unknown in teleost fish. In this study, an integrin αvβ3 (GCαvβ3) originally assembled by αv (GCαv) and β3 (GCβ3) subunits, was identified from a teleost fish grass carp Ctenopharyngodon idella. The pairwise alignment analyses showed that the amino acid sequences of GCαv and GCβ3 shared high similarity (75.2-95.1%) and identity (58.6-90.7%) with their homologs from other vertebrates. Both GCαv and GCβ3 harbored the conserved protein domains and motifs, and were clustered in fish branch of the phylogenetic tree containing the counterparts from various vertebrates. Co-immunoprecipitation displayed that GCβ3 could interact with the grass carp reovirus (GCRV) outer capsid protein VP5. Two incubation experiments revealed that the interaction of GCRV or VP5 proteins with GCβ3 could induce the expressions of type I interferons (IFNs) including IFN2 and IFN3 in grass carp ovary cell line. The functional analysis demonstrated that GCαvβ3 served as a receptor of viral protein components to be involved in antiviral immunity as human integrin αvβ3 did. In addition, both GCαv and GCβ3 were significantly upregulated in various tissues of grass carp after GCRV infection. This study might provide fundamental basis for understanding the molecular characteristics and immune functions of GCαvβ3, and offer a new insight into the antiviral immune mechanism specific to the integrins in grass carp.
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Affiliation(s)
- Xiaoqing Xiong
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; College of Animal Science and Technology, Hunan Agricultural University, Changsha, 410128, China
| | - Hong Yang
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; College of Animal Science and Technology, Hunan Agricultural University, Changsha, 410128, China
| | - Chunhua Ding
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; College of Animal Science and Technology, Hunan Agricultural University, Changsha, 410128, China
| | - Beibei Qin
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; College of Animal Science and Technology, Hunan Agricultural University, Changsha, 410128, China
| | - Yadong Deng
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; College of Animal Science and Technology, Hunan Agricultural University, Changsha, 410128, China
| | - Liming Xiong
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; College of Animal Science and Technology, Hunan Agricultural University, Changsha, 410128, China
| | - Xiaoyan Liu
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China
| | - Yaoguo Li
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China
| | - Tiaoyi Xiao
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China.
| | - Zhao Lv
- Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China.
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Robles JP, Zamora M, Adan-Castro E, Siqueiros-Marquez L, Martinez de la Escalera G, Clapp C. The spike protein of SARS-CoV-2 induces endothelial inflammation through integrin α5β1 and NF-κB signaling. J Biol Chem 2022; 298:101695. [PMID: 35143839 PMCID: PMC8820157 DOI: 10.1016/j.jbc.2022.101695] [Citation(s) in RCA: 64] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 01/24/2022] [Accepted: 01/28/2022] [Indexed: 12/14/2022] Open
Abstract
Vascular endothelial cells (ECs) form a critical interface between blood and tissues that maintains whole-body homeostasis. In COVID-19, disruption of the EC barrier results in edema, vascular inflammation, and coagulation, hallmarks of this severe disease. However, the mechanisms by which ECs are dysregulated in COVID-19 are unclear. Here, we show that the spike protein of SARS-CoV-2 alone activates the EC inflammatory phenotype in a manner dependent on integrin ⍺5β1 signaling. Incubation of human umbilical vein ECs with whole spike protein, its receptor-binding domain, or the integrin-binding tripeptide RGD induced the nuclear translocation of NF-κB and subsequent expression of leukocyte adhesion molecules (VCAM1 and ICAM1), coagulation factors (TF and FVIII), proinflammatory cytokines (TNF⍺, IL-1β, and IL-6), and ACE2, as well as the adhesion of peripheral blood leukocytes and hyperpermeability of the EC monolayer. In addition, inhibitors of integrin ⍺5β1 activation prevented these effects. Furthermore, these vascular effects occur in vivo, as revealed by the intravenous administration of spike, which increased expression of ICAM1, VCAM1, CD45, TNFα, IL-1β, and IL-6 in the lung, liver, kidney, and eye, and the intravitreal injection of spike, which disrupted the barrier function of retinal capillaries. We suggest that the spike protein, through its RGD motif in the receptor-binding domain, binds to integrin ⍺5β1 in ECs to activate the NF-κB target gene expression programs responsible for vascular leakage and leukocyte adhesion. These findings uncover a new direct action of SARS-CoV-2 on EC dysfunction and introduce integrin ⍺5β1 as a promising target for treating vascular inflammation in COVID-19.
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Affiliation(s)
- Juan Pablo Robles
- Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Querétaro, México.
| | - Magdalena Zamora
- Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Querétaro, México
| | - Elva Adan-Castro
- Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Querétaro, México
| | | | | | - Carmen Clapp
- Instituto de Neurobiología, Universidad Nacional Autónoma de México (UNAM), Querétaro, México
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dos Reis VP, Keller M, Schmidt K, Ulrich RG, Groschup MH. αVβ3 Integrin Expression Is Essential for Replication of Mosquito and Tick-Borne Flaviviruses in Murine Fibroblast Cells. Viruses 2021; 14:v14010018. [PMID: 35062222 PMCID: PMC8780171 DOI: 10.3390/v14010018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/17/2021] [Accepted: 12/20/2021] [Indexed: 12/16/2022] Open
Abstract
The Flavivirus genus includes a number of important viruses that are pathogenic to humans and animals and are responsible for outbreaks across the globe. Integrins, a family of heterodimeric transmembrane molecules expressed in all nucleated cells mediate critical functions of cell physiology and cell cycle. Integrins were previously postulated to be involved in flavivirus entry and to modulate flavivirus replication efficiency. In the present study, mouse embryonic fibroblasts (MEF), lacking the expression of αVβ3 integrin (MEF-αVβ3−/−), were infected with four different flaviviruses, namely yellow fever virus (YFV), West Nile virus (WNV), Usutu virus (USUV) and Langat virus (LGTV). The effects of the αVβ3 integrin absence in double-knockout MEF-αVβ3−/− on flavivirus binding, internalization and replication were compared to the respective wild-type cells. Binding to the cell surface for all four flaviviruses was not affected by the ablation of αVβ3 integrin, whereas internalization of USUV and WNV was slightly affected by the loss of αVβ3 integrin expression. Most interestingly, the deletion of αVβ3 integrin strongly impaired replication of all flaviviruses with a reduction of up to 99% on virus yields and a strong reduction on flavivirus anti-genome RNA synthesis. In conclusion, our results demonstrate that αVβ3 integrin expression in flavivirus-susceptible cell lines enhances the flavivirus replication.
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Affiliation(s)
- Vinicius Pinho dos Reis
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (V.P.d.R.); (M.K.); (R.G.U.)
- Institute for Virology, Philipps University Marburg, Hans-Meerwein-Straße 2, 35043 Marburg, Germany
| | - Markus Keller
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (V.P.d.R.); (M.K.); (R.G.U.)
| | - Katja Schmidt
- Microbiological Diagnostics, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany;
| | - Rainer Günter Ulrich
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (V.P.d.R.); (M.K.); (R.G.U.)
- Deutsches Zentrum für Infektionsforschung(DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Martin Hermann Groschup
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany; (V.P.d.R.); (M.K.); (R.G.U.)
- Deutsches Zentrum für Infektionsforschung(DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, Südufer 10, 17493 Greifswald-Insel Riems, Germany
- Correspondence: ; Tel.: +49-38351-71163
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ACE2 and Innate Immunity in the Regulation of SARS-CoV-2-Induced Acute Lung Injury: A Review. Int J Mol Sci 2021; 22:ijms222111483. [PMID: 34768911 PMCID: PMC8583933 DOI: 10.3390/ijms222111483] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/21/2021] [Accepted: 10/21/2021] [Indexed: 01/08/2023] Open
Abstract
Despite the protracted battle against coronavirus acute respiratory infection (COVID-19) and the rapid evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), no specific and effective drugs have to date been reported. Angiotensin-converting enzyme 2 (ACE2) is a zinc metalloproteinase and a critical modulator of the renin-angiotensin system (RAS). In addition, ACE2 has anti-inflammatory and antifibrosis functions. ACE has become widely known in the past decade as it has been identified as the primary receptor for SARS-CoV and SARS-CoV-2, being closely associated with their infection. SARS-CoV-2 primarily targets the lung, which induces a cytokine storm by infecting alveolar cells, resulting in tissue damage and eventually severe acute respiratory syndrome. In the lung, innate immunity acts as a critical line of defense against pathogens, including SARS-CoV-2. This review aims to summarize the regulation of ACE2, and lung host cells resist SARS-CoV-2 invasion by activating innate immunity response. Finally, we discuss ACE2 as a therapeutic target, providing reference and enlightenment for the clinical treatment of COVID-19.
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Gern OL, Mulenge F, Pavlou A, Ghita L, Steffen I, Stangel M, Kalinke U. Toll-like Receptors in Viral Encephalitis. Viruses 2021; 13:v13102065. [PMID: 34696494 PMCID: PMC8540543 DOI: 10.3390/v13102065] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/06/2021] [Accepted: 10/08/2021] [Indexed: 12/23/2022] Open
Abstract
Viral encephalitis is a rare but serious syndrome. In addition to DNA-encoded herpes viruses, such as herpes simplex virus and varicella zoster virus, RNA-encoded viruses from the families of Flaviviridae, Rhabdoviridae and Paramyxoviridae are important neurotropic viruses. Whereas in the periphery, the role of Toll-like receptors (TLR) during immune stimulation is well understood, TLR functions within the CNS are less clear. On one hand, TLRs can affect the physiology of neurons during neuronal progenitor cell differentiation and neurite outgrowth, whereas under conditions of infection, the complex interplay between TLR stimulated neurons, astrocytes and microglia is just on the verge of being understood. In this review, we summarize the current knowledge about which TLRs are expressed by cell subsets of the CNS. Furthermore, we specifically highlight functional implications of TLR stimulation in neurons, astrocytes and microglia. After briefly illuminating some examples of viral evasion strategies from TLR signaling, we report on the current knowledge of primary immunodeficiencies in TLR signaling and their consequences for viral encephalitis. Finally, we provide an outlook with examples of TLR agonist mediated intervention strategies and potentiation of vaccine responses against neurotropic virus infections.
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Affiliation(s)
- Olivia Luise Gern
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625 Hannover, Germany; (F.M.); (A.P.); (L.G.); (U.K.)
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany
- Correspondence:
| | - Felix Mulenge
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625 Hannover, Germany; (F.M.); (A.P.); (L.G.); (U.K.)
| | - Andreas Pavlou
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625 Hannover, Germany; (F.M.); (A.P.); (L.G.); (U.K.)
- Clinical Neuroimmunology and Neurochemistry, Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
- Center for Systems Neuroscience, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
| | - Luca Ghita
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625 Hannover, Germany; (F.M.); (A.P.); (L.G.); (U.K.)
- Division of Infectious Diseases and Geographic Medicine, Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Imke Steffen
- Department of Biochemistry and Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany;
| | - Martin Stangel
- Translational Medicine, Novartis Institute for Biomedical Research (NIBR), 4056 Basel, Switzerland;
| | - Ulrich Kalinke
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625 Hannover, Germany; (F.M.); (A.P.); (L.G.); (U.K.)
- Cluster of Excellence—Resolving Infection Susceptibility (RESIST, EXC 2155), Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany
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Integrin β3 Modulates TLR4-Mediated Inflammation by Regulation of CD14 Expression in Macrophages in Septic Condition. Shock 2021; 53:335-343. [PMID: 31135705 DOI: 10.1097/shk.0000000000001383] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Sepsis is a major challenge in clinical practice and responsible for high mortality. Recent studies indicated that integrins participated in toll-like-receptor (TLR)-mediated innate immunity. In the present study, we investigated the mechanism of integrin β3 and TLR4 signaling using a cecal ligation and puncture (CLP)-induced sepsis and lipopolysaccharide (LPS)-treated macrophage cell model. In a lethal CLP model, the survival rate of integrin β3 mice was higher than that of wild-type mice. The levels of alanine aminotransferase, aspartate transaminase, creatinine, blood urea nitrogen , and lactate dehydrogenase in the serum and cluster of differentiation 14 (CD14) protein expression in the tissues were significantly decreased in integrin β3 mice. A similar effect with regard to CD14 down-regulation was observed in septic TLR4 mice. In wild-type macrophages, the inhibition of integrin β3 by P11 or with a specific antibody, inhibited TNF-α, and IL-6 release at the early time period of LPS stimulation. However, during the late periods of LPS stimulation this effect was not noted. CD14 expression levels had no change in such treatment. In contract, LPS-induced TNF-α and IL-6 release and LPS-induced CD14 expression were significantly decreased in integrin β3macrophages. The inhibition of the TLR4 pathway by TAK-242, or in TLR4 mutant macrophages abolished LPS-induced CD14 expression. Integrin β3 pathway activation by vitronectin exhibited no effect in CD14 expression. Furthermore, recombinant CD14 protein stimulation reversed integrin β3 deficiency and caused lower TNF-α and IL-6 release. Moreover, the molecular interaction of TLR4 and integrin β3 was significantly increased following LPS stimulation. In conclusion, integrin β3 positively regulated TLR4-mediated inflammatory responses via CD14 expression in macrophages in septic condition. Specifically targeting integrin β3/TLR4-CD14 signaling pathway may be a potential treatment strategy for polymicrobial sepsis.
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9
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Jakhmola S, Indari O, Kashyap D, Varshney N, Das A, Manivannan E, Jha HC. Mutational analysis of structural proteins of SARS-CoV-2. Heliyon 2021; 7:e06572. [PMID: 33778179 PMCID: PMC7980187 DOI: 10.1016/j.heliyon.2021.e06572] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 01/16/2021] [Accepted: 03/17/2021] [Indexed: 02/07/2023] Open
Abstract
SARS-CoV-2 transmissibility is higher than that of other human coronaviruses; therefore, it poses a threat to the populated communities. We investigated mutations among envelope (E), membrane (M), and spike (S) proteins from different isolates of SARS-CoV-2 and plausible signaling influenced by mutated virus in a host. We procured updated protein sequences from the NCBI virus database. Mutations were analyzed in the retrieved sequences of the viral proteins through multiple sequence alignment. Additionally, the data was subjected to ScanPROSITE to analyse if the mutations generated a relevant sequence for host signaling. Unique mutations in E, M, and S proteins resulted in modification sites like PKC phosphorylation and N-myristoylation sites. Based on structural analysis, our study revealed that the D614G mutation in the S protein diminished the interaction with T859 and K854 of adjacent chains. Moreover, the S protein of SARS-CoV-2 consists of an Arg-Gly-Asp (RGD) tripeptide sequence, which could potentially interact with various members of integrin family receptors. RGD sequence in S protein might aid in the initial virus attachment. We speculated crucial host pathways which the mutated isolates of SARS-CoV-2 may alter like PKC, Src, and integrin mediated signaling pathways. PKC signaling is known to influence the caveosome/raft pathway which is critical for virus entry. Additionally, the myristoylated proteins might activate NF-κB, a master molecule of inflammation. Thus the mutations may contribute to the disease pathogenesis and distinct lung pathophysiological changes. Further the frequently occurring mutations in the protein can be studied for possible therapeutic interventions.
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Affiliation(s)
- Shweta Jakhmola
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Omkar Indari
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Dharmendra Kashyap
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Nidhi Varshney
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Ayan Das
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | | | - Hem Chandra Jha
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
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Lannoy V, Côté-Biron A, Asselin C, Rivard N. Phosphatases in toll-like receptors signaling: the unfairly-forgotten. Cell Commun Signal 2021; 19:10. [PMID: 33494775 PMCID: PMC7829650 DOI: 10.1186/s12964-020-00693-9] [Citation(s) in RCA: 12] [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: 09/24/2020] [Accepted: 12/01/2020] [Indexed: 02/07/2023] Open
Abstract
Over the past 2 decades, pattern recognition receptors (PRRs) have been shown to be on the front line of many illnesses such as autoimmune, inflammatory, and neurodegenerative diseases as well as allergies and cancer. Among PRRs, toll-like receptors (TLRs) are the most studied family. Dissecting TLRs signaling turned out to be advantageous to elaborate efficient treatments to cure autoimmune and chronic inflammatory disorders. However, a broad understanding of TLR effectors is required to propose a better range of cures. In addition to kinases and E3 ubiquitin ligases, phosphatases emerge as important regulators of TLRs signaling mediated by NF-κB, type I interferons (IFN I) and Mitogen-Activated Protein Kinases signaling pathways. Here, we review recent knowledge on TLRs signaling modulation by different classes and subclasses of phosphatases. Thus, it becomes more and more evident that phosphatases could represent novel therapeutic targets to control pathogenic TLRs signaling. Video Abstract.
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Affiliation(s)
- Valérie Lannoy
- Department of Immunology and Cell Biology, Cancer Research Pavilion, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3201, rue Jean Mignault, Sherbrooke, QC, J1E4K8, Canada
| | - Anthony Côté-Biron
- Department of Immunology and Cell Biology, Cancer Research Pavilion, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3201, rue Jean Mignault, Sherbrooke, QC, J1E4K8, Canada
| | - Claude Asselin
- Department of Immunology and Cell Biology, Cancer Research Pavilion, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3201, rue Jean Mignault, Sherbrooke, QC, J1E4K8, Canada
| | - Nathalie Rivard
- Department of Immunology and Cell Biology, Cancer Research Pavilion, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3201, rue Jean Mignault, Sherbrooke, QC, J1E4K8, Canada.
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11
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de Barros BCSC, Almeida BR, Suzuki E. Paracoccidioides brasiliensis downmodulates α3 integrin levels in human lung epithelial cells in a TLR2-dependent manner. Sci Rep 2020; 10:19483. [PMID: 33173103 PMCID: PMC7655819 DOI: 10.1038/s41598-020-76557-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 10/29/2020] [Indexed: 02/05/2023] Open
Abstract
Paracoccidioidomycosis (PCM) is the most prevalent systemic mycosis in Latin America and may be caused by the species Paracoccidioides brasiliensis. In the lungs, this fungus interacts with epithelial cells, activating host cell signalling pathways, resulting in the production of inflammatory mediators. This event may be initiated through the activation of Pattern-Recognition Receptors such as Toll-like Receptors (TLRs). By interacting with cell wall components, TLR2 is frequently related to fungal infections. In this work, we show that, after 24 h post-infection with P. brasiliensis, A549 lung epithelial cells presented higher TLR2 levels, which is important for IL-8 secretion. Besides, integrins may also participate in pathogen recognition by host cells. We verified that P. brasiliensis increased α3 integrin levels in A549 cells after 5 h of infection and promoted interaction between this receptor and TLR2. However, after 24 h, surprisingly, we verified a decrease of α3 integrin levels, which was dependent on direct contact between fungi and epithelial cells. Likewise, we observed that TLR2 is important to downmodulate α3 integrin levels after 24 h of infection. Thus, P. brasiliensis can modulate the host inflammatory response by exploiting host cell receptors and cell signalling pathways.
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Affiliation(s)
| | - Bruna Rocha Almeida
- Department of Microbiology, Immunology, and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, 04023-062, Brazil
| | - Erika Suzuki
- Department of Microbiology, Immunology, and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, 04023-062, Brazil.
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12
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Gruber EJ, Leifer CA. Molecular regulation of TLR signaling in health and disease: mechano-regulation of macrophages and TLR signaling. Innate Immun 2020; 26:15-25. [PMID: 31955624 PMCID: PMC6974875 DOI: 10.1177/1753425919838322] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Immune cells encounter tissues with vastly different biochemical and physical
characteristics. Much of the research emphasis has focused on the role of
cytokines and chemokines in regulating immune cell function, but the role of the
physical microenvironment has received considerably less attention. The tissue
mechanics, or stiffness, of healthy tissues varies dramatically from soft
adipose tissue and brain to stiff cartilage and bone. Tissue mechanics also
change due to fibrosis and with diseases such as atherosclerosis or cancer. The
process by which cells sense and respond to their physical microenvironment is
called mechanotransduction. Here we review mechanotransduction in
immunologically important diseases and how physical characteristics of tissues
regulate immune cell function, with a specific emphasis on mechanoregulation of
macrophages and TLR signaling.
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Affiliation(s)
- Erika J Gruber
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, USA
| | - Cynthia A Leifer
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, USA
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Abstract
Tumors utilize a number of effective strategies, including the programmed death 1/PD ligand 1 (PD-1/PD-L1) axis, to evade immune-mediated control of their growth. PD-L1 expression is mainly induced by IFN receptor signaling or constitutively induced. Integrins are an abundantly expressed class of proteins which play multiple deleterious roles in cancer and exert proangiogenic and prosurvival activities. We asked whether αvβ3-integrin positively regulates PD-L1 expression and the anticancer immune response. We report that αvβ3-integrin regulated constitutive and IFN-induced PD-L1 expression in human and murine cancerous and noncancerous cells. αvβ3-integrin targeted STAT1 through its signaling C tail. The implantation of β3-integrin-depleted tumor cells led to a dramatic decrease in the growth of primary tumors, which exhibited reduced PD-L1 expression and became immunologically hot, with increased IFNγ content and CD8+ cell infiltration. In addition, the implantation of β3-integrin-depleted tumors elicited an abscopal immunotherapeutic effect measured as protection from the challenge tumor and durable splenocyte and serum reactivity to B16 cell antigens. These modifications to the immunosuppressive microenvironment primed cells for checkpoint (CP) blockade. When combined with anti-PD-1, β3-integrin depletion led to durable therapy and elicited an abscopal immunotherapeutic effect. We conclude that in addition to its previously known roles, αvβ3-integrin serves as a critical component of the cancer immune evasion strategy and can be an effective immunotherapy target.
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Gruber E, Heyward C, Cameron J, Leifer C. Toll-like receptor signaling in macrophages is regulated by extracellular substrate stiffness and Rho-associated coiled-coil kinase (ROCK1/2). Int Immunol 2019; 30:267-278. [PMID: 29800294 DOI: 10.1093/intimm/dxy027] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 04/04/2018] [Indexed: 02/07/2023] Open
Abstract
Macrophages participate in immunity, tissue repair and tissue homeostasis. Activation of Toll-like receptors (TLRs) by conserved exogenous or endogenous structures initiates signaling cascades that result in the release of cytokines such as tumor necrosis factor α (TNFα). Extracellular substrate stiffness is known to regulate functions of non-immune cells through a process called mechanotransduction, yet less is known about how physical cues affect macrophage function or TLR signaling. To investigate this question, we cultured murine primary bone marrow-derived macrophages (BMMs) and RAW264.7 cells on fibronectin-coated polyacrylamide (PA) gels of defined stiffnesses (1, 20 and 150 kPa) that approximate the physical properties of physiologic tissues. BMMs on all gels were smaller and more circular than those on rigid glass. Macrophages on intermediate stiffness 20 kPa PA gels were slightly larger and less circular than those on either 1 or 150 kPa. Secretion of the pro-inflammatory cytokine, TNFα, in response to stimulation of TLR4 and TLR9 was increased in macrophages grown on soft gels versus more rigid gels, particularly for BMMs. Inhibition of the rho-associated coiled-coil kinase 1/2 (ROCK1/2), key mediators in cell contractility and mechanotransduction, enhanced release of TNFα in response to stimulation of TLR4. ROCK1/2 inhibition enhanced phosphorylation of the TLR downstream signaling molecules, p38, ERK1/2 and NFκB. Our data indicate that physical cues from the extracellular environment regulate macrophage morphology and TLR signaling. These findings have important implications in the regulation of macrophage function in diseased tissues and offer a novel pharmacological target for the manipulation of macrophage function in vivo.
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Affiliation(s)
- Erika Gruber
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Christa Heyward
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Jody Cameron
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Cynthia Leifer
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
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15
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Loss of transglutaminase 2 sensitizes for diet-induced obesity-related inflammation and insulin resistance due to enhanced macrophage c-Src signaling. Cell Death Dis 2019; 10:439. [PMID: 31165747 PMCID: PMC6549190 DOI: 10.1038/s41419-019-1677-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/09/2019] [Accepted: 05/19/2019] [Indexed: 12/11/2022]
Abstract
Transglutaminase 2 (TG2) is a multifunctional protein that promotes clearance of apoptotic cells (efferocytosis) acting as integrin β3 coreceptor. Accumulating evidence indicates that defective efferocytosis contributes to the development of chronic inflammatory diseases. Obesity is characterized by the accumulation of dead adipocytes and inflammatory macrophages in the adipose tissue leading to obesity-related metabolic syndrome. Here, we report that loss of TG2 from bone marrow-derived cells sensitizes for high fat diet (HFD)-induced pathologies. We find that metabolically activated TG2 null macrophages express more phospho-Src and integrin β3, unexpectedly clear dying adipocytes more efficiently via lysosomal exocytosis, but produce more pro-inflammatory cytokines than the wild type ones. Anti-inflammatory treatment with an LXR agonist reverts the HFD-induced phenotype in mice lacking TG2 in bone marrow-derived cells with less hepatic steatosis than in wild type mice proving enhanced lipid clearance. Thus it is interesting to speculate whether LXR agonist treatment together with enhancing lysosomal exocytosis could be a beneficial therapeutic strategy in obesity.
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Tognarelli EI, Palomino TF, Corrales N, Bueno SM, Kalergis AM, González PA. Herpes Simplex Virus Evasion of Early Host Antiviral Responses. Front Cell Infect Microbiol 2019; 9:127. [PMID: 31114761 PMCID: PMC6503643 DOI: 10.3389/fcimb.2019.00127] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 04/10/2019] [Indexed: 12/21/2022] Open
Abstract
Herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) have co-evolved with humans for thousands of years and are present at a high prevalence in the population worldwide. HSV infections are responsible for several illnesses including skin and mucosal lesions, blindness and even life-threatening encephalitis in both, immunocompetent and immunocompromised individuals of all ages. Therefore, diseases caused by HSVs represent significant public health burdens. Similar to other herpesviruses, HSV-1 and HSV-2 produce lifelong infections in the host by establishing latency in neurons and sporadically reactivating from these cells, eliciting recurrences that are accompanied by viral shedding in both, symptomatic and asymptomatic individuals. The ability of HSVs to persist and recur in otherwise healthy individuals is likely given by the numerous virulence factors that these viruses have evolved to evade host antiviral responses. Here, we review and discuss molecular mechanisms used by HSVs to evade early innate antiviral responses, which are the first lines of defense against these viruses. A comprehensive understanding of how HSVs evade host early antiviral responses could contribute to the development of novel therapies and vaccines to counteract these viruses.
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Affiliation(s)
- Eduardo I Tognarelli
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Tomás F Palomino
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás Corrales
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Susan M Bueno
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexis M Kalergis
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Endocrinología, Facultad de Medicina, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo A González
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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Innate Immune Mechanisms and Herpes Simplex Virus Infection and Disease. ADVANCES IN ANATOMY EMBRYOLOGY AND CELL BIOLOGY 2018; 223:49-75. [PMID: 28528439 DOI: 10.1007/978-3-319-53168-7_3] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Innate immune responses play a major role in the control of herpes simplex virus (HSV) infections, and a multiplicity of mechanisms have emerged as a result of human evolution to sense and respond to HSV infections. HSV in turn has evolved a number of ways to evade immune detection and to blunt human innate immune responses. In this review, we summarize the major host innate immune mechanisms and the HSV evasion mechanisms that have evolved. We further discuss how disease can result if this equilibrium between virus and host response is disrupted.
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18
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Campadelli-Fiume G. Spotlight on… Gabriella Campadelli-Fiume. FEMS Microbiol Lett 2018; 365:5002024. [PMID: 29873707 PMCID: PMC5967523 DOI: 10.1093/femsle/fny019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 01/26/2018] [Indexed: 12/02/2022] Open
Affiliation(s)
- Gabriella Campadelli-Fiume
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Via San Giacomo, 12 40126 Bologna, Italy
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19
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Rider PJF, Musarrat F, Nabil R, Naidu S, Kousoulas KG. First Impressions-the Potential of Altering Initial Host-Virus Interactions for Rational Design of Herpesvirus Vaccine Vectors. CURRENT CLINICAL MICROBIOLOGY REPORTS 2018; 5:55-65. [PMID: 30560044 DOI: 10.1007/s40588-018-0082-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Purpose The earliest host-virus interactions occur during virus attachment and entry into cells. These initial steps in the virus lifecycle influence the outcome of infection beyond delivery of the viral genome into the cell. Herpesviruses alter host signaling pathways and processes during attachment and entry to facilitate virus infection and modulate innate immune responses. We suggest in this review that understanding these early signaling events may inform the rational design of therapeutic and prevention strategies for herpesvirus infection, as well as the engineering of viral vectors for immunotherapy purposes. Recent Findings Recent reports demonstrate that modulation of Herpes Simplex Virus Type-1 (HSV-1) entry results in unexpected enhancement of antiviral immune responses. Summary A variety of evidence suggests that herpesviruses promote specific cellular signaling responses that facilitate viral replication after binding to cell surfaces, as well as during virus entry. Of particular interest is the ability of the virus to alter innate immune responses through these cellular signaling events. Uncovering the underlying immune evasion strategies may lead to the design of live-attenuated vaccines that can generate robust and protective anti-viral immune responses against herpesviruses. These adjuvant properties may be extended to a variety of heterologous antigens expressed by herpesviral vectors.
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Affiliation(s)
- Paul J F Rider
- Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge LA
| | - Farhana Musarrat
- Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge LA
| | - Rafiq Nabil
- Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge LA
| | - Shan Naidu
- Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge LA
| | - Konstantin G Kousoulas
- Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge LA
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Saquinavir Ameliorates Liver Warm Ischemia-Reperfusion-Induced Lung Injury via HMGB-1- and P38/JNK-Mediated TLR-4-Dependent Signaling Pathways. Mediators Inflamm 2017; 2017:7083528. [PMID: 29440779 PMCID: PMC5758951 DOI: 10.1155/2017/7083528] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 11/13/2017] [Accepted: 11/22/2017] [Indexed: 12/11/2022] Open
Abstract
Liver ischemia and reperfusion (I/R) induce local and distant tissue injuries, contributing to morbidity and mortality in a wider range of pathologies. This is especially seen under uncontrolled aseptic inflammatory conditions, leading to injury of remote organs, such as lung injury, and even failure. Saquinavir (SQV) is a kind of HIV protease inhibitor that possesses an anti-inflammatory property. In this study, we investigated whether SQV suppresses Toll-like receptor 4- (TLR4-) dependent signaling pathways of high-mobility group box 1 (HMGB1) and P38/JNK, conferring protection against murine liver I/R-induced lung injury. To investigate our hypothesis, C57BL/6 mice and TLR4 knockout mice (TLR4−/−) were used to perform the study. SQV administration markedly attenuated remote lung tissue injury after 1-hour ischemia and 6-hour reperfusion of the liver. To our expectation, SQV attenuated I/R-induced lung edema, hyperpermeability, and pathological injury. The beneficial effects of SQV were associated with decreased levels of circulating and lung tissue inflammatory cytokines, such as IL-6, IL-1β, TNF-α, and iNOS. The protective effect of SQV was also associated with decreased lung tissue expression of HMGB1, TLR-4, and p-P38/JNK, but not p-ERK in wild-type liver I/R mice. Overall, this study demonstrated a new role of SQV, facilitating negative regulation of HMGB1- and P38/JNK-mediated TLR-4-dependent signaling pathways, conferring protection against liver I/R-induced lung injury.
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21
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McKeown-Longo PJ, Higgins PJ. Integration of Canonical and Noncanonical Pathways in TLR4 Signaling: Complex Regulation of the Wound Repair Program. Adv Wound Care (New Rochelle) 2017; 6:320-329. [PMID: 29062589 DOI: 10.1089/wound.2017.0736] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 04/10/2017] [Indexed: 12/17/2022] Open
Abstract
Significance: Chronic inflammation and maladaptive repair contribute to the development of fibrosis that negatively impacts quality of life and organ function. The toll-like receptor (TLR) system is a critical node in the tissue response to both exogenous (pathogen-associated) and endogenous (damage-associated) molecular pattern factors (PAMPs and DAMPs, respectively). The development of novel TLR ligand-, pathway-, and/or target gene-specific therapeutics may have clinical utility in the management of the exuberant inflammatory/fibrotic tissue response to injury without compromising the host defense to pathogens. Recent Advances: DAMP ligands, released upon wounding, and microbial-derived PAMPs interact with several TLRs, and their various coreceptor partners, engaging downstream pathways that include Src family kinases, the epidermal growth factor receptor, integrins and the tumor suppressor phosphatase and tensin homolog (PTEN). Toll-like receptor 4 (TLR4) activation enhances cellular responses to the potent profibrotic cytokine transforming growth factor-β1 (TGF-β1) by attenuating the expression of receptors that inhibit TGF-β1 signaling. Critical Issues: Common as well as unique pathways may be activated by PAMP and DAMP ligands that bind to the repertoire of TLRs on various cell types. Dissecting mechanisms underlying ligand-dependent engagement of this complex, highly interactive, network will provide for adaptation of new and focused therapies directed to the regulation of pathologically significant profibrotic genes. Inherent in this diversity are therapeutic opportunities to modulate the pathophysiologic consequences of persistent TLR signaling. The recently identified involvement of receptor and nonreceptor kinase pathways in TLR signaling may present novel opportunities for pharmacologic intervention. Future Directions: Clarifying the identity and function of DAMP-activated TLR complexes or ligand-binding partners, as well as their engaged downstream effectors and target genes, are key factors in the eventual design of pathway-specific treatment modalities. Such approaches may be tailored to address the spectrum of TLR-initiated pathologies (including localized and persistent inflammation, maladaptive repair/fibrosis) and, perhaps, even titrated to achieve patient-unique beneficial clinical outcomes.
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Affiliation(s)
- Paula J. McKeown-Longo
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, Albany, New York
| | - Paul J. Higgins
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, Albany, New York
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22
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Pattabiraman G, Panchal R, Medvedev AE. The R753Q polymorphism in Toll-like receptor 2 (TLR2) attenuates innate immune responses to mycobacteria and impairs MyD88 adapter recruitment to TLR2. J Biol Chem 2017; 292:10685-10695. [PMID: 28442574 DOI: 10.1074/jbc.m117.784470] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 04/15/2017] [Indexed: 12/28/2022] Open
Abstract
Toll-like receptor 2 (TLR2) plays a critical role in host defenses against mycobacterial infections. The R753Q TLR2 polymorphism has been associated with increased incidence of tuberculosis and infections with non-tuberculous mycobacteria in human populations, but the mechanisms by which this polymorphism affects TLR2 signaling are unclear. In this study, we determined the impact of the R753Q TLR2 polymorphism on macrophage sensing of Mycobacterium smegmatis Upon infection with M. smegmatis, macrophages from knock-in mice harboring R753Q TLR2 expressed lower levels of TNF-α, IL-1β, IL-6, and IL-10 compared with cells from WT mice, but both R753Q TLR2- and WT-derived macrophages exhibited comparable bacterial burdens. The decreased cytokine responses in R753Q TLR2-expressing macrophages were accompanied by impaired phosphorylation of IL-1R-associated kinase 1 (IRAK-1), p38, ERK1/2 MAPKs, and p65 NF-κB, suggesting that the R753Q TLR2 polymorphism alters the functions of the myeloid differentiation primary response protein 88 (MyD88)-IRAK-dependent signaling axis. Supporting this notion, HEK293 cells stably transfected with YFP-tagged R753Q TLR2 displayed reduced recruitment of MyD88 to TLR2, decreased NF-κB activation, and impaired IL-8 expression upon exposure to M. smegmatis Collectively, our results indicate that the R753Q polymorphism alters TLR2 signaling competence, leading to impaired MyD88-TLR2 assembly, reduced phosphorylation of IRAK-1, diminished activation of MAPKs and NF-κB, and deficient induction of cytokines in macrophages infected with M. smegmatis.
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Affiliation(s)
- Goutham Pattabiraman
- From the Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - Rahul Panchal
- From the Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - Andrei E Medvedev
- From the Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut 06030
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23
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Campadelli-Fiume G, Collins-McMillen D, Gianni T, Yurochko AD. Integrins as Herpesvirus Receptors and Mediators of the Host Signalosome. Annu Rev Virol 2016; 3:215-236. [PMID: 27501260 DOI: 10.1146/annurev-virology-110615-035618] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The repertoire of herpesvirus receptors consists of nonintegrin and integrin molecules. Integrins interact with the conserved glycoproteins gH/gL or gB. This interaction is a conserved biology across the Herpesviridae family, likely directed to promote virus entry and endocytosis. Herpesviruses exploit this interaction to execute a range of critical functions that include (a) relocation of nonintegrin receptors (e.g., herpes simplex virus nectin1 and Kaposi's sarcoma-associated herpesvirus EphA2), or association with nonintegrin receptors (i.e., human cytomegalovirus EGFR), to dictate species-specific entry pathways; (b) activation of multiple signaling pathways (e.g., Ca2+ release, c-Src, FAK, MAPK, and PI3K); and (c) association with Rho GTPases, tyrosine kinase receptors, Toll-like receptors, which result in cytoskeletal remodeling, differential cell type targeting, and innate responses. In turn, integrins can be modulated by viral proteins (e.g., Epstein-Barr virus LMPs) to favor spread of transformed cells. We propose that herpesviruses evolved a multipartite entry system to allow interaction with multiple receptors, including integrins, required for their sophisticated life cycle.
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Affiliation(s)
- Gabriella Campadelli-Fiume
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy;
| | - Donna Collins-McMillen
- Department of Microbiology and Immunology, Center for Molecular and Tumor Virology, and Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130;
| | - Tatiana Gianni
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy;
| | - Andrew D Yurochko
- Department of Microbiology and Immunology, Center for Molecular and Tumor Virology, and Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130; .,Feist-Weiller Cancer Center and Center for Excellence in Arthritis and Rheumatology, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130
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24
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Maza PK, Suzuki E. Histoplasma capsulatum-Induced Cytokine Secretion in Lung Epithelial Cells Is Dependent on Host Integrins, Src-Family Kinase Activation, and Membrane Raft Recruitment. Front Microbiol 2016; 7:580. [PMID: 27148251 PMCID: PMC4840283 DOI: 10.3389/fmicb.2016.00580] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 04/08/2016] [Indexed: 01/30/2023] Open
Abstract
Histoplasma capsulatum var. capsulatum is a dimorphic fungus that causes histoplasmosis, a human systemic mycosis with worldwide distribution. In the present work, we demonstrate that H. capsulatum yeasts are able to induce cytokine secretion by the human lung epithelial cell line A549 in integrin- and Src-family kinase (SFK)-dependent manners. This conclusion is supported by small interfering RNA (siRNA) directed to α3 and α5 integrins, and PP2, an inhibitor of SFK activation. siRNA and PP2 reduced IL-6 and IL-8 secretion in H. capsulatum-infected A549 cell cultures. In addition, α3 and α5 integrins from A549 cells were capable of associating with H. capsulatum yeasts, and this fungus promotes recruitment of these integrins and SFKs to A549 cell membrane rafts. Corroborating this finding, membrane raft disruption with the cholesterol-chelator methyl-β-cyclodextrin reduced the levels of integrins and SFKs in these cell membrane domains. Finally, pretreatment of A549 cells with the cholesterol-binding compound, and also a membrane raft disruptor, filipin, significantly reduced IL-6 and IL-8 levels in A549-H.capsulatum cultures. Taken together, these results indicate that H. capsulatum yeasts induce secretion of IL-6 and IL-8 in human lung epithelial cells by interacting with α3 and α5 integrins, recruiting these integrins to membrane rafts, and promoting SFK activation.
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Affiliation(s)
- Paloma K Maza
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
| | - Erika Suzuki
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
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αvβ3 Integrin Boosts the Innate Immune Response Elicited in Epithelial Cells through Plasma Membrane and Endosomal Toll-Like Receptors. J Virol 2016; 90:4243-4248. [PMID: 26842473 DOI: 10.1128/jvi.03175-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 01/27/2016] [Indexed: 01/24/2023] Open
Abstract
We report that αvβ3 integrin strongly affects the innate immune response in epithelial cells. αvβ3 integrin greatly increased the response elicited via plasma membrane Toll-like receptors (TLRs) by herpes simplex virus or bacterial ligands. The endosomal TLR3, not the cytosolic sensor interferon gamma-inducible protein 16 (IFI16), was also boosted by αvβ3 integrin. The boosting was exerted specifically by αvβ3 integrin but not by αvβ6 or αvβ8 integrin. Current and previous work indicates that integrin-TLR cooperation occurs in epithelial and monocytic cells. The TLR response should be considered an integrin-TLR response.
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Snake Venom Disintegrin Inhibits the Activation of Toll-Like Receptors and Alleviates Sepsis through Integrin alphaVbeta3 Blockade. Sci Rep 2016; 6:23387. [PMID: 26987407 PMCID: PMC4796821 DOI: 10.1038/srep23387] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 03/03/2016] [Indexed: 01/13/2023] Open
Abstract
Bacterial infection-induced sepsis is the leading cause of septic inflammatory disease. Rhodostomin (Rn), a snake venom disintegrin, was previously reported to interact with the αVβ3 integrin and the TLR4 on phagocyte in attenuating LPS-induced endotoxemia. In this report, we further evaluated the effects of Rn on TLR2-activated monocytes and its in vivo efficacy. Rn effectively suppressed the adhesion, migration, and cytokine release of Pam3CSK4-activated THP-1 cells. Rn specifically bound to integrin αVβ3 of TLR2-activated THP-1. Integrin αV and Akt siRNA transfection both restrained Pam3CSK4-elicited cytokine release. Rn decreased the Pam3CSK4-induced phosporylation of MAPKs, degradation of IκB and activation of FAK, Akt, c-Src and Syk. The Pam3CSK4-induced translocation of MyD88, a central adaptor of TLR2, to the cell membrane was also inhibited by Rn treatment. In the polymicrobial inflammatory caecal ligation and puncture model, Rn significantly reduced pro-inflammatory cytokine and chemokine release, alleviated tissue injury and elevated survival rate in vivo. Taken together, in addition to inhibiting the activation of TLR4, Rn exhibits anti-inflammatory activity through antagonizing the activation of phagocytes and interrupting the crosstalk between αVβ3 and TLR2-dependent signaling pathways.
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Nita-Lazar M, Banerjee A, Feng C, Vasta GR. Galectins regulate the inflammatory response in airway epithelial cells exposed to microbial neuraminidase by modulating the expression of SOCS1 and RIG1. Mol Immunol 2015; 68:194-202. [PMID: 26355912 PMCID: PMC4624043 DOI: 10.1016/j.molimm.2015.08.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 08/05/2015] [Accepted: 08/06/2015] [Indexed: 01/12/2023]
Abstract
Influenza patients frequently display increased susceptibility to Streptococcus pneumoniae co-infection and sepsis, the prevalent cause of mortality during influenza pandemics. However, the detailed mechanisms by which an influenza infection predisposes patients to suffer pneumococcal pneumonia are not fully understood. A murine model for influenza infection closely reflects the observations in human patients, since if the animals that have recovered from influenza A virus (IAV) sublethal infection are challenged with S. pneumoniae, they undergo a usually fatal uncontrolled cytokine response. We have previously demonstrated both in vitro and in vivo that the expression and secretion of galectin-1 (Gal1) and galectin-3 (Gal3) are modulated during IAV infection, and that the viral neuraminidase unmasks galactosyl moieties in the airway epithelia. In this study we demonstrate in vitro that the binding of secreted Gal1 and Gal3 to the epithelial cell surface modulates the expression of SOCS1 and RIG1, and activation of ERK, AKT or JAK/STAT1 signaling pathways, leading to a disregulated expression and release of pro-inflammatory cytokines. Our results suggest that the activity of the viral and pneumococcal neuraminidases on the surface of the airway epithelial cells function as a "danger signal" that leads to rapid upregulation of SOCS1 expression to prevent an uncontrolled inflammatory response. The binding of extracellular Gal1 or Gal3 to the galactosyl moieties unmasked on the surface of airway epithelial cells can either "fine-tune" or severely disregulate this process, respectively, the latter potentially leading to hypercytokinemia.
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Affiliation(s)
- Mihai Nita-Lazar
- Department of Microbiology and Immunology, University of Maryland School of Medicine, and Institute of Marine and Environmental Technology, Columbus Center, 701 East Pratt Street, Baltimore, MD 21202, USA
| | - Aditi Banerjee
- Department of Microbiology and Immunology, University of Maryland School of Medicine, and Institute of Marine and Environmental Technology, Columbus Center, 701 East Pratt Street, Baltimore, MD 21202, USA
| | - Chiguang Feng
- Department of Microbiology and Immunology, University of Maryland School of Medicine, and Institute of Marine and Environmental Technology, Columbus Center, 701 East Pratt Street, Baltimore, MD 21202, USA
| | - Gerardo R Vasta
- Department of Microbiology and Immunology, University of Maryland School of Medicine, and Institute of Marine and Environmental Technology, Columbus Center, 701 East Pratt Street, Baltimore, MD 21202, USA.
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Barros BCSC, Maza PK, Alcantara C, Suzuki E. Paracoccidioides brasiliensis induces recruitment of α3 and α5 integrins into epithelial cell membrane rafts, leading to cytokine secretion. Microbes Infect 2015; 18:68-77. [PMID: 26369712 DOI: 10.1016/j.micinf.2015.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 09/01/2015] [Accepted: 09/02/2015] [Indexed: 12/31/2022]
Abstract
Paracoccidioides brasiliensis is one of the etiological agents of paracoccidioidomycosis, a human systemic mycosis, highly prevalent in Latin America. In the present work, we demonstrate that P. brasiliensis yeasts promote IL-6 and IL-8 secretion by the human lung epithelial cell line A549 in an integrin-dependent manner. In fact, small interfering RNA directed to α3 and α5 integrins decreased IL-6 and IL-8 levels in P. brasiliensis-infected A549 cell cultures. This fungus also led to an increase in the expression of α3 and α5 integrins in this epithelial cell line. In addition, P. brasiliensis yeasts promoted α3 and α5 integrins clustering into A549 cell membrane rafts. Furthermore, epithelial cell membrane raft disruption with nystatin decreased IL-6 and IL-8 levels in P. brasiliensis-A549 cell cultures. Therefore, by increasing host α3 and α5 integrins levels and clustering these receptors into membrane rafts, P. brasiliensis yeasts may modulate host inflammation.
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Affiliation(s)
- Bianca C S C Barros
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Rua Botucatu, 862, 6(o) andar, São Paulo, SP, 04023-062, Brazil
| | - Paloma K Maza
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Rua Botucatu, 862, 6(o) andar, São Paulo, SP, 04023-062, Brazil
| | - Cristiane Alcantara
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Rua Botucatu, 862, 6(o) andar, São Paulo, SP, 04023-062, Brazil
| | - Erika Suzuki
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, Rua Botucatu, 862, 6(o) andar, São Paulo, SP, 04023-062, Brazil.
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Dissociation of HSV gL from gH by αvβ6- or αvβ8-integrin promotes gH activation and virus entry. Proc Natl Acad Sci U S A 2015; 112:E3901-10. [PMID: 26157134 DOI: 10.1073/pnas.1506846112] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Herpes simplex virus (HSV) is an important human pathogen. It enters cells through an orchestrated process that requires four essential glycoproteins, gD, gH/gL, and gB, activated in cascade fashion by receptor-binding and signaling. gH/gL heterodimer is conserved across the Herpesviridae family. HSV entry is enabled by gH/gL interaction with αvβ6- or αvβ8-integrin receptors. We report that the interaction of virion gH/gL with integrins resulted in gL dissociation and its release in the medium. gL dissociation occurred if all components of the entry apparatus-receptor-bound gD and gB-were present and was prevented if entry was blocked by a neutralizing monoclonal antibody to gH or by a mutation in gH. We propose that (i) gL dissociation from gH/gL is part of the activation of HSV glycoproteins, critical for HSV entry; and (ii) gL is a functional inhibitor of gH and maintains gH in an inhibited form until receptor-bound gD and integrins signal to gH/gL.
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