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Cheng R, Zhou C, Zhao M, Zhang S, Wan W, Yu Y, Wen B, Jiao J, Xiong X, Xu Q, OuYang X. TRIM56-mediated production of type I interferon inhibits intracellular replication of Rickettsia rickettsii. Microbiol Spectr 2024; 12:e0369523. [PMID: 38358243 PMCID: PMC10986528 DOI: 10.1128/spectrum.03695-23] [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: 10/17/2023] [Accepted: 01/18/2024] [Indexed: 02/16/2024] Open
Abstract
Rickettsia rickettsii (R. rickettsii), the causative agent of Rocky Mountain spotted fever (RMSF), is the most pathogenic member among Rickettsia spp. Previous studies have shown that tripartite motif-containing 56 (TRIM56) E3 ligase-induced ubiquitination of STING is important for cytosolic DNA sensing and type I interferon production to induce anti-DNA viral immunity, but whether it affects intracellular replication of R. rickettsii remains uncharacterized. Here, we investigated the effect of TRIM56 on HeLa and THP-1 cells infected with R. rickettsii. We found that the expression of TRIM56 was upregulated in the R. rickettsii-infected cells, and the overexpression of TRIM56 inhibited the intracellular replication of R. rickettsii, while R. rickettsii replication was enhanced in the TRIM56-silenced host cells with the reduced phosphorylation of IRF3 and STING and the increased production of interferon-β. In addition, the mutation of the TRIM56 E3 ligase catalytic site impairs the inhibitory function against R. rickettsii in HeLa cells. Altogether, our study discovers that TRIM56 is a host restriction factor of R. rickettsii by regulating the cGAS-STING-mediated signaling pathway. This study gives new evidence for the role of TRIM56 in the innate immune response against intracellular bacterial infection and provides new therapeutic targets for RMSF. IMPORTANCE Given that Rickettsia rickettsii (R. rickettsii) is the most pathogenic member within the Rickettsia genus and serves as the causative agent of Rocky Mountain spotted fever, there is a growing need to explore host targets. In this study, we examined the impact of host TRIM56 on R. rickettsii infection in HeLa and THP-1 cells. We observed a significant upregulation of TRIM56 expression in R. rickettsii-infected cells. Remarkably, the overexpression of TRIM56 inhibited the intracellular replication of R. rickettsii, while silencing TRIM56 enhanced bacterial replication accompanied by reduced phosphorylation of IRF3 and STING, along with increased interferon-β production. Notably, the mutation of the TRIM56's E3 ligase catalytic site did not impede R. rickettsii replication in HeLa cells. Collectively, our findings provide novel insights into the role of TRIM56 as a host restriction factor against R. rickettsii through the modulation of the cGAS-STING signaling pathway.
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Affiliation(s)
- Ruxi Cheng
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Chunyu Zhou
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Mingliang Zhao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Shan Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Weiqiang Wan
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Yonghui Yu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Bohai Wen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Jun Jiao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Xiaolu Xiong
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Qin Xu
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Xuan OuYang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
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Dahmani M, Zhu JC, Cook JH, Riley SP. Anaphylatoxin signaling activates macrophages to control intracellular Rickettsia proliferation. Microbiol Spectr 2023; 11:e0253823. [PMID: 37855623 PMCID: PMC10714731 DOI: 10.1128/spectrum.02538-23] [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: 06/20/2023] [Accepted: 09/11/2023] [Indexed: 10/20/2023] Open
Abstract
IMPORTANCE Pathogenic Rickettsia species are extremely dangerous bacteria that grow within the cytoplasm of host mammalian cells. In most cases, these bacteria are able to overpower the host cell and grow within the protected environment of the cytoplasm. However, a dramatic conflict occurs when Rickettsia encounter innate immune cells; the bacteria can "win" by taking over the host, or the bacteria can "lose" if the host cell efficiently fights the infection. This manuscript examines how the immune complement system is able to detect the presence of Rickettsia and alert nearby cells. Byproducts of complement activation called anaphylatoxins are signals that "activate" innate immune cells to mount an aggressive defensive strategy. This study enhances our collective understanding of the innate immune reaction to intracellular bacteria and will contribute to future efforts at controlling these dangerous infections.
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Affiliation(s)
- Mustapha Dahmani
- Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA
| | - Jinyi C. Zhu
- Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA
| | - Jack H. Cook
- Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA
| | - Sean P. Riley
- Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA
- Virginia-Maryland College of Veterinary Medicine, College Park, Maryland, USA
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3
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Jiang W, Wu D, Zeng Q, Liu C, Chen E, Bai L, Tang H. USP18
Attenuates the Anti-Hepatitis B Virus Effect of Ifn by Down Regulating JAK-STAT Pathway. Future Virol 2022; 17:819-828. [DOI: 10.2217/fvl-2022-0063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 09/06/2022] [Indexed: 11/21/2022]
Affiliation(s)
- Wei Jiang
- Center of Infectious Diseases
West China Hospital of Sichuan University
Chengdu
Sichuan
610041
China
| | - Dongbo Wu
- Center of Infectious Diseases
West China Hospital of Sichuan University
Chengdu
Sichuan
610041
China
| | - Qingmin Zeng
- Center of Infectious Diseases
West China Hospital of Sichuan University
Chengdu
Sichuan
610041
China
| | - Cong Liu
- Center of Infectious Diseases
West China Hospital of Sichuan University
Chengdu
Sichuan
610041
China
| | - Enqiang Chen
- Center of Infectious Diseases
West China Hospital of Sichuan University
Chengdu
Sichuan
610041
China
| | - Lang Bai
- Center of Infectious Diseases
West China Hospital of Sichuan University
Chengdu
Sichuan
610041
China
| | - Hong Tang
- Center of Infectious Diseases
West China Hospital of Sichuan University
Chengdu
Sichuan
610041
China
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4
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The diverse repertoire of ISG15: more intricate than initially thought. Exp Mol Med 2022; 54:1779-1792. [PMID: 36319753 PMCID: PMC9722776 DOI: 10.1038/s12276-022-00872-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 08/03/2022] [Accepted: 08/08/2022] [Indexed: 11/05/2022] Open
Abstract
ISG15, the product of interferon (IFN)-stimulated gene 15, is the first identified ubiquitin-like protein (UBL), which plays multifaceted roles not only as a free intracellular or extracellular molecule but also as a post-translational modifier in the process of ISG15 conjugation (ISGylation). ISG15 has only been identified in vertebrates, indicating that the functions of ISG15 and its conjugation are restricted to higher eukaryotes and have evolved with IFN signaling. Despite the highlighted complexity of ISG15 and ISGylation, it has been suggested that ISG15 and ISGylation profoundly impact a variety of cellular processes, including protein translation, autophagy, exosome secretion, cytokine secretion, cytoskeleton dynamics, DNA damage response, telomere shortening, and immune modulation, which emphasizes the necessity of reassessing ISG15 and ISGylation. However, the underlying mechanisms and molecular consequences of ISG15 and ISGylation remain poorly defined, largely due to a lack of knowledge on the ISG15 target repertoire. In this review, we provide a comprehensive overview of the mechanistic understanding and molecular consequences of ISG15 and ISGylation. We also highlight new insights into the roles of ISG15 and ISGylation not only in physiology but also in the pathogenesis of various human diseases, especially in cancer, which could contribute to therapeutic intervention in human diseases.
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Sensing the Messenger: Potential Roles of Cyclic-di-GMP in Rickettsial Pathogenesis. Int J Mol Sci 2022; 23:ijms23073853. [PMID: 35409212 PMCID: PMC8999164 DOI: 10.3390/ijms23073853] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/28/2022] [Accepted: 03/30/2022] [Indexed: 02/04/2023] Open
Abstract
Pathogenic bacteria causing human rickettsioses, transmitted in nature by arthropod vectors, primarily infect vascular endothelial cells lining the blood vessels, resulting in 'endothelial activation' and onset of innate immune responses. Nucleotide second messengers are long presumed to be the stimulators of type I interferons, of which bacterial cyclic-di-GMP (c-di-GMP) has been implicated in multiple signaling pathways governing communication with other bacteria and host cells, yet its importance in the context of rickettsial interactions with the host has not been investigated. Here, we report that all rickettsial genomes encode a putative diguanylate cyclase pleD, responsible for the synthesis of c-di-GMP. In silico analysis suggests that although the domain architecture of PleD is apparently well-conserved among different rickettsiae, the protein composition and sequences likely vary. Interestingly, cloning and sequencing of the pleD gene from virulent (Sheila Smith) and avirulent (Iowa) strains of R. rickettsii reveals a nonsynonymous substitution, resulting in an amino acid change (methionine to isoleucine) at position 236. Additionally, a previously reported 5-bp insertion in the genomic sequence coding for pleD (NCBI accession: NC_009882) was not present in the sequence of our cloned pleD from R. rickettsii strain Sheila Smith. In vitro infection of HMECs with R. rickettsii (Sheila Smith), but not R. rickettsii (Iowa), resulted in dynamic changes in the levels of pleD up to 24 h post-infection. These findings thus provide the first evidence for the potentially important role(s) of c-di-GMP in the determination of host-cell responses to pathogenic rickettsiae. Further studies into molecular mechanisms through which rickettsial c-di-GMP might regulate pathogen virulence and host responses should uncover the contributions of this versatile bacterial second messenger in disease pathogenesis and immunity to human rickettsioses.
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Wang Y, Han Y, Wang L, Zou M, Sun Y, Sun H, Guo Q, Peng X. Mycoplasma gallisepticum escapes the host immune response via gga-miR-365-3p/SOCS5/STATs axis. Vet Res 2022; 53:103. [PMID: 36471418 PMCID: PMC9721073 DOI: 10.1186/s13567-022-01117-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 08/16/2022] [Indexed: 12/09/2022] Open
Abstract
A disruption in the expression of gga-miR-365-3p was confirmed in the Mycoplasma gallisepticum (MG)-infected Chicken primary alveolar type II epithelial (CP-II) cells based on previous sequencing results, but the role it plays in the infection was unclear. In the present study, we demonstrate that MG evaded cellular host immunity via a gga-miR-365-3p/SOCS5-JAK/STATs negative feedback loop. Specifically, we found that at the initial stage of MG infection in cells, gga-miR-365-3p was rapidly increased and activated the JAK/STAT signaling pathway by inhibiting SOCS5, which induced the secretion of inflammatory factors and triggered immune response against MG infection. Over time, though, the infection progressed, MG gradually destroyed the immune defences of CP-II cells. In late stages of infection, MG escaped host immunity by reducing intracellular gga-miR-365-3p and inhibiting the JAK/STAT pathway to suppress the secretion of inflammatory factors and promote MG adhesion or invasion. These results revealed the game between MG and host cell interactions, providing a new perspective to gain insight into the pathogenic mechanisms of MG or other pathogens. Meanwhile, they also contributed to novel thoughts on the prevention and control of MG and other pathogenic infections, shedding light on the immune modulating response triggered by pathogen invasion and their molecular targeting.
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Affiliation(s)
- Yingjie Wang
- grid.35155.370000 0004 1790 4137Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Huazhong Agricultural University, Hubei 430070 Wuhan, China
| | - Yun Han
- grid.35155.370000 0004 1790 4137Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Huazhong Agricultural University, Hubei 430070 Wuhan, China
| | - Lulu Wang
- grid.35155.370000 0004 1790 4137Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Huazhong Agricultural University, Hubei 430070 Wuhan, China
| | - Mengyun Zou
- grid.35155.370000 0004 1790 4137Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Huazhong Agricultural University, Hubei 430070 Wuhan, China
| | - Yingfei Sun
- grid.35155.370000 0004 1790 4137Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Huazhong Agricultural University, Hubei 430070 Wuhan, China
| | - Huanling Sun
- grid.35155.370000 0004 1790 4137Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Huazhong Agricultural University, Hubei 430070 Wuhan, China
| | - Qiao Guo
- grid.35155.370000 0004 1790 4137Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Huazhong Agricultural University, Hubei 430070 Wuhan, China
| | - Xiuli Peng
- grid.35155.370000 0004 1790 4137Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, Huazhong Agricultural University, Hubei 430070 Wuhan, China
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Dahmani M, Cook JH, Zhu JC, Riley SP. Contribution of classical complement activation and IgM to the control of Rickettsia infection. Mol Microbiol 2021; 116:1476-1488. [PMID: 34725868 PMCID: PMC8955150 DOI: 10.1111/mmi.14839] [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: 10/05/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 01/02/2023]
Abstract
Pathogenic Rickettsia are obligate intracellular bacteria and the etiologic agents of many life‐threatening infectious diseases. Due to the serious nature of these infections, it is imperative to both identify the responsive immune sensory pathways and understand the associated immune mechanisms that restrict Rickettsia proliferation. Previous studies have demonstrated that the mammalian complement system is both activated during Rickettsia infection and contributes to the immune response to infection. To further define this component of the mammalian anti‐Rickettsia immune response, we sought to identify the mechanism(s) of complement activation during Rickettsia infection. We have employed a series of in vitro and in vivo models of infection to investigate the role of the classical complement activation pathway during Rickettsia infection. Depletion or elimination of complement activity demonstrates that both C1q and pre‐existing IgM contribute to complement activation; thus implicating the classical complement system in Rickettsia‐mediated complement activation. Elimination of the classical complement pathway from mice increases susceptibility to R. australis infection with both increased bacterial loads in multiple tissues and decreased immune activation markers. This study highlights the role of the classical complement pathway in immunity against Rickettsia and implicates resident Rickettsia‐responsive IgM in the response to infection.
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Affiliation(s)
- Mustapha Dahmani
- Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA.,Virginia-Maryland College of Veterinary Medicine, College Park, Maryland, USA
| | - Jack H Cook
- Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA.,Virginia-Maryland College of Veterinary Medicine, College Park, Maryland, USA
| | - Jinyi C Zhu
- Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA.,Virginia-Maryland College of Veterinary Medicine, College Park, Maryland, USA
| | - Sean P Riley
- Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA.,Virginia-Maryland College of Veterinary Medicine, College Park, Maryland, USA
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8
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Kang JA, Jeon YJ. Emerging Roles of USP18: From Biology to Pathophysiology. Int J Mol Sci 2020; 21:ijms21186825. [PMID: 32957626 PMCID: PMC7555095 DOI: 10.3390/ijms21186825] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/14/2020] [Accepted: 09/14/2020] [Indexed: 12/20/2022] Open
Abstract
Eukaryotic proteomes are enormously sophisticated through versatile post-translational modifications (PTMs) of proteins. A large variety of code generated via PTMs of proteins by ubiquitin (ubiquitination) and ubiquitin-like proteins (Ubls), such as interferon (IFN)-stimulated gene 15 (ISG15), small ubiquitin-related modifier (SUMO) and neural precursor cell expressed, developmentally downregulated 8 (NEDD8), not only provides distinct signals but also orchestrates a plethora of biological processes, thereby underscoring the necessity for sophisticated and fine-tuned mechanisms of code regulation. Deubiquitinases (DUBs) play a pivotal role in the disassembly of the complex code and removal of the signal. Ubiquitin-specific protease 18 (USP18), originally referred to as UBP43, is a major DUB that reverses the PTM of target proteins by ISG15 (ISGylation). Intriguingly, USP18 is a multifaceted protein that not only removes ISG15 or ubiquitin from conjugated proteins in a deconjugating activity-dependent manner but also acts as a negative modulator of type I IFN signaling, irrespective of its catalytic activity. The function of USP18 has become gradually clear, but not yet been completely addressed. In this review, we summarize recent advances in our understanding of the multifaceted roles of USP18. We also highlight new insights into how USP18 is implicated not only in physiology but also in pathogenesis of various human diseases, involving infectious diseases, neurological disorders, and cancers. Eventually, we integrate a discussion of the potential of therapeutic interventions for targeting USP18 for disease treatment.
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Affiliation(s)
- Ji An Kang
- Department of Biochemistry, Chungnam National University College of Medicine, Daejeon 35015, Korea;
- Department of Medical Science, Chungnam National University College of Medicine, Daejeon 35015, Korea
| | - Young Joo Jeon
- Department of Biochemistry, Chungnam National University College of Medicine, Daejeon 35015, Korea;
- Department of Medical Science, Chungnam National University College of Medicine, Daejeon 35015, Korea
- Correspondence: ; Tel.: +82-42-280-6766; Fax: +82-42-280-6769
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Cutaneous Immunoprofiles of Three Spotted Fever Group Rickettsia Cases. Infect Immun 2020; 88:IAI.00686-19. [PMID: 31907196 PMCID: PMC7093127 DOI: 10.1128/iai.00686-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 12/20/2019] [Indexed: 12/20/2022] Open
Abstract
Spotted fever group rickettsia (SFGR) can cause mild to fatal illness. The early interaction between the host and rickettsia in skin is largely unknown, and the pathogenesis of severe rickettsiosis remains an important topic. A surveillance of SFGR infection by PCR of blood and skin biopsy specimens followed by sequencing and immunohistochemical (IHC) detection was performed on patients with a recent tick bite between 2013 and 2016. Humoral and cutaneous immunoprofiles were evaluated in different SFGR cases by serum cytokine and chemokine detection, skin IHC staining, and transcriptome sequencing (RNA-seq). Spotted fever group rickettsia (SFGR) can cause mild to fatal illness. The early interaction between the host and rickettsia in skin is largely unknown, and the pathogenesis of severe rickettsiosis remains an important topic. A surveillance of SFGR infection by PCR of blood and skin biopsy specimens followed by sequencing and immunohistochemical (IHC) detection was performed on patients with a recent tick bite between 2013 and 2016. Humoral and cutaneous immunoprofiles were evaluated in different SFGR cases by serum cytokine and chemokine detection, skin IHC staining, and transcriptome sequencing (RNA-seq). A total of 111 SFGR cases were identified, including 79 “Candidatus Rickettsia tarasevichiae,” 22 Rickettsia raoultii, 8 Rickettsia sibirica, and 2 Rickettsia heilongjiangensis cases. The sensitivity to detect SFGR in skin biopsy specimens (9/24, 37.5%) was significantly higher than that in blood samples (105/2,671, 3.9%) (P < 0.05). As early as 1 day after the tick bite, rickettsiae could be detected in the skin. R. sibirica infection was more severe than “Ca. Rickettsia” and R. raoultii infections. Increased levels of serum interleukin-18 (IL-18), IP10, and monokine induced by gamma interferon (MIG) and decreased levels of IL-2 were observed in febrile patients infected with R. sibirica compared to those infected with “Ca. Rickettsia.” RNA-seq and IHC staining could not discriminate between SFGR-infected and uninfected tick bite skin lesions. However, the type I interferon (IFN) response was differently expressed between R. sibirica and R. raoultii infections at the cutaneous interface. It is concluded that skin biopsy specimens were more reliable for the detection of SFGR infection in human patients although the immunoprofile may be complicated by immunomodulators induced by the tick bite.
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Narra HP, Sahni A, Khanipov K, Fofanov Y, Sahni SK. Global Transcriptomic Profiling of Pulmonary Gene Expression in an Experimental Murine Model of Rickettsia conorii Infection. Genes (Basel) 2019; 10:genes10030204. [PMID: 30857242 PMCID: PMC6470625 DOI: 10.3390/genes10030204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 02/27/2019] [Accepted: 03/04/2019] [Indexed: 02/06/2023] Open
Abstract
Mediterranean spotted fever develops from an infection with Rickettsia conorii, an obligate intracellular, Gram-negative, endotheliotropic, and tick-transmitted bacterial pathogen, and is an acute, febrile illness that can progress to life-threatening complications if not diagnosed and treated early with effective antibiotics. Despite significant morbidity and mortality, little is known about changes in gene expression that determine the host responses during in vivo infection. We have investigated the transcriptional landscape of host lungs as a prominently affected organ system in an established murine model of infection by RNA-sequencing. Ingenuity pathway analysis resulted in the identification of 1332 differentially expressed genes and 292 upstream regulators. Notably, genes encoding for ubiquitin D, aconitate decarboxylase, antimicrobial peptides, calgranulins, cytokines and chemokines, and guanylate binding proteins were highly up-regulated, whereas those involved in hemoglobin biosynthesis and heme homeostasis were significantly down-regulated. Amongst response regulators, nucleotide-binding oligomerization domain-containing protein 2 and killer cell lectin-like receptors were differentially expressed, and gene clustering revealed eukaryotic initiation factor-2, oxidative phosphorylation, and ubiquitination as the predominantly activated biological pathways. Collectively, this first global transcriptomic profiling has identified R. conorii-induced regulation of novel genes and pathways in the host lungs, further in-depth investigation of which will strengthen our understanding of the pathogenesis of human rickettsioses.
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Affiliation(s)
- Hema P Narra
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Abha Sahni
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Kamil Khanipov
- Department of Pharmacology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Yuriy Fofanov
- Department of Pharmacology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Sanjeev K Sahni
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
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11
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USP18 - a multifunctional component in the interferon response. Biosci Rep 2018; 38:BSR20180250. [PMID: 30126853 PMCID: PMC6240716 DOI: 10.1042/bsr20180250] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/16/2018] [Accepted: 08/17/2018] [Indexed: 12/20/2022] Open
Abstract
Ubiquitin-specific proteases (USPs) represent the largest family of deubiquitinating enzymes (DUB). These proteases cleave the isopeptide bond between ubiquitin and a lysine residue of a ubiquitin-modified protein. USP18 is a special member of the USP family as it only deconjugates the ubiquitin-like protein ISG15 (interferon-stimulated gene (ISG) 15) from target proteins but is not active towards ubiquitin. Independent of its protease activity, USP18 functions as a major negative regulator of the type I interferon response showing that USP18 is – at least – a bifunctional protein. In this review, we summarise our current knowledge of protease-dependent and -independent functions of USP18 and discuss the structural basis of its dual activity.
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12
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Gu T, Lu L, An C, Zhang Y, Wu X, Xu Q, Chen G. Negative regulation of the RLR-mediated IFN signaling pathway by duck ubiquitin-specific protease 18 (USP18). J Cell Physiol 2018; 234:3995-4004. [PMID: 30256391 DOI: 10.1002/jcp.27208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 07/13/2018] [Indexed: 01/22/2023]
Abstract
Ubiquitin-specific protease 18 (USP18) plays an important role in regulating type I interferon (IFN) signaling in innate immunity, and has a crucial impact on the IFN therapeutic effect. Although significant progress has been made in elucidating USP18 function in mammals, the role of USP18 in ducks (duUSP18) remains poorly understood. In this study, we cloned the USP18 gene from white crested ducks by reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of complementary DNA (cDNA) ends. We determined that duUSP18 cDNA contains a 52-bp 5'UTR, a 1,131-bp open reading frame and a 356-bp 3'UTR, and encodes a 376-amino acid protein. Multiple sequence alignments showed that duUSP18 shares high similarity with USP18 from other vertebrates. Overexpression of duUSP18 inhibited nuclear factor-κB (NF-κB) and interferon regulatory factor 1 (IRF1) activity, and reduced IFN-β production following 5' triphosphate double-stranded RNA (5'ppp dsRNA) or lipopolysaccharide (LPS) stimulation. duUSP18 knockdown significantly activated 5'ppp dsRNA-induced and LPS-induced NF-κB and IRF1 activation, and induced IFN-β expression in duck embryo fibroblasts. Furthermore, Quantitative real-time PCR (qRT-PCR) revealed that overexpression or knockdown of duUSP18 could alter the expression of genes related to the RLR-mediated IFN signaling pathway following the treatment with 5'ppp dsRNA. In addition, site-directed mutation analysis revealed that cysteine 66 (C66), histidine 313 (H313), and histidine 321 (H321) of duUSP18 were critical for inhibiting IFN-β activity. Taken together, these results suggest that duck USP18 plays an important role in innate immune responses against double-stranded RNA viruses in the RLR-mediated IFN signaling pathway, and that further studies are warranted to elucidate its underlying mechanisms, which could provide molecular insights into the effect of the treatment of duck diseases.
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Affiliation(s)
- Tiantian Gu
- Key Laboratory of Animal Genetics, Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, China
| | - Lu Lu
- Key Laboratory of Animal Genetics, Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, China
| | - Chen An
- Key Laboratory of Animal Genetics, Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, China
| | - Yu Zhang
- Key Laboratory of Animal Genetics, Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, China
| | - Xinsheng Wu
- Key Laboratory of Animal Genetics, Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, China
| | - Qi Xu
- Key Laboratory of Animal Genetics, Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, China
| | - Guohong Chen
- Key Laboratory of Animal Genetics, Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, China
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13
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Sahni A, Fang R, Sahni SK, Walker DH. Pathogenesis of Rickettsial Diseases: Pathogenic and Immune Mechanisms of an Endotheliotropic Infection. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2018; 14:127-152. [PMID: 30148688 DOI: 10.1146/annurev-pathmechdis-012418-012800] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Obligately intracytosolic rickettsiae that cycle between arthropod and vertebrate hosts cause human diseases with a spectrum of severity, primarily by targeting microvascular endothelial cells, resulting in endothelial dysfunction. Endothelial cells and mononuclear phagocytes have important roles in the intracellular killing of rickettsiae upon activation by the effector molecules of innate and adaptive immunity. In overwhelming infection, immunosuppressive effects contribute to the severity of illness. Rickettsia-host cell interactions involve host cell receptors for rickettsial ligands that mediate cell adhesion and, in some instances, trigger induced phagocytosis. Rickettsiae interact with host cell actin to effect both cellular entry and intracellular actin-based mobility. The interaction of rickettsiae with the host cell also involves rickettsial evasion of host defense mechanisms and exploitation of the intracellular environment. Signal transduction events exemplify these effects. An intriguing frontier is the array of rickettsial noncoding RNA molecules and their potential effects on the pathogenesis and transmission of rickettsial diseases.
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Affiliation(s)
- Abha Sahni
- The University of Texas Medical Branch at Galveston, Galveston, Texas 77555-0609, USA; , , ,
| | - Rong Fang
- The University of Texas Medical Branch at Galveston, Galveston, Texas 77555-0609, USA; , , ,
| | - Sanjeev K Sahni
- The University of Texas Medical Branch at Galveston, Galveston, Texas 77555-0609, USA; , , ,
| | - David H Walker
- The University of Texas Medical Branch at Galveston, Galveston, Texas 77555-0609, USA; , , ,
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14
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Zeng M, Chen S, Zhang J, Wu Z, Wang M, Jia R, Zhu D, Liu M, Sun K, Yang Q, Wu Y, Zhao X, Cheng A. Molecular identification of goose (Anser cygnoide) suppressor ubiquitin-specific protease 18 (USP18) and the effects of goose IFN and TMUV on its comparative transcripts. Poult Sci 2018; 97:1022-1031. [PMID: 29267974 DOI: 10.3382/ps/pex322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 10/11/2017] [Indexed: 11/20/2022] Open
Abstract
Ubiquitin-specific protease 18 (USP18) is known as an inhibition factor and has been associated with the innate immune response to pathogens. USP18 is the only deconjugating protease with specificity for interferon-stimulated gene 15 (ISG15), which is supposed to be missing in birds. To analyze the efficacy of goose USP18 (goUSP18) against Tembusu virus (TMUV) infection, we first cloned USP18 homologous cDNA from TMUV infected geese. The coding sequence was 1131 bp, and the deduced amino acid sequence shared conserved motifs with its homologues. Tissue-specific expression has shown that goUSP18 transcripts are strongly expressed in the spleen and liver of adult geese, as well as in the pancreas of goslings. Moreover, the goUSP18 transcripts were induced by goose interferons (goIFN) in goose embryo fibroblasts (GEF) and by TLR ligands in peripheral blood mononuclear cells (PBMC). Notably, goUSP18 transcripts were highly up-regulated by TMUV infection compared to the basal level in uninfected birds. Taken together, these results suggested that goUSP18 was involved in host innate immunity against TMUV infection.
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Affiliation(s)
- M Zeng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - S Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - J Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Z Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - M Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - R Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - D Zhu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - M Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - K Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Q Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Y Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - X Zhao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - A Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
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15
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Duncan SA, Baganizi DR, Sahu R, Singh SR, Dennis VA. SOCS Proteins as Regulators of Inflammatory Responses Induced by Bacterial Infections: A Review. Front Microbiol 2017; 8:2431. [PMID: 29312162 PMCID: PMC5733031 DOI: 10.3389/fmicb.2017.02431] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 11/23/2017] [Indexed: 12/31/2022] Open
Abstract
Severe bacterial infections can lead to both acute and chronic inflammatory conditions. Innate immunity is the first defense mechanism employed against invading bacterial pathogens through the recognition of conserved molecular patterns on bacteria by pattern recognition receptors (PRRs), especially the toll-like receptors (TLRs). TLRs recognize distinct pathogen-associated molecular patterns (PAMPs) that play a critical role in innate immune responses by inducing the expression of several inflammatory genes. Thus, activation of immune cells is regulated by cytokines that use the Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway and microbial recognition by TLRs. This system is tightly controlled by various endogenous molecules to allow for an appropriately regulated and safe host immune response to infections. Suppressor of cytokine signaling (SOCS) family of proteins is one of the central regulators of microbial pathogen-induced signaling of cytokines, principally through the inhibition of the activation of JAK/STAT signaling cascades. This review provides recent knowledge regarding the role of SOCS proteins during bacterial infections, with an emphasis on the mechanisms involved in their induction and regulation of antibacterial immune responses. Furthermore, the implication of SOCS proteins in diverse processes of bacteria to escape host defenses and in the outcome of bacterial infections are discussed, as well as the possibilities offered by these proteins for future targeted antimicrobial therapies.
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Affiliation(s)
- Skyla A Duncan
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Dieudonné R Baganizi
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Rajnish Sahu
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Shree R Singh
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
| | - Vida A Dennis
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, United States
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16
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Honke N, Shaabani N, Zhang DE, Hardt C, Lang KS. Multiple functions of USP18. Cell Death Dis 2016; 7:e2444. [PMID: 27809302 PMCID: PMC5260889 DOI: 10.1038/cddis.2016.326] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/12/2016] [Accepted: 09/16/2016] [Indexed: 12/12/2022]
Abstract
Since the discovery of the ubiquitin system and the description of its important role in the degradation of proteins, many studies have shown the importance of ubiquitin-specific peptidases (USPs). One special member of this family is the USP18 protein (formerly UBP43). In the past two decades, several functions of USP18 have been discovered: this protein is not only an isopeptidase but also a potent inhibitor of interferon signaling. Therefore, USP18 functions as 'a' maestro of many biological pathways in various cell types. This review outlines multiple functions of USP18 in the regulation of various immunological processes, including pathogen control, cancer development, and autoimmune diseases.
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Affiliation(s)
- Nadine Honke
- Institute of Immunology, Medical Faculty, University of Duisburg-Essen, Hufelandstr. 55, Essen 45147, Germany
| | - Namir Shaabani
- Institute of Immunology, Medical Faculty, University of Duisburg-Essen, Hufelandstr. 55, Essen 45147, Germany.,Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Dong-Er Zhang
- Moores UCSD Cancer Center, University of California San Diego, La Jolla, CA 92093, USA
| | - Cornelia Hardt
- Institute of Immunology, Medical Faculty, University of Duisburg-Essen, Hufelandstr. 55, Essen 45147, Germany
| | - Karl S Lang
- Institute of Immunology, Medical Faculty, University of Duisburg-Essen, Hufelandstr. 55, Essen 45147, Germany
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17
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Zhao Y, Valbuena G, Walker DH, Gazi M, Hidalgo M, DeSousa R, Oteo JA, Goez Y, Brasier AR. Endothelial Cell Proteomic Response to Rickettsia conorii Infection Reveals Activation of the Janus Kinase (JAK)-Signal Transducer and Activator of Transcription (STAT)-Inferferon Stimulated Gene (ISG)15 Pathway and Reprogramming Plasma Membrane Integrin/Cadherin Signaling. Mol Cell Proteomics 2015; 15:289-304. [PMID: 26560068 DOI: 10.1074/mcp.m115.054361] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Indexed: 11/06/2022] Open
Abstract
Rickettsia conorii is the etiologic agent of Mediterranean spotted fever, a re-emerging infectious disease with significant mortality. This Gram-negative, obligately intracellular pathogen is transmitted via tick bites, resulting in disseminated vascular endothelial cell infection with vascular leakage. In the infected human, Rickettsia conorii infects endothelial cells, stimulating expression of cytokines and pro-coagulant factors. However, the integrated proteomic response of human endothelial cells to R. conorii infection is not known. In this study, we performed quantitative proteomic profiling of primary human umbilical vein endothelial cells (HUVECs) with established R conorii infection versus those stimulated with endotoxin (LPS) alone. We observed differential expression of 55 proteins in HUVEC whole cell lysates. Of these, we observed induction of signal transducer and activator of transcription (STAT)1, MX dynamin-like GTPase (MX1), and ISG15 ubiquitin-like modifier, indicating activation of the JAK-STAT signaling pathway occurs in R. conorii-infected HUVECs. The down-regulated proteins included those involved in the pyrimidine and arginine biosynthetic pathways. A highly specific biotinylated cross-linking enrichment protocol was performed to identify dysregulation of 11 integral plasma membrane proteins that included up-regulated expression of a sodium/potassium transporter and down-regulation of α-actin 1. Analysis of Golgi and soluble Golgi fractions identified up-regulated proteins involved in platelet-endothelial adhesion, phospholipase activity, and IFN activity. Thirty four rickettsial proteins were identified with high confidence in the Golgi, plasma membrane, or secreted protein fractions. The host proteins associated with rickettsial infections indicate activation of interferon-STAT signaling pathways; the disruption of cellular adhesion and alteration of antigen presentation pathways in response to rickettsial infections are distinct from those produced by nonspecific LPS stimulation. These patterns of differentially expressed proteins suggest mechanisms of pathogenesis as well as methods for diagnosis and monitoring Rickettsia infections.
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Affiliation(s)
- Yingxin Zhao
- From the Departments of ‡Internal Medicine and §Institute for Translational Sciences, and ¶Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas 77555-1060
| | | | | | | | - Marylin Hidalgo
- the **Microbiology Department, Faculty of Sciences, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Rita DeSousa
- the ‡‡Centre for the Study of Vectors and Infectious Diseases Dr. Francisco Cambournac, National Institute of Health Dr. Ricardo Jorge, Águas de Moura, Av. Padre Cruz, Lisbon, 1649-016, Portugal, and
| | - Jose Antonio Oteo
- the §§Centre of Rickettsiosis and Arthropod-Borne Diseases, Hospital San Pedro-Centro de Investigation Biomedical de la Rioja (CIBIR), Logroño, La Rioja, 26006, Spain
| | | | - Allan R Brasier
- From the Departments of ‡Internal Medicine and §Institute for Translational Sciences, and ¶Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas 77555-1060,
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18
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Sahni SK, Narra HP, Sahni A, Walker DH. Recent molecular insights into rickettsial pathogenesis and immunity. Future Microbiol 2014; 8:1265-88. [PMID: 24059918 DOI: 10.2217/fmb.13.102] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Human infections with arthropod-borne Rickettsia species remain a major global health issue, causing significant morbidity and mortality. Epidemic typhus due to Rickettsia prowazekii has an established reputation as the 'scourge of armies', and as a major determinant of significant 'historical turning points'. No suitable vaccines for human use are currently available to prevent rickettsial diseases. The unique lifestyle features of rickettsiae include obligate intracellular parasitism, intracytoplasmic niche within the host cell, predilection for infection of microvascular endothelium in mammalian hosts, association with arthropods and the tendency for genomic reduction. The fundamental research in the field of Rickettsiology has witnessed significant recent progress in the areas of pathogen adhesion/invasion and host immune responses, as well as the genomics, proteomics, metabolomics, phylogenetics, motility and molecular manipulation of important rickettsial pathogens. The focus of this review article is to capture a snapshot of the latest developments pertaining to the mechanisms of rickettsial pathogenesis and immunity.
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Affiliation(s)
- Sanjeev K Sahni
- Department of Pathology & Institute for Human Infections & Immunity, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555, USA
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19
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Wu X, Fan J, Ouyang Z, Ning R, Guo W, Shen Y, Wu X, Sun Y, Xu Q. Tupistra chinensis extract attenuates murine fulminant hepatitis with multiple targets against activated T lymphocytes. ACTA ACUST UNITED AC 2013; 66:453-65. [PMID: 24206350 DOI: 10.1111/jphp.12176] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 10/10/2013] [Indexed: 12/31/2022]
Abstract
OBJECTIVES The extract of Tupistra chinensis (TCE) is traditionally used for the treatment of inflammatory diseases in southwestern China for hundreds of years. The present study was designed to investigate the effects of the TCE against experimental hepatitis and to illustrate its potential mechanisms. METHODS Effects of TCE were investigated on Con A-induced hepatitis. Profiles of multiple cytokines were measured with biometric immuno-sandwich ELISA. Proliferation, activation and apoptosis of T lymphocytes were evaluated using Western blot, MTT analysis and flow cytometry. KEY FINDINGS TCE significantly inhibited levels of serum transaminases and lactic dehydrogenase in mice with Con A-induced hepatitis, accompanied with marked alleviation of the liver microscopic appearances. Moreover, it decreased levels of inflammatory cytokines in a concentration-dependent manner both in vivo and in vitro. It also suppressed mitogen-activated protein kinases and NF-κB-signalling in liver. These effects of TCE are attributed to its inhibition on activated T cells but not to hepatocytes protection. Flow cytometry and immunoblot assay data showed its effects on STAT1/NF-κB-signalling blockage and apoptosis induction in activated T cells. CONCLUSION Our findings illustrate the significant potential of TCE as a novel approach for treatment of T cell-mediated inflammatory diseases.
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Affiliation(s)
- Xuefeng Wu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
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