1
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Bowman KA, Kaplonek P, McNamara RP. Understanding Fc function for rational vaccine design against pathogens. mBio 2024; 15:e0303623. [PMID: 38112418 PMCID: PMC10790774 DOI: 10.1128/mbio.03036-23] [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] [Indexed: 12/21/2023] Open
Abstract
Antibodies represent the primary correlate of immunity following most clinically approved vaccines. However, their mechanisms of action vary from pathogen to pathogen, ranging from neutralization, to opsonophagocytosis, to cytotoxicity. Antibody functions are regulated both by antigen specificity (Fab domain) and by the interaction of their Fc domain with distinct types of Fc receptors (FcRs) present in immune cells. Increasing evidence highlights the critical nature of Fc:FcR interactions in controlling pathogen spread and limiting the disease state. Moreover, variation in Fc-receptor engagement during the course of infection has been demonstrated across a range of pathogens, and this can be further influenced by prior exposure(s)/immunizations, age, pregnancy, and underlying health conditions. Fc:FcR functional variation occurs at the level of antibody isotype and subclass selection as well as post-translational modification of antibodies that shape Fc:FcR-interactions. These factors collectively support a model whereby the immune system actively harnesses and directs Fc:FcR interactions to fight disease. By defining the precise humoral mechanisms that control infections, as well as understanding how these functions can be actively tuned, it may be possible to open new paths for improving existing or novel vaccines.
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Affiliation(s)
- Kathryn A. Bowman
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
- Division of Infectious Diseases, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Paulina Kaplonek
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
| | - Ryan P. McNamara
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts, USA
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2
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Bharti R, Dey G, Lin F, Lathia J, Reizes O. CD55 in cancer: Complementing functions in a non-canonical manner. Cancer Lett 2022; 551:215935. [PMID: 36216147 PMCID: PMC11019835 DOI: 10.1016/j.canlet.2022.215935] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 09/28/2022] [Accepted: 09/29/2022] [Indexed: 11/02/2022]
Abstract
CD55, or decay accelerating factor, is a membrane lipid microdomain-associated, GPI-anchored protein implicated in the shielding of cells from complement-mediated attack via accelerating decay of C3 and C5. Loss of CD55 is associated with a number of pathologies due to hyperactivation of the complement system. CD55 is also implicated in cancer progression thought to be driven via its role in cell shielding mechanisms. We now appreciate that CD55 can signal intracellularly to promote malignant transformation, cancer progression, cell survival, angiogenesis, and inhibition of apoptosis. Outside-in signaling via CD55 is mediated by signaling pathways including JNK, JAK/STAT, MAPK/NF-κB, and LCK. Moreover, CD55 is enriched in the cancer stem cell (CSC) niche of multiple tumors including breast, ovarian, cervical, and can be induced by chemotherapeutics and hypoxic environments. CSCs are implicated in tumor recurrence and chemoresistance. Here, we review the unexpected roles of CD55 in cancer including the roles of canonical and noncanonical pathways that CD55 orchestrates. We will highlight opportunities for therapeutic targeting CD55 and gaps in the field that require more in-depth mechanistic insights.
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Affiliation(s)
- Rashmi Bharti
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Goutam Dey
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Feng Lin
- Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Justin Lathia
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Case Comprehensive Cancer Center, Cleveland, OH, USA
| | - Ofer Reizes
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Case Comprehensive Cancer Center, Cleveland, OH, USA.
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3
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Luo S, Chen Y, Yang L, Gong X, Wu Z. The complement system in retinal detachment with choroidal detachment. Curr Eye Res 2022; 47:809-812. [PMID: 35176953 DOI: 10.1080/02713683.2022.2038634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
PURPOSE This study aims to explore the differences in the levels of complement components and complement regulatory factors in the vitreous humor of patients with retinal detachment with choroidal detachment (RRDCD), patients with rhegmatogenous retinal detachment (RRD). METHODS A prospective case-control study design was used to recruit 20 patients with RRDCD and 20 patients with RRD in consecutive cases who underwent pars plana vitrectomy from March 2019 to January 2020. The control group comprised 15 patients with epiretinal membrane and 5 eyes from cadavers. The concentrations of complement C2, complement C4b, complement C5/C5a, complement C9, complement factor D (CFD), lectin, and complement factor I (CFI) were measured using Multiplex Luminex Assay, and the concentration of soluble decay acceleration factor (sDAF) was measured using ELISA. RESULTS As compared with the RRD and control groups, complement C2, complement C4b, complement C5/C5a, complement C9, CFD, lectin, CFI, and sDAF were significantly increased in the RRDCD group. Additionally, as compared with the control group, the concentrations of complement component C2 and CFD were significantly increased in the vitreous humor of the RRD group. CONCLUSION Components of all three complement pathways were elevated in eyes with RRDCD. Interestingly, while there was evidence of early complement activation in RRD, the final common pathway components were not elevated. In contrast, RRDCD eyes showed significant elevations of the MAC complex components, underscoring a potential pathophysiologic impact of complement activation in this condition.
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Affiliation(s)
- Shasha Luo
- Department of Ophthalmology, Nanjing Medical University Affiliated Wuxi Second Hospital, Wuxi, Jiangsu Province, People's Republic of China.,Department of Ophthalmology, Affiliated Wuxi Clinical College of Nantong University, Wuxi, Jiangsu Province, People's Republic of China
| | - Yanghao Chen
- Department of Ophthalmology, Anqing No.2 People's Hospital, Anqing, Anhui Province, People's Republic of China
| | - Lufei Yang
- Department of Ophthalmology, Nanjing Medical University Affiliated Wuxi Second Hospital, Wuxi, Jiangsu Province, People's Republic of China
| | - Xuechun Gong
- Department of Ophthalmology, Nanjing Medical University Affiliated Wuxi Second Hospital, Wuxi, Jiangsu Province, People's Republic of China
| | - Zhifeng Wu
- Department of Ophthalmology, Nanjing Medical University Affiliated Wuxi Second Hospital, Wuxi, Jiangsu Province, People's Republic of China.,Department of Ophthalmology, Affiliated Wuxi Clinical College of Nantong University, Wuxi, Jiangsu Province, People's Republic of China
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4
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Wang C, Jie J, Li D, Liu Y, Gao J, Song L. Clinical value of CD97 and CD55 levels in the differential diagnosis of tuberculous and malignant pleural effusions. Medicine (Baltimore) 2021; 100:e26771. [PMID: 34397724 PMCID: PMC8322496 DOI: 10.1097/md.0000000000026771] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 07/05/2021] [Indexed: 01/04/2023] Open
Abstract
This study evaluated the clinical levels of CD97 and CD55 for the differential diagnosis of pleural effusion.Pleural effusion samples were collected from 106 patients (55 tuberculous pleural effusions [TPE] and 51 malignant pleural effusions [MPE]). CD97 and CD55 levels in pleural effusions were measured by enzyme-linked immunosorbent assay.CD97 levels were significantly higher in the TPE group than in the MPE group (P < .001), while CD55 levels in the MPE group were significantly higher than the TPE group (P < .001). The sensitivity and specificity of CD97 testing for the differential diagnosis of TPE and MPE was 80.0% and 60.8%, respectively, while the sensitivity and specificity of CD55 testing for TPE and MPE was 88.2% and 85.5%, respectively. Furthermore, the sensitivity and specificity of combinatorial CD97 and CD55 testing for TPE and MPE was 90.0% and 87.5%, respectively. Moreover, CD97 and CD55 were negatively correlated in the MPE group (r = -0.383, P = .005), while no correlations were observed in the TPE group. CD97 or CD55 showed no correlations with other inflammatory cytokines (tumor necrosis factor α, interleukin 1β, erythrocyte sedimentation rate, and C-reactive protein) in both groups (P > .05).CD97 and CD55 may be used as biological markers for the differential diagnosis of pleural effusion in clinical settings.
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Affiliation(s)
- Chunyan Wang
- Cadre's Wards, Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Jing Jie
- Department of Respiratory Medicine, Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Dan Li
- Department of Respiratory Medicine, Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Ying Liu
- Department of Respiratory Medicine, Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Jinying Gao
- Department of Respiratory Medicine, Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, First Hospital of Jilin University, Changchun, Jilin Province, China
| | - Lei Song
- Department of Respiratory Medicine, Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, First Hospital of Jilin University, Changchun, Jilin Province, China
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5
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Jang KO, Lee YW, Kim H, Chung DK. Complement Inactivation Strategy of Staphylococcus aureus Using Decay-Accelerating Factor and the Response of Infected HaCaT Cells. Int J Mol Sci 2021; 22:4015. [PMID: 33924622 PMCID: PMC8070078 DOI: 10.3390/ijms22084015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/09/2021] [Accepted: 04/10/2021] [Indexed: 12/23/2022] Open
Abstract
Staphylococcus aureus is a species of Gram-positive staphylococcus. It can cause sinusitis, respiratory infections, skin infections, and food poisoning. Recently, it was discovered that S. aureus infects epithelial cells, but the interaction between S. aureus and the host is not well known. In this study, we confirmed S. aureus to be internalized by HaCaT cells using the ESAT-6-like protein EsxB and amplified within the host over time by escaping host immunity. S. aureus increases the expression of decay-accelerating factor (CD55) on the surfaces of host cells, which inhibits the activation of the complement system. This mechanism makes it possible for S. aureus to survive in host cells. S. aureus, sufficiently amplified within the host, is released through the initiation of cell death. On the other hand, the infected host cells increase their surface expression of UL16 binding protein 1 to inform immune cells that they are infected and try to be eliminated. These host defense systems seem to involve the alteration of tight junctions and the induction of ligand expression to activate immune cells. Taken together, our study elucidates a novel aspect of the mechanisms of infection and immune system evasion for S. aureus.
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Affiliation(s)
- Kyoung Ok Jang
- Graduate School of Biotechnology, Kyung Hee University, Yongin 17104, Korea; (K.O.J.); (Y.W.L.)
| | - Youn Woo Lee
- Graduate School of Biotechnology, Kyung Hee University, Yongin 17104, Korea; (K.O.J.); (Y.W.L.)
| | - Hangeun Kim
- Research and Development Center, Skin Biotechnology Center Inc., Yongin 17104, Korea
| | - Dae Kyun Chung
- Graduate School of Biotechnology, Kyung Hee University, Yongin 17104, Korea; (K.O.J.); (Y.W.L.)
- Research and Development Center, Skin Biotechnology Center Inc., Yongin 17104, Korea
- Skin Biotechnology Center, Kyung Hee University, Suwon 16229, Korea
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6
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Li M, Li YP, Deng HL, Wang MQ, Wang WJ, Wang J, Wu FP, Dang SS. Association of gene polymorphisms of CD55 with susceptibility to and severity of hand, foot, and mouth disease caused by enterovirus 71 in the Han Chinese population. J Med Virol 2020; 92:3119-3124. [PMID: 32470169 DOI: 10.1002/jmv.26088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 05/23/2020] [Indexed: 12/13/2022]
Abstract
Hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) can lead to high morbidity and mortality, and genetic background plays an important role during the disease process. We investigated the association between the single-nucleotide polymorphism (SNP) rs2564978 of the CD55 gene and susceptibility to and severity of HFMD using the SNPs can multiple SNP typing methods. Soluble CD55 (sCD55) expression was significantly lower in the EV71 HFMD group than in the control group and lower in severe cases than in mild cases (P < .001). Moreover, CD55 rs2564978 (C vs T OR = 1.300, 95% CI, 1.120-1.509) was associated with the risk of EV71 infection, and genotype TC was related to the severity of the infection (TC vs TT OR = 4.523, 95% CI, 2.033-10.066). Our results suggest that sCD55 expression and the CD55 polymorphism rs2564978 may influence the susceptibility to and severity of EV71 infection.
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Affiliation(s)
- Mei Li
- Department of Infectious Diseases, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Ya-Ping Li
- Department of Infectious Diseases, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Hui-Ling Deng
- Department of Infectious Diseases, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
- Department of Infectious Diseases, Xi'an Children's Hospital, Xi'an, China
| | - Mu-Qi Wang
- Department of Infectious Diseases, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Wen-Jun Wang
- Department of Infectious Diseases, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Jun Wang
- Department of Infectious Diseases, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
- Department of Infectious Diseases, Xi'an Children's Hospital, Xi'an, China
| | - Feng-Ping Wu
- Department of Infectious Diseases, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Shuang-Suo Dang
- Department of Infectious Diseases, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
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7
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Abstract
Liver cancer is a global problem and hepatocellular carcinoma (HCC) accounts for about 85% of this cancer. In the USA, etiologies and risk factors for HCC include chronic hepatitis C virus (HCV) infection, diabetes, non-alcoholic steatohepatitis (NASH), obesity, excessive alcohol drinking, exposure to tobacco smoke, and genetic factors. Chronic HCV infection appears to be associated with about 30% of HCC. Chronic HCV infection induces multistep changes in liver, involving metabolic disorders, steatosis, cirrhosis and HCC. Liver carcinogenesis requires initiation of neoplastic clones, and progression to clinically diagnose malignancy. Tumor progression associates with profound exhaustion of tumor-antigen-specific CD8+T cells, and accumulation of PD-1hi CD8+T cells and Tregs. In this chapter, we provide a brief description of HCV and environmental/genetic factors, immune regulation, and highlight mechanisms of HCV associated HCC. We also underscore HCV treatment and recent paradigm of HCC progression, highlighted the current treatment and potential future therapeutic opportunities.
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8
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Kumar NA, Kunnakkadan U, Thomas S, Johnson JB. In the Crosshairs: RNA Viruses OR Complement? Front Immunol 2020; 11:573583. [PMID: 33133089 PMCID: PMC7550403 DOI: 10.3389/fimmu.2020.573583] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/24/2020] [Indexed: 12/02/2022] Open
Abstract
Complement, a part of the innate arm of the immune system, is integral to the frontline defense of the host against innumerable pathogens, which includes RNA viruses. Among the major groups of viruses, RNA viruses contribute significantly to the global mortality and morbidity index associated with viral infection. Despite multiple routes of entry adopted by these viruses, facing complement is inevitable. The initial interaction with complement and the nature of this interaction play an important role in determining host resistance versus susceptibility to the viral infection. Many RNA viruses are potent activators of complement, often resulting in virus neutralization. Yet, another facet of virus-induced activation is the exacerbation in pathogenesis contributing to the overall morbidity. The severity in disease and death associated with RNA virus infections shows a tip in the scale favoring viruses. Growing evidence suggest that like their DNA counterparts, RNA viruses have co-evolved to master ingenious strategies to remarkably restrict complement. Modulation of host genes involved in antiviral responses contributed prominently to the adoption of unique strategies to keep complement at bay, which included either down regulation of activation components (C3, C4) or up regulation of complement regulatory proteins. All this hints at a possible “hijacking” of the cross-talk mechanism of the host immune system. Enveloped RNA viruses have a selective advantage of not only modulating the host responses but also recruiting membrane-associated regulators of complement activation (RCAs). This review aims to highlight the significant progress in the understanding of RNA virus–complement interactions.
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Affiliation(s)
- Nisha Asok Kumar
- Viral Disease Biology, Department of Pathogen Biology, Rajiv Gandhi Center for Biotechnology, Thiruvananthapuram, India.,Manipal Academy of Higher Education, Manipal, India
| | - Umerali Kunnakkadan
- Viral Disease Biology, Department of Pathogen Biology, Rajiv Gandhi Center for Biotechnology, Thiruvananthapuram, India.,Department of Biotechnology, University of Kerala, Thiruvananthapuram, India
| | - Sabu Thomas
- Cholera and Biofilm Research Lab, Department of Pathogen Biology, Rajiv Gandhi Center for Biotechnology, Thiruvananthapuram, India
| | - John Bernet Johnson
- Viral Disease Biology, Department of Pathogen Biology, Rajiv Gandhi Center for Biotechnology, Thiruvananthapuram, India
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9
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Abstract
A prominent role for complement has been identified in the linkage of innate and adaptive immunity. The liver is the main source of complement and hepatocytes are the primary sites for synthesis of complement components in vivo. We have discovered that hepatitis C virus (HCV) impairs C4 and C3 synthesis. Liver damage may diminish capacity of complement synthesis in patients. However, we observed that the changes in measured complement components in chronically HCV infected patients do not correlate with liver fibrosis or rheumatoid factor present in the blood, serum albumin, or alkaline phosphatase levels. Complement component C3 is of critical importance in B cell activation and T cell-dependent antibody responses. C3 activity is required for optimal expansion of CD8+T cells during a systemic viral infection. Deficiencies in complement may predispose patients to infections via ineffective opsonization, and defects in lytic activity via membrane attack complex. Interestingly, C9 is significantly reduced at the mRNA level in chronically HCV infected liver biopsy specimens, while many hepatocyte derived complement components (C6, C8, Factor B, MASP1, and MBL) and unrelated genes remain mostly unaffected. This implies an HCV specific effect, not a global effect from liver disease.
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Affiliation(s)
- Young-Chan Kwon
- Department of Internal Medicine, Saint Louis University, St. Louis, MO, USA
- Department of Molecular Microbiology and Immunology, Saint Louis University, St. Louis, MO, USA
- Institut Pasteur Korea, Daejeon, Republic of Korea
| | - Ranjit Ray
- Department of Internal Medicine, Saint Louis University, St. Louis, MO, USA.
- Department of Molecular Microbiology and Immunology, Saint Louis University, St. Louis, MO, USA.
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10
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Patra T, Ray RB, Ray R. Strategies to Circumvent Host Innate Immune Response by Hepatitis C Virus. Cells 2019; 8:E274. [PMID: 30909456 PMCID: PMC6468774 DOI: 10.3390/cells8030274] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 03/15/2019] [Accepted: 03/18/2019] [Indexed: 12/13/2022] Open
Abstract
Innate immune responses generate interferons, proinflammatory cytokines, complement activation, and natural killer (NK) cell response. Ultimately, this leads to the induction of a robust virus-specific adaptive immunity. Although the host innate immune system senses and responds to eliminate virus infection, hepatitis C virus (HCV) evades immune attack and establishes persistent infection within the liver. Spontaneous clearance of HCV infection is associated with a prompt induction of innate immunity generated in an infected host. In this review, we have highlighted the current knowledge of our understanding of host⁻HCV interactions, especially for endogenous interferon production, proinflammatory response, NK cell response, and complement activation, which may impair the generation of a strong adaptive immune response for establishment of chronicity. The information may provide novel strategies in augmenting therapeutic intervention against HCV.
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Affiliation(s)
- Tapas Patra
- Departments of Internal Medicine, Saint Louis University, St. Louis, MO 63104, USA.
| | - Ratna B Ray
- Departments of Pathology, Saint Louis University, St. Louis, MO 63104, USA.
| | - Ranjit Ray
- Departments of Internal Medicine, Saint Louis University, St. Louis, MO 63104, USA.
- Molecular Microbiology & Immunology, Saint Louis University, St. Louis, MO 63104, USA.
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11
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Ray RB, Ray R. Hepatitis C Virus Manipulates Humans as its Favorite Host for a Long-Term Relationship. Hepatology 2019; 69:889-900. [PMID: 30102776 PMCID: PMC6351149 DOI: 10.1002/hep.30214] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/07/2018] [Indexed: 02/06/2023]
Abstract
Chronic hepatitis C virus (HCV) infection-associated liver disease is a global health problem. HCV often causes silent disease, and eventually progresses to end-stage liver disease. HCV infects hepatocytes; however, initial manifestation of liver disease is mostly displayed in hepatic stellate cells (HSCs), causing fibrosis/cirrhosis, and is believed to occur from inflammation in the liver. It remains unclear why HCV is not spontaneously cleared from infected liver in the majority of individuals and develops chronic infection with progressive liver disease. Direct-acting antivirals (DAAs) show excellent results in controlling viremia, although beneficial consequence in advanced liver disease remains to be understood. In this review, we highlight the current knowledge that has contributed to our understanding of the role of HCV in inflammation, immune evasion, metabolic disorders, liver pathogeneses, and efforts in vaccine development.
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Affiliation(s)
- Ratna B. Ray
- Department of Pathology, Saint Louis University, Saint Louis, Missouri 63104, USA,Department of Internal Medicine, Saint Louis University, Saint Louis, Missouri 63104, USA
| | - Ranjit Ray
- Department of Internal Medicine, Saint Louis University, Saint Louis, Missouri 63104, USA
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12
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Dho SH, Lim JC, Kim LK. Beyond the Role of CD55 as a Complement Component. Immune Netw 2018; 18:e11. [PMID: 29503741 PMCID: PMC5833118 DOI: 10.4110/in.2018.18.e11] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 02/09/2018] [Accepted: 02/11/2018] [Indexed: 01/28/2023] Open
Abstract
The complement is a part of the immune system that plays several roles in removing pathogens. Despite the importance of the complement system, the exact role of each component has been overlooked because the complement system was thought to be a nonspecific humoral immune mechanism that worked against pathogens. Decay-accelerating factor (DAF or CD55) is a known inhibitor of the complement system and has recently attracted substantial attention due to its role in various diseases, such as cancer, protein-losing enteropathy, and malaria. Some protein-losing enteropathy cases are caused by CD55 deficiency, which leads to complement hyperactivation, malabsorption, and angiopathic thrombosis. In addition, CD55 has been reported to be an essential host receptor for infection by the malaria parasite. Moreover, CD55 is a ligand of the seven-span transmembrane receptor CD97. Since CD55 is present in various cells, the functional role of CD55 has been expanded by showing that CD55 is associated with a variety of diseases, including cancer, malaria, protein-losing enteropathy, paroxysmal nocturnal hemoglobinuria, and autoimmune diseases. This review summarizes the current understanding of CD55 and the role of CD55 in these diseases. It also provides insight into the development of novel drugs for the diagnosis and treatment of diseases associated with CD55.
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Affiliation(s)
- So Hee Dho
- Radioisotope Research Division, Department of Research Reactor Utilization, Korea Atomic Energy Research Institute, Daejeon 34057, Korea
| | - Jae Cheong Lim
- Radioisotope Research Division, Department of Research Reactor Utilization, Korea Atomic Energy Research Institute, Daejeon 34057, Korea
| | - Lark Kyun Kim
- Severance Biomedical Science Institute and BK21 PLUS Project to Medical Sciences, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 06230, Korea
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13
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Agrawal P, Nawadkar R, Ojha H, Kumar J, Sahu A. Complement Evasion Strategies of Viruses: An Overview. Front Microbiol 2017; 8:1117. [PMID: 28670306 PMCID: PMC5472698 DOI: 10.3389/fmicb.2017.01117] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 05/31/2017] [Indexed: 12/11/2022] Open
Abstract
Being a major first line of immune defense, the complement system keeps a constant vigil against viruses. Its ability to recognize large panoply of viruses and virus-infected cells, and trigger the effector pathways, results in neutralization of viruses and killing of the infected cells. This selection pressure exerted by complement on viruses has made them evolve a multitude of countermeasures. These include targeting the recognition molecules for the avoidance of detection, targeting key enzymes and complexes of the complement pathways like C3 convertases and C5b-9 formation - either by encoding complement regulators or by recruiting membrane-bound and soluble host complement regulators, cleaving complement proteins by encoding protease, and inhibiting the synthesis of complement proteins. Additionally, viruses also exploit the complement system for their own benefit. For example, they use complement receptors as well as membrane regulators for cellular entry as well as their spread. Here, we provide an overview on the complement subversion mechanisms adopted by the members of various viral families including Poxviridae, Herpesviridae, Adenoviridae, Flaviviridae, Retroviridae, Picornaviridae, Astroviridae, Togaviridae, Orthomyxoviridae and Paramyxoviridae.
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Affiliation(s)
- Palak Agrawal
- Complement Biology Laboratory, National Centre for Cell Science, Savitribai Phule Pune UniversityPune, India
| | - Renuka Nawadkar
- Complement Biology Laboratory, National Centre for Cell Science, Savitribai Phule Pune UniversityPune, India
| | - Hina Ojha
- Complement Biology Laboratory, National Centre for Cell Science, Savitribai Phule Pune UniversityPune, India
| | - Jitendra Kumar
- Complement Biology Laboratory, National Centre for Cell Science, Savitribai Phule Pune UniversityPune, India
| | - Arvind Sahu
- Complement Biology Laboratory, National Centre for Cell Science, Savitribai Phule Pune UniversityPune, India
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14
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Bennett KM, Rooijakkers SHM, Gorham RD. Let's Tie the Knot: Marriage of Complement and Adaptive Immunity in Pathogen Evasion, for Better or Worse. Front Microbiol 2017; 8:89. [PMID: 28197139 PMCID: PMC5281603 DOI: 10.3389/fmicb.2017.00089] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 01/12/2017] [Indexed: 01/16/2023] Open
Abstract
The complement system is typically regarded as an effector arm of innate immunity, leading to recognition and killing of microbial invaders in body fluids. Consequently, pathogens have engaged in an arms race, evolving molecules that can interfere with proper complement responses. However, complement is no longer viewed as an isolated system, and links with other immune mechanisms are continually being discovered. Complement forms an important bridge between innate and adaptive immunity. While its roles in innate immunity are well-documented, its function in adaptive immunity is less characterized. Therefore, it is no surprise that the field of pathogenic complement evasion has focused on blockade of innate effector functions, while potential inhibition of adaptive immune responses (via complement) has been overlooked to a certain extent. In this review, we highlight past and recent developments on the involvement of complement in the adaptive immune response. We discuss the mechanisms by which complement aids in lymphocyte stimulation and regulation, as well as in antigen presentation. In addition, we discuss microbial complement evasion strategies, and highlight specific examples in the context of adaptive immune responses. These emerging ties between complement and adaptive immunity provide a catalyst for future discovery in not only the field of adaptive immune evasion but in elucidating new roles of complement.
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Affiliation(s)
- Kaila M Bennett
- Department of Medical Microbiology, University Medical Center Utrecht Utrecht, Netherlands
| | - Suzan H M Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht Utrecht, Netherlands
| | - Ronald D Gorham
- Department of Medical Microbiology, University Medical Center Utrecht Utrecht, Netherlands
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