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Xiang J, Chang Q, McLinden JH, Bhattarai N, Welch JL, Kaufman TM, Stapleton JT. Characterization of "Off-Target" Immune Modulation Induced by Live Attenuated Yellow Fever Vaccine. J Infect Dis 2024; 229:786-794. [PMID: 36994927 PMCID: PMC10938199 DOI: 10.1093/infdis/jiad086] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/09/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023] Open
Abstract
BACKGROUND Live attenuated vaccines alter immune functions and are associated with beneficial outcomes. We previously demonstrated that live attenuated yellow fever virus (YFV) vaccine (LA-YF-Vax) dampens T-cell receptor (TCR) signaling in vitro via an RNA-based mechanism. We examined study participants before and after LA-YF-Vax to assess TCR-mediated functions in vivo. METHODS Serum samples and peripheral blood mononuclear cells (PBMCs) were obtained before and after LA-YF-Vax (with or without additional vaccines) or quadrivalent influenza vaccine. TCR-mediated activation was determined by interleukin 2 release or phosphorylation of the lymphocyte-specific Src kinase. TCR-regulating phosphatase (protein tyrosine phosphatase receptor type E [PTPRE]) expression was also measured. RESULTS Compared with prevaccination findings, LA-YF-Vax recipient PBMCs demonstrated transient reduction in interleukin 2 release after TCR stimulation and PTPRE levels, unlike in control participants who received quadrivalent influenza vaccine. YFV was detected in 8 of 14 participants after LA-YF-Vax. After incubation of healthy donor PBMCs in serum-derived extracellular vesicles prepared from LA-YF-Vax recipients, TCR signaling and PTPRE levels were reduced after vaccination, even in participants without detectable YFV RNA. CONCLUSIONS LA-YF-Vax reduces TCR functions and PTPRE levels after vaccination. Extracellular vesicles from serum recapitulated this effect in healthy cells. This likely contributes to the reduced immunogenicity for heterologous vaccines after LA-YF-Vax administration. Identification of specific immune mechanisms related to vaccines should contribute to understanding of the "off-target," beneficial effects of live vaccines.
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Affiliation(s)
- J Xiang
- Iowa City Department of Veterans Affairs Healthcare System, University of Iowa, Iowa City, Iowa, USA
| | - Q Chang
- Iowa City Department of Veterans Affairs Healthcare System, University of Iowa, Iowa City, Iowa, USA
| | - J H McLinden
- Iowa City Department of Veterans Affairs Healthcare System, University of Iowa, Iowa City, Iowa, USA
| | - N Bhattarai
- Division of Cellular and Gene Therapies, Office of Tissues and Advanced Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - J L Welch
- Iowa City Department of Veterans Affairs Healthcare System, University of Iowa, Iowa City, Iowa, USA
| | - T M Kaufman
- Iowa City Department of Veterans Affairs Healthcare System, University of Iowa, Iowa City, Iowa, USA
| | - Jack T Stapleton
- Iowa City Department of Veterans Affairs Healthcare System, University of Iowa, Iowa City, Iowa, USA
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Malherbe DC, Mendy J, Vang L, Barnette PT, Reed J, Lakhashe SK, Owuor J, Gach JS, Legasse AW, Axthelm MK, LaBranche CC, Montefiori D, Forthal DN, Park B, Wilson JM, McLinden JH, Xiang J, Stapleton JT, Sacha JB, Haynes BF, Liao HX, Ruprecht RM, Smith J, Gurwith M, Haigwood NL, Alexander J. Combination Adenovirus and Protein Vaccines Prevent Infection or Reduce Viral Burden after Heterologous Clade C Simian-Human Immunodeficiency Virus Mucosal Challenge. J Virol 2018; 92:e01092-17. [PMID: 29093095 PMCID: PMC5752948 DOI: 10.1128/jvi.01092-17] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 10/13/2017] [Indexed: 01/24/2023] Open
Abstract
HIV vaccine development is focused on designing immunogens and delivery methods that elicit protective immunity. We evaluated a combination of adenovirus (Ad) vectors expressing HIV 1086.C (clade C) envelope glycoprotein (Env), SIV Gag p55, and human pegivirus GBV-C E2 glycoprotein. We compared replicating simian (SAd7) with nonreplicating human (Ad4) adenovirus-vectored vaccines paired with recombinant proteins in a novel prime-boost regimen in rhesus macaques, with the goal of eliciting protective immunity against SHIV challenge. In both vaccine groups, plasma and buccal Env-specific IgG, tier 1 heterologous neutralizing antibodies, and antibody-dependent cell-mediated viral inhibition were readily generated. High Env-specific T cell responses elicited in all vaccinees were significantly greater than responses targeting Gag. After three intrarectal exposures to heterologous tier 1 clade C SHIV, all 10 sham-vaccinated controls were infected, whereas 4/10 SAd7- and 3/10 Ad4-vaccinated macaques remained uninfected or maintained tightly controlled plasma viremia. Time to infection was significantly delayed in SAd7-vaccinated macaques compared to the controls. Cell-associated and plasma virus levels were significantly lower in each group of vaccinated macaques compared to controls; the lowest plasma viral burden was found in animals vaccinated with the SAd7 vectors, suggesting superior immunity conferred by the replicating simian vectors. Furthermore, higher V1V2-specific binding antibody titers correlated with viral control in the SAd7 vaccine group. Thus, recombinant Ad plus protein vaccines generated humoral and cellular immunity that was effective in either protecting from SHIV acquisition or significantly reducing viremia in animals that became infected, consequently supporting additional development of replicating Ad vectors as HIV vaccines.IMPORTANCE There is a well-acknowledged need for an effective AIDS vaccine that protects against HIV infection and limits in vivo viral replication and associated pathogenesis. Although replicating virus vectors have been advanced as HIV vaccine platforms, there have not been any direct comparisons of the replicating to the nonreplicating format. The present study directly compared the replicating SAd7 to nonreplicating Ad4 vectors in macaques and demonstrated that in the SAd7 vaccine group, the time to infection was significantly delayed compared to the control group, and V1V2 Env-specific binding antibodies correlated with viral outcomes. Viral control was significantly enhanced in vaccinated macaques compared to controls, and in infected SAd7-vaccinated macaques compared to Ad4-vaccinated macaques, suggesting that this vector may have conferred more effective immunity. Because blocking infection is so difficult with current vaccines, development of a vaccine that can limit viremia if infection occurs would be valuable. These data support further development of replicating adenovirus vectors.
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Affiliation(s)
- Delphine C Malherbe
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
| | | | - Lo Vang
- PaxVax, Inc., San Diego, California, USA
| | - Philip T Barnette
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
| | - Jason Reed
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, USA
| | - Samir K Lakhashe
- Department of Virology and Immunology, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Joshua Owuor
- Department of Virology and Immunology, Texas Biomedical Research Institute, San Antonio, Texas, USA
- Southwest National Primate Research Center, San Antonio, Texas, USA
| | - Johannes S Gach
- Division of Infectious Diseases, Department of Medicine, University of California, Irvine School of Medicine, Irvine, California, USA
| | - Alfred W Legasse
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
| | - Michael K Axthelm
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, USA
| | - Celia C LaBranche
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA
| | - David Montefiori
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | - Donald N Forthal
- Division of Infectious Diseases, Department of Medicine, University of California, Irvine School of Medicine, Irvine, California, USA
| | - Byung Park
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
| | - James M Wilson
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - James H McLinden
- The Iowa City Veterans Affairs Medical Center, Iowa City, Iowa, USA
- The University of Iowa, Iowa City, Iowa, USA
| | - Jinhua Xiang
- The Iowa City Veterans Affairs Medical Center, Iowa City, Iowa, USA
- The University of Iowa, Iowa City, Iowa, USA
| | - Jack T Stapleton
- The Iowa City Veterans Affairs Medical Center, Iowa City, Iowa, USA
- The University of Iowa, Iowa City, Iowa, USA
| | - Jonah B Sacha
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, USA
| | - Barton F Haynes
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Pathology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Hua-Xin Liao
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Ruth M Ruprecht
- Department of Virology and Immunology, Texas Biomedical Research Institute, San Antonio, Texas, USA
- Southwest National Primate Research Center, San Antonio, Texas, USA
| | | | | | - Nancy L Haigwood
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, USA
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McLinden JH, Bhattarai N, Stapleton JT, Chang Q, Kaufman TM, Cassel SL, Sutterwala FS, Haim H, Houtman JC, Xiang J. Yellow Fever Virus, but Not Zika Virus or Dengue Virus, Inhibits T-Cell Receptor-Mediated T-Cell Function by an RNA-Based Mechanism. J Infect Dis 2017; 216:1164-1175. [PMID: 28968905 PMCID: PMC5853456 DOI: 10.1093/infdis/jix462] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 08/13/2017] [Indexed: 01/03/2023] Open
Abstract
The Flavivirus genus within the Flaviviridae family is comprised of many important human pathogens including yellow fever virus (YFV), dengue virus (DENV), and Zika virus (ZKV), all of which are global public health concerns. Although the related flaviviruses hepatitis C virus and human pegivirus (formerly named GBV-C) interfere with T-cell receptor (TCR) signaling by novel RNA and protein-based mechanisms, the effect of other flaviviruses on TCR signaling is unknown. Here, we studied the effect of YFV, DENV, and ZKV on TCR signaling. Both YFV and ZKV replicated in human T cells in vitro; however, only YFV inhibited TCR signaling. This effect was mediated at least in part by the YFV envelope (env) protein coding RNA. Deletion mutagenesis studies demonstrated that expression of a short, YFV env RNA motif (vsRNA) was required and sufficient to inhibit TCR signaling. Expression of this vsRNA and YFV infection of T cells reduced the expression of a Src-kinase regulatory phosphatase (PTPRE), while ZKV infection did not. YFV infection in mice resulted in impaired TCR signaling and PTPRE expression, with associated reduction in murine response to experimental ovalbumin vaccination. Together, these data suggest that viruses within the flavivirus genus inhibit TCR signaling in a species-dependent manner.
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Affiliation(s)
- James H McLinden
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
| | - Nirjal Bhattarai
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
| | - Jack T Stapleton
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
- Department of Microbiology, University of Iowa, Iowa City
| | - Qing Chang
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
| | - Thomas M Kaufman
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
| | - Suzanne L Cassel
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
| | - Fayyaz S Sutterwala
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
| | - Hillel Haim
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
| | - Jon C Houtman
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
- Department of Microbiology, University of Iowa, Iowa City
| | - Jinhua Xiang
- Research Service, Iowa City Veterans Affairs Medical Center
- Department of Internal Medicine, University of Iowa, Iowa City
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Chivero ET, Bhattarai N, McLinden JH, Xiang J, Stapleton JT. Human Pegivirus (HPgV; formerly known as GBV-C) inhibits IL-12 dependent natural killer cell function. Virology 2015; 485:116-27. [PMID: 26245365 DOI: 10.1016/j.virol.2015.07.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 07/02/2015] [Accepted: 07/13/2015] [Indexed: 02/06/2023]
Abstract
Human Pegivirus (HPgV, formally GB virus C) infects lymphocytes and NK cells in vivo, and infection is associated with reduced T cell and NK cell activation in HIV-infected individuals. The mechanism by which HPgV inhibits NK cell activation has not been assessed. Following IL-12 stimulation, IFNγ expression was lower in HIV-HPgV co-infected subjects compared to HIV mono-infected subjects (p=0.02). In addition, HPgV positive human sera, extracellular vesicles containing E2 protein, recombinant E2 protein and synthetic E2 peptides containing a predicted Tyk2 interacting motif inhibited NK cell IL-12-mediated IFNγ release. E2 protein also inhibited Tyk2 activation following IL-12 stimulation. In contrast, cytolytic NK cell function was not altered by HPgV. Inhibition of NK cell-induced proinflammatory/antiviral cytokines may contribute to both HPgV persistence and reduced immune activation during HIV-coinfection. Understanding mechanisms by which HPgV alters immune activation may contribute towards novel immunomodulatory therapies to treat HIV and inflammatory diseases.
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Affiliation(s)
- Ernest T Chivero
- The Iowa City Veterans Affairs Medical Center The University of Iowa, Iowa City, IA 52242, USA; Interdisciplinary program in Molecular and Cellular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Nirjal Bhattarai
- The Iowa City Veterans Affairs Medical Center The University of Iowa, Iowa City, IA 52242, USA; Department of Internal Medicine, The University of Iowa, Iowa City, IA 52242, USA
| | - James H McLinden
- The Iowa City Veterans Affairs Medical Center The University of Iowa, Iowa City, IA 52242, USA; Department of Internal Medicine, The University of Iowa, Iowa City, IA 52242, USA
| | - Jinhua Xiang
- The Iowa City Veterans Affairs Medical Center The University of Iowa, Iowa City, IA 52242, USA; Department of Internal Medicine, The University of Iowa, Iowa City, IA 52242, USA
| | - Jack T Stapleton
- The Iowa City Veterans Affairs Medical Center The University of Iowa, Iowa City, IA 52242, USA; Interdisciplinary program in Molecular and Cellular Biology, The University of Iowa, Iowa City, IA 52242, USA; Department of Internal Medicine, The University of Iowa, Iowa City, IA 52242, USA; Department of Microbiology, The University of Iowa, Iowa City, IA 52242, USA.
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Abstract
Some retrospective studies suggest an association between infection with GB virus-C (GBV-C) and non-Hodgkin lymphoma (NHL). We evaluated this association prospectively in a nested case-control study within the U.S. Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. Cases (N = 658) and controls (N = 1,316) were individually matched by age, sex, race/ethnicity, timing of study entry, and sample selection. Prediagnostic PLCO serum samples were tested for GBV-C RNA (as a measure of active infection) and E2 antibody (active or resolved infection). Logistic regression was used to estimate odds ratios (OR) for the association between GBV-C and NHL overall and NHL subtypes. Twelve cases (1.8%) and seven controls (0.5%) were GBV-C RNA-positive. GBV-C RNA positivity was associated with NHL overall [OR, 3.43; 95% confidence interval (CI), 1.35-8.71] and, based on small numbers, diffuse large B-cell lymphoma (OR, 5.31; 95% CI, 1.54-18.36). The association with NHL persisted when the interval between testing and selection was greater than 4 years (OR, 6.00; 95% CI, 1.21-29.73). In contrast, E2 antibody positivity was not associated with NHL risk (OR, 1.08; 95% CI, 0.74-1.58). Our study demonstrates that GBV-C infection precedes development of NHL. GBV-C infection may play an etiologic role in a small proportion of NHL cases, perhaps by causing chronic immune stimulation or impaired immunosurveillance.
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Affiliation(s)
- Cindy M Chang
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland.
| | - Jack T Stapleton
- Department of Internal Medicine, Iowa City Veterans Affairs Medical Center, University of Iowa, Iowa City, Iowa
| | - Donna Klinzman
- Department of Internal Medicine, Iowa City Veterans Affairs Medical Center, University of Iowa, Iowa City, Iowa
| | - James H McLinden
- Department of Internal Medicine, Iowa City Veterans Affairs Medical Center, University of Iowa, Iowa City, Iowa
| | - Mark P Purdue
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland
| | - Hormuzd A Katki
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland
| | - Eric A Engels
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland
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Stapleton JT, Xiang J, McLinden JH, Bhattarai N, Chivero ET, Klinzman D, Kaufman TM, Chang Q. A novel T cell evasion mechanism in persistent RNA virus infection. Trans Am Clin Climatol Assoc 2014; 125:14-26. [PMID: 25125715 PMCID: PMC4112695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Hepatitis C virus (HCV) and GB virus type C (GBV-C) are associated with impaired T cell function despite the fact that HCV replicates in hepatocytes and GBV-C in a small proportion of lymphocytes. Recently, we showed that HCV and GBV-C E2-envelope proteins reduce T cell activation via the T cell receptor (TCR) by competing for phosphorylation with a critical kinase in the TCR signaling cascade (Lck). E2 interfered with TCR signaling in E2 expressing cells and in bystander cells. The bystander effect was mediated by virus particles and extracellular microvesicular particles (exosomes). Multiple kinase substrate sites are predicted to reside on viral structural proteins and based on bioinformatic predictions, many RNA virus pathogens may interfere with TCR signaling via a similar mechanism. Identification of T cell inhibitory effects of virus structural proteins may provide novel approaches to enhance the immunogenicity and memory of viral vaccines.
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Affiliation(s)
- Jack T. Stapleton
- Correspondence and reprint requests: Jack T. Stapleton,
Department of Internal Medicine, SW54, GH, University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242319-356-3168319-356-4600
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Bhattarai N, McLinden JH, Xiang J, Landay AL, Chivero ET, Stapleton JT. GB virus C particles inhibit T cell activation via envelope E2 protein-mediated inhibition of TCR signaling. J Immunol 2013; 190:6351-9. [PMID: 23686495 DOI: 10.4049/jimmunol.1300589] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Viruses enter into complex interactions within human hosts, leading to facilitation or suppression of each other's replication. Upon coinfection, GB virus C (GBV-C) suppresses HIV-1 replication in vivo and in vitro, and GBV-C coinfection is associated with prolonged survival in HIV-infected people. GBV-C is a lymphotropic virus capable of persistent infection. GBV-C infection is associated with reduced T cell activation in HIV-infected humans, and immune activation is a critical component of HIV disease pathogenesis. We demonstrate that serum GBV-C particles inhibited activation of primary human T cells. T cell activation inhibition was mediated by the envelope glycoprotein E2, because expression of E2 inhibited TCR-mediated activation of Lck. The region on the E2 protein was characterized and revealed a highly conserved peptide motif sufficient to inhibit TCR-mediated signaling. The E2 region contained a predicted Lck substrate site, and substitution of an alanine or histidine for the tyrosine reversed TCR-signaling inhibition. GBV-C E2 protein and a synthetic peptide representing the inhibitory amino acid sequence were phosphorylated by Lck in vitro. The synthetic peptide also inhibited TCR-mediated activation of primary human CD4(+) and CD8(+) T cells. Extracellular microvesicles from GBV-C E2-expressing cells contained E2 protein and inhibited TCR signaling in bystander T cells not expressing E2. Thus, GBV-C reduced global T cell activation via competition between its envelope protein E2 and Lck following TCR engagement. This novel inhibitory mechanism of T cell activation may provide new approaches for HIV and immunoactivation therapy.
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Affiliation(s)
- Nirjal Bhattarai
- Iowa City Veterans Affairs Medical Center, Iowa City, IA 52242, USA
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Zhang J, Chaloner K, McLinden JH, Stapleton JT. Bayesian analysis and classification of two enzyme-linked immunosorbent assay tests without a gold standard. Stat Med 2013; 32:4102-17. [DOI: 10.1002/sim.5816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 03/18/2013] [Indexed: 11/09/2022]
Affiliation(s)
| | | | - James H. McLinden
- Department of Internal Medicine; University of Iowa; Iowa City; IA; U.S.A
| | - Jack T. Stapleton
- Department of Internal Medicine; University of Iowa; Iowa City; IA; U.S.A
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McLinden JH, Stapleton JT, Klinzman D, Murthy KK, Chang Q, Kaufman TM, Bhattarai N, Xiang J. Chimpanzee GB virus C and GB virus A E2 envelope glycoproteins contain a peptide motif that inhibits human immunodeficiency virus type 1 replication in human CD4⁺ T-cells. J Gen Virol 2013; 94:774-782. [PMID: 23288422 DOI: 10.1099/vir.0.047126-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
GB virus type C (GBV-C) is a lymphotropic virus that can cause persistent infection in humans. GBV-C is not associated with any disease, but is associated with reduced mortality in human immunodeficiency virus type 1 (HIV-1)-infected individuals. Related viruses have been isolated from chimpanzees (GBV-Ccpz) and from New World primates (GB virus type A, GBV-A). These viruses are also capable of establishing persistent infection. We determined the nucleotide sequence encoding the envelope glycoprotein (E2) of two GBV-Ccpz isolates obtained from the sera of captive chimpanzees. The deduced GBV-Ccpz E2 protein differed from human GBV-C by 31 % at the amino acid level. Similar to human GBV-C E2, expression of GBV-Ccpz E2 in a tet-off human CD4(+) Jurkat T-cell line significantly inhibited the replication of diverse HIV-1 isolates. This anti-HIV-replication effect of GBV-Ccpz E2 protein was reversed by maintaining cells in doxycycline to reduce E2 expression. Previously, we found a 17 aa region within human GBV-C E2 that was sufficient to inhibit HIV-1. Although GBV-Ccpz E2 differed by 3 aa differences in this region, the chimpanzee GBV-C 17mer E2 peptide inhibited HIV-1 replication. Similarly, the GBV-A peptide that aligns with this GBV-C E2 region inhibited HIV-1 replication despite sharing only 5 aa with the human GBV-C E2 sequence. Thus, despite amino acid differences, the peptide region on both the GBV-Ccpz and the GBV-A E2 protein inhibit HIV-1 replication similar to human GBV-C. Consequently, GBV-Ccpz or GBV-A infection of non-human primates may provide an animal model to study GB virus-HIV interactions.
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Affiliation(s)
- James H McLinden
- Department of Internal Medicine, Division of Infectious Diseases, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA
| | - Jack T Stapleton
- Interdisciplinary Program on Molecular and Cellular Biology, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA.,Department of Internal Medicine, Division of Infectious Diseases, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA
| | - Donna Klinzman
- Department of Internal Medicine, Division of Infectious Diseases, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA
| | - Krishna K Murthy
- Department of Virology and Immunology, Texas Biomedical Research Institute, San Antonio, TX 78227, USA
| | - Qing Chang
- Department of Internal Medicine, Division of Infectious Diseases, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA
| | - Thomas M Kaufman
- Department of Internal Medicine, Division of Infectious Diseases, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA
| | - Nirjal Bhattarai
- Interdisciplinary Program on Molecular and Cellular Biology, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA.,Department of Internal Medicine, Division of Infectious Diseases, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA
| | - Jinhua Xiang
- Department of Internal Medicine, Division of Infectious Diseases, Iowa City Veterans Affairs Medical Center and the University of Iowa, Iowa City, IA 52242, USA
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Bhattarai N, McLinden JH, Xiang J, Kaufman TM, Stapleton JT. GB virus C envelope protein E2 inhibits TCR-induced IL-2 production and alters IL-2-signaling pathways. J Immunol 2012; 189:2211-6. [PMID: 22844114 DOI: 10.4049/jimmunol.1201324] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
GB virus type C (GBV-C) viremia is associated with reduced CD4+ T cell expansion following IL-2 therapy and with a reduction in T cell activation in HIV-infected individuals. The mechanism(s) by which GBV-C might alter T cell activation or IL-2 signaling have not been studied. In this study, we assess IL-2 release, IL-2R expression, IL-2 signaling, and cell proliferation in tet-off Jurkat cells expressing the GBV-C envelope glycoprotein (E2) following activation through the TCR. TCR activation was induced by incubation in anti-CD3/CD28 Abs. IL-2 release was measured by ELISA, STAT5 phosphorylation was assessed by immunoblot, and IL-2Rα (CD25) expression and cell proliferation were determined by flow cytometry. IL-2 and IL-2Rα steady-state mRNA levels were measured by real-time PCR. GBV-C E2 expression significantly inhibited IL-2 release, CD25 expression, STAT5 phosphorylation, and cellular proliferation in Jurkat cells following activation through the TCR compared with control cell lines. Reducing E2 expression by doxycycline reversed the inhibitory effects observed in the E2-expressing cells. The N-terminal 219 aa of E2 was sufficient to inhibit IL-2 signaling. Addition of purified recombinant GBV-C E2 protein to primary human CD4+ and CD8+ T cells inhibited TCR activation-induced IL-2 release and upregulation of IL-2Rα expression. These data provide evidence that the GBV-C E2 protein may contribute to the block in CD4+ T cell expansion following IL-2 therapy in HIV-infected individuals. Furthermore, the effects of GBV-C on IL-2 and IL-2-signaling pathways may contribute to the reduction in chronic immune activation observed in GBV-C/HIV-coinfected individuals.
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Affiliation(s)
- Nirjal Bhattarai
- Iowa City Veterans Affairs Medical Center, Iowa City, IA 52242, USA
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Xiang J, McLinden JH, Kaufman TM, Mohr EL, Bhattarai N, Chang Q, Stapleton JT. Characterization of a peptide domain within the GB virus C envelope glycoprotein (E2) that inhibits HIV replication. Virology 2012; 430:53-62. [PMID: 22608061 DOI: 10.1016/j.virol.2012.04.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 04/26/2012] [Accepted: 04/29/2012] [Indexed: 12/15/2022]
Abstract
GB virus C (GBV-C) infection is associated with prolonged survival in HIV-infected cohorts, and GBV-C E2 protein inhibits HIV entry when added to CD4+ T cells. To further characterize E2 effects on HIV replication, stably transfected Jurkat cell lines expressing GBV-C E2 or control sequences were infected with HIV and replication was measured. HIV replication (all 6 isolates studied) was inhibited in all cell lines expressing a region of 17 amino acids of GBV-C E2, but not in cell lines expressing E2 without this region. In contrast, mumps and yellow fever virus replication was not inhibited by E2 protein expression. Synthetic GBV-C E2 17mer peptides did not inhibit HIV replication unless they were fused to a tat-protein-transduction-domain (TAT) for cellular uptake. These data identify the region of GBV-C E2 protein involved in HIV inhibition, and suggest that this GBV-C E2 peptide must gain entry into the cell to inhibit HIV.
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Affiliation(s)
- Jinhua Xiang
- Department of Internal Medicine, Iowa City Veterans Affairs Medical Center and University of Iowa, IA 52242, USA.
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12
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Rydze RT, Xiang J, McLinden JH, Stapleton JT. GB virus type C infection polarizes T-cell cytokine gene expression toward a Th1 cytokine profile via NS5A protein expression. J Infect Dis 2012; 206:69-72. [PMID: 22535999 DOI: 10.1093/infdis/jis312] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Human immunodeficiency virus (HIV) disease progression is associated with a helper T cell 1 (Th1) to helper T cell 2 (Th2) cytokine profile switch. Persistent GB virus type C (GBV-C) infection is associated with survival and a serum Th1 cytokine profile in HIV-infected individuals. We found that GBV-C infection increased gene expression of Th1 cytokines and decreased Th2 cytokine expression in peripheral blood mononuclear cells. Furthermore, expression of GBV-C NS5A protein in a CD4(+) cell line resulted in upregulation of Th1 cytokines (tumor necrosis factor α) and downregulation of Th2 cytokines (interleukin 4, interleukin 5, interleukin 10, interleukin 13). GBV-C-induced modulation in T-cell cytokines may contribute to the beneficial effect of GBV-C in HIV-infected individuals.
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Affiliation(s)
- Robert T Rydze
- Iowa City Veterans Affairs Medical Center, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Doris Duke Scholars Program, Iowa City, Iowa, USA.
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13
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Abstract
GB virus C (GBV-C) is a common, non-pathogenic human virus that infects lymphocytes. Persistent GBV-C infection of humans with coexistent human immunodeficiency virus (HIV) infection is associated with prolonged survival, and GBV-C replication inhibits HIV replication in vitro. A GBV-C virus variant was identified in chimpanzees in 1998 and was named GBV-Ctrog or GBV-Ccpz. The prevalence and natural history of GBV-C in chimpanzees remains uncharacterized. We examined the sera from 235 captive chimpanzees for the presence of GBV-C viraemia, viral persistence and clearance, E2 antibody kinetics and RNA sequence diversity. Sequences from six isolates shared more sequence identity with GBV-Ccpz than with human GBV-C. The prevalence of GBV-Ccpz viraemia and E2 antibody in chimpanzees (2.5 and 11 %, respectively) was similar to human GBV-C prevalence in healthy human blood donors (1.8 and 9 %, respectively). Persistent GBV-Ccpz infection occurred in two of the six viraemic animals and was documented for 19 years in one animal. Host subspecies troglodyte GBV-C isolates and published verus GBV-C isolates shared a high degree of sequence identity, suggesting that GBV-C in chimpanzees should be identified with a chimpanzee designation (GBV-Ccpz). The prevalence and natural history of chimpanzee GBV-C variant (GBV-Ccpz) appears to be similar to human GBV-C infection. The chimpanzee could serve as an animal model to study HIV–GBV-C co-infection.
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Affiliation(s)
- Emma L Mohr
- Department of Internal Medicine, Division of Infectious Diseases, Iowa City Veterans Affairs Medical Center and The University of Iowa, Iowa City, IA 52242, USA
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14
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Mohr EL, Xiang J, McLinden JH, Kaufman TM, Chang Q, Montefiori DC, Klinzman D, Stapleton JT. GB virus type C envelope protein E2 elicits antibodies that react with a cellular antigen on HIV-1 particles and neutralize diverse HIV-1 isolates. J Immunol 2010; 185:4496-505. [PMID: 20826757 DOI: 10.4049/jimmunol.1001980] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Broadly neutralizing Abs to HIV-1 are well described; however, identification of Ags that elicit these Abs has proven difficult. Persistent infection with GB virus type C (GBV-C) is associated with prolonged survival in HIV-1-infected individuals, and among those without HIV-1 viremia, the presence of Ab to GBV-C glycoprotein E2 is also associated with survival. GBV-C E2 protein inhibits HIV-1 entry, and an antigenic peptide within E2 interferes with gp41-induced membrane perturbations in vitro, suggesting the possibility of structural mimicry between GBV-C E2 protein and HIV-1 particles. Naturally occurring human and experimentally induced GBV-C E2 Abs were examined for their ability to neutralize infectious HIV-1 particles and HIV-1-enveloped pseudovirus particles. All GBV-C E2 Abs neutralized diverse isolates of HIV-1 with the exception of rabbit anti-peptide Abs raised against a synthetic GBV-C E2 peptide. Rabbit anti-GBV-C E2 Abs neutralized HIV-1-pseudotyped retrovirus particles but not HIV-1-pseudotyped vesicular stomatitis virus particles, and E2 Abs immune-precipitated HIV-1 gag particles containing the vesicular stomatitis virus type G envelope, HIV-1 envelope, GBV-C envelope, or no viral envelope. The Abs did not neutralize or immune-precipitate mumps or yellow fever viruses. Rabbit GBV-C E2 Abs inhibited HIV attachment to cells but did not inhibit entry following attachment. Taken together, these data indicate that the GBV-C E2 protein has a structural motif that elicits Abs that cross-react with a cellular Ag present on retrovirus particles, independent of HIV-1 envelope glycoproteins. The data provide evidence that a heterologous viral protein can induce HIV-1-neutralizing Abs.
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Affiliation(s)
- Emma L Mohr
- Division of Infectious Diseases, Department of Internal Medicine, Iowa City Veterans Affairs Medical Center, Iowa City, IA 52242, USA
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15
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Xiang J, McLinden JH, Rydze RA, Chang Q, Kaufman TM, Klinzman D, Stapleton JT. Viruses within the Flaviviridae decrease CD4 expression and inhibit HIV replication in human CD4+ cells. J Immunol 2010; 183:7860-9. [PMID: 19923460 DOI: 10.4049/jimmunol.0902276] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Viral infections alter host cell homeostasis and this may lead to immune evasion and/or interfere with the replication of other microbes in coinfected hosts. Two flaviviruses are associated with a reduction in HIV replication or improved survival in HIV-infected people (dengue virus (DV) and GB virus type C (GBV-C)). GBV-C infection and expression of the GBV-C nonstructural protein 5A (NS5A) and the DV NS5 protein in CD4(+) T cells inhibit HIV replication in vitro. To determine whether the inhibitory effect on HIV replication is conserved among other flaviviruses and to characterize mechanism(s) of HIV inhibition, the NS5 proteins of GBV-C, DV, hepatitis C virus, West Nile virus, and yellow fever virus (YFV; vaccine strain 17D) were expressed in CD4(+) T cells. All NS5 proteins inhibited HIV replication. This correlated with decreased steady-state CD4 mRNA levels and reduced cell surface CD4 protein expression. Infection of CD4(+) T cells and macrophages with YFV (17D vaccine strain) also inhibited HIV replication and decreased CD4 gene expression. In contrast, mumps virus was not inhibited by the expression of flavivirus NS5 protein or by YFV infection, and mumps infection did not alter CD4 mRNA or protein levels. In summary, CD4 gene expression is decreased by all human flavivirus NS5 proteins studied. CD4 regulation by flaviviruses may interfere with innate and adaptive immunity and contribute to in vitro HIV replication inhibition. Characterization of the mechanisms by which flaviviruses regulate CD4 expression may lead to novel therapeutic strategies for HIV and immunological diseases.
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Affiliation(s)
- Jinhua Xiang
- Department of Internal Medicine, Iowa City Veterans Affairs Medical Center and University of Iowa, Iowa City, IA 52242, USA
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16
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17
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Xiang J, McLinden JH, Chang Q, Jordan EL, Stapleton JT. Characterization of a peptide domain within the GB virus C NS5A phosphoprotein that inhibits HIV replication. PLoS One 2008; 3:e2580. [PMID: 18596910 PMCID: PMC2440355 DOI: 10.1371/journal.pone.0002580] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Accepted: 05/29/2008] [Indexed: 01/30/2023] Open
Abstract
Background GBV-C infection is associated with prolonged survival in HIV-infected people and GBV-C inhibits HIV replication in co-infection models. Expression of the GBV-C nonstructural phosphoprotein 5A (NS5A) decreases surface levels of the HIV co-receptor CXCR4, induces the release of SDF-1 and inhibits HIV replication in Jurkat CD4+ T cell lines. Methodology/Principal Findings Jurkat cell lines stably expressing NS5A protein and peptides were generated and HIV replication in these cell lines assessed. HIV replication was significantly inhibited in all cell lines expressing NS5A amino acids 152–165. Substitution of an either alanine or glycine for the serine at position 158 (S158A or S158G) resulted in a significant decrease in the HIV inhibitory effect. In contrast, substituting a phosphomimetic amino acid (glutamic acid; S158E) inhibited HIV as well as the parent peptide. HIV inhibition was associated with lower levels of surface expression of the HIV co-receptor CXCR4 and increased release of the CXCR4 ligand, SDF-1 compared to control cells. Incubation of CD4+ T cell lines with synthetic peptides containing amino acids 152–167 or the S158E mutant peptide prior to HIV infection resulted in HIV replication inhibition compared to control peptides. Conclusions/Significance Expression of GBV-C NS5A amino acids 152–165 are sufficient to inhibit HIV replication in vitro, and the serine at position 158 appears important for this effect through either phosphorylation or structural changes in this peptide. The addition of synthetic peptides containing 152–167 or the S158E substitution to Jurkat cells resulted in HIV replication inhibition in vitro. These data suggest that GBV-C peptides or a peptide mimetic may offer a novel, cellular-based approach to antiretroviral therapy.
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Affiliation(s)
- Jinhua Xiang
- Iowa City VA Medical Center and the University of Iowa, Iowa City, Iowa, United States of America
| | - James H. McLinden
- Iowa City VA Medical Center and the University of Iowa, Iowa City, Iowa, United States of America
| | - Qing Chang
- Iowa City VA Medical Center and the University of Iowa, Iowa City, Iowa, United States of America
| | - Emma L. Jordan
- Iowa City VA Medical Center and the University of Iowa, Iowa City, Iowa, United States of America
| | - Jack T. Stapleton
- Iowa City VA Medical Center and the University of Iowa, Iowa City, Iowa, United States of America
- * E-mail:
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18
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Chang Q, McLinden JH, Stapleton JT, Sathar MA, Xiang J. Expression of GB virus C NS5A protein from genotypes 1, 2, 3 and 5 and a 30 aa NS5A fragment inhibit human immunodeficiency virus type 1 replication in a CD4+ T-lymphocyte cell line. J Gen Virol 2008; 88:3341-3346. [PMID: 18024904 DOI: 10.1099/vir.0.83198-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
GB virus type C (GBV-C) is a common human flavivirus that has been associated with prolonged survival in HIV-positive individuals in several, though not all, epidemiological studies. There are five distinct GBV-C genotypes that are geographically localized, and it has been speculated that GBV-C genotypic differences may explain variable outcomes observed in different clinical studies. Expression of an 85 aa fragment of the GBV-C NS5A phosphoprotein (genotype 2) in a CD4+ T cell line (Jurkat) resulted in inhibition of HIV replication, mediated in part by decreased surface expression of the HIV coreceptor CXCR4 and upregulation of SDF-1. We expressed the NS5A protein from genotypes 1, 2, 3 and 5 in Jurkat cells, and demonstrated that all genotypes inhibited HIV replication. Further deletion mapping demonstrated that expression of a 30 aa fragment resulted in decreased CXCR4 surface expression, upregulation of SDF-1 and inhibition of HIV replication.
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Affiliation(s)
- Qing Chang
- Iowa City VA Medical Center and the University of Iowa, Iowa City, IA 52246, USA
| | - James H McLinden
- Iowa City VA Medical Center and the University of Iowa, Iowa City, IA 52246, USA
| | - Jack T Stapleton
- Iowa City VA Medical Center and the University of Iowa, Iowa City, IA 52246, USA
| | - M Aslam Sathar
- Nelson R. Mandela School of Medicine, University of Kwazulu-Natal, South Africa
| | - Jinhua Xiang
- Iowa City VA Medical Center and the University of Iowa, Iowa City, IA 52246, USA
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19
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Abstract
The addition of GB virus C (GBV-C) E2 protein to cells inhibits HIV replication in vitro, presumably triggered by interactions with a specific cellular receptor. Indirect evidence suggests that CD81 is the GBV-C E2 cellular receptor. We found that E2 binding to cells was not dependent upon human CD81, and that soluble CD81 did not compete with GBV-C E2 for cell binding. GBV-C E2 protein thus does not appear to interact with CD81.
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Affiliation(s)
- Thomas M Kaufman
- Iowa City VA Medical Center and the University of Iowa, Iowa City, Iowa, USA
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20
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McLinden JH, Kaufman TM, Xiang J, Chang Q, Klinzman D, Engel AM, Hess G, Schmidt U, Houghton M, Stapleton JT. Characterization of an immunodominant antigenic site on GB virus C glycoprotein E2 that is involved in cell binding. J Virol 2006; 80:12131-40. [PMID: 17035329 PMCID: PMC1676310 DOI: 10.1128/jvi.01206-06] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
GB virus type C (GBV-C) is a human flavivirus that may cause persistent infection, although most infected individuals clear viremia and develop antibodies to the envelope glycoprotein E2. To study GBV-C E2 antigenicity and cell binding, murine anti-E2 monoclonal antibodies (MAbs) were evaluated to topologically map immunogenic sites on GBV-C E2 and for the ability to detect or block recombinant E2 binding to various cell lines. Five competition groups of MAbs were identified. Groups I and II did not compete with each other. Group III competed with both groups I and II. Group IV did not compete with group I, II, or III. One MAb competed with all of the other MAbs, suggesting that the epitopes bound by these MAbs are intimately related. Individually, none of the MAbs competed extensively with polyclonal human convalescent antibody (PcAb); however, combinations of all five MAb groups completely blocked PcAb binding to E2, suggesting that the epitopes bound by these MAbs form a single, immunodominant antigenic site. Only group I and III MAbs detected purified recombinant E2 bound to cells in binding assays. In contrast, group II MAbs neutralized the binding of E2 to cells. Both PcAb and MAbs were conformation dependent, with the exception of one group II MAb (M6). M6 bound to a five-amino-acid sequence on E2 if the peptide included four C-terminal or eight N-terminal residues, suggesting that the GBV-C E2 protein contains a single immunodominant antigenic site which includes a complex epitope that is involved in specific cellular binding.
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Affiliation(s)
- James H McLinden
- Department of Internal Medicine, SW54, GH, The University of Iowa, Iowa City, IA 52242, USA
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21
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Xiang J, McLinden JH, Chang Q, Kaufman TM, Stapleton JT. An 85-aa segment of the GB virus type C NS5A phosphoprotein inhibits HIV-1 replication in CD4+ Jurkat T cells. Proc Natl Acad Sci U S A 2006; 103:15570-5. [PMID: 17030806 PMCID: PMC1622863 DOI: 10.1073/pnas.0604728103] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
GB virus type C (GBV-C) is an apparently nonpathogenic virus that replicates in T and B lymphocytes and is a common cause of persistent human infection. Among HIV-1-infected individuals, persistent coinfection with GBV-C is associated with prolonged survival, and infection of blood mononuclear cells or CD4+ T cells with GBV-C and HIV in vitro results in significantly reduced HIV-1 replication. To date, the viral protein(s) that lead to HIV inhibition have not been identified. The GBV-C nonstructural phosphoprotein (NS5A) is predicted to have pleotropic effects on cells, including interactions with the IFN-induced dsRNA-activated protein kinase (PKR). We studied GBV-C NS5A to determine whether it is involved in inhibition of HIV replication. GBV-C NS5A protein from an isolate that was cleared by IFN therapy did not inhibit PKR, whereas NS5A from an isolate that was not cleared by IFN-inhibited PKR function in a yeast genetic system. Both of these GBV-C NS5A proteins were expressed in a CD4+ T cell line (Jurkat), and both induced a potent, dose-dependent inhibition of HIV-1 replication, thus the effect was independent of PKR inhibition. NS5A induced the release of the chemokine SDF-1 and decreased surface expression of the HIV coreceptor CXCR4, potentially explaining the HIV inhibition. Deletion mapping of the NS5A protein found that an 85-aa region between amino acids 152 and 237 inhibits HIV-1 replication. Thus, GBV-C NS5A protein alters the cellular milieu necessary for HIV-1 replication and may provide a previously undescribed therapeutic approach for anti-HIV therapy.
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Affiliation(s)
- Jinhua Xiang
- Research Service and Department of Internal Medicine, Iowa City Veterans Affairs Medical Center and University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242, USA.
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22
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Xiang J, Sathar MA, McLinden JH, Klinzman D, Chang Q, Stapleton JT. South African GB Virus C Isolates: Interactions between Genotypes 1 and 5 Isolates and HIV. J Infect Dis 2005; 192:2147-51. [PMID: 16288381 DOI: 10.1086/498170] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2005] [Accepted: 07/08/2005] [Indexed: 11/04/2022] Open
Abstract
GB virus C (GBV-C) is a common, apparently nonpathogenic human flavivirus that has been associated in some studies with prolonged survival in human immunodeficiency virus (HIV)-positive persons. There are 5 distinct GBV-C genotypes localized to specific geographic regions, and genotype 2 has been previously shown to inhibit HIV replication in vitro in lymphocyte cultures. We identified GBV-C virus isolates representing genotypes 1, 2, and 5 in samples from South African blood donors. GBV-C genotype 1 and 5 isolates replicated in lymphocyte culture, inhibited X4 and R5 HIV-1 isolates, and induced RANTES and stromal-derived factor-1 chemokines in vitro. Thus, African GBV-C genotypes can inhibit HIV replication in vitro.
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Affiliation(s)
- Jinhua Xiang
- Research and Medical Service, Iowa City VA Medical Center, Iowa City, 52242, USA
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23
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Stapleton JT, Raina V, Winokur PL, Walters K, Klinzman D, Rosen E, McLinden JH. Antigenic and immunogenic properties of recombinant hepatitis A virus 14S and 70S subviral particles. J Virol 1993; 67:1080-5. [PMID: 7678298 PMCID: PMC237464 DOI: 10.1128/jvi.67.2.1080-1085.1993] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Hepatitis A virus (HAV) has an immunodominant neutralization antigenic site. By using a panel of monoclonal antibodies targeted against the HAV neutralization antigenic site, it was shown that three epitopes within this site are present on 14S subunits (pentamers of the structural unit). In contrast, two other epitopes within this site are formed upon assembly of 14S subunits into capsids. Thus, the epitopes recognized by these two monoclonal antibodies are formed either by a conformational change in the antigenic site or by the juxtaposition of epitope fragments present on different 14S subunits during assembly of 14S into 70S particles. Both 14S and 70S particles elicited HAV-neutralizing antibodies in mice; thus, these particles may be useful for HAV vaccine development.
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24
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Abstract
Recombinant polyhedrin proteins of the baculovirus Autographa californica nuclear polyhedrosis virus were constructed to serve as immunologic carriers of foreign epitopes. Several recombinants containing an influenza haemagglutinin epitope were obtained. Three of the five recombinants formed occlusion bodies (OBs) and two did not. All of the recombinant polyhedrin proteins reacted with a monoclonal antibody (mAb) specific for an influenza epitope in Western blots. Presentation of the foreign epitope on the surface of recombinant OBs was demonstrated by specific immunoprecipitation of the anti-influenza mAb with recombinant OBs. The recombinant polyhedrin-influenza epitope fusion protein stimulated an influenza-specific immune response in rabbits.
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Affiliation(s)
- J H McLinden
- American Biogenetic Sciences Inc., University of Notre Dame, Indiana 46556
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25
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Winokur PL, McLinden JH, Stapleton JT. The hepatitis A virus polyprotein expressed by a recombinant vaccinia virus undergoes proteolytic processing and assembly into viruslike particles. J Virol 1991; 65:5029-36. [PMID: 1651421 PMCID: PMC248966 DOI: 10.1128/jvi.65.9.5029-5036.1991] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Hepatitis A virus (HAV) contains a single-stranded, plus-sense RNA genome with a single long open reading frame encoding a polyprotein of approximately 250 kDa. Viral structural proteins are generated by posttranslational proteolytic processing of this polyprotein. We constructed recombinant vaccinia viruses which expressed the HAV polyprotein (rV-ORF) and the P1 structural region (rV-P1). rV-ORF-infected cell lysates demonstrated that the polyprotein was cleaved into immunoreactive 29- and 33-kDa proteins which comigrated with HAV capsid proteins VP0 and VP1. The rV-P1 construct produced a 90-kDa protein which showed no evidence of posttranslational processing. Solid-phase radioimmunoassays with human polyclonal anti-HAV sera and with murine or human neutralizing monoclonal anti-HAV antibodies recognized the rV-ORF-infected cell lysates. Sucrose density gradients of rV-ORF-infected cell lysates contained peaks of HAV antigen with sedimentation coefficients of approximately 70S and 15S, similar to those of HAV empty capsids and pentamers. Immune electron microscopy also demonstrated the presence of viruslike particles in rV-ORF-infected cell lysates. Thus, the HAV polyprotein expressed by a recombinant vaccinia virus demonstrated posttranslational processing into mature capsid proteins which assembled into antigenic viruslike particles.
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Affiliation(s)
- P L Winokur
- Department of Internal Medicine, University of Iowa College of Medicine, Iowa City
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26
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McLinden JH, Sabourin JR, Clark BD, Gensler DR, Workman WE, Dean DH. Cloning and Expression of an Insecticidal k-73 Type Crystal Protein Gene from
Bacillus thuringiensis
var.
kurstaki
into
Escherichia coli. Appl Environ Microbiol 1985; 50:623-8. [PMID: 16346882 PMCID: PMC238679 DOI: 10.1128/aem.50.3.623-628.1985] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A 75-kilobase plasmid from
Bacillus thuringiensis
var.
kurstaki
(HD-244) was associated with the k-73 type insecticidal crystal protein production by mating into
B. cereus
and subsequent curing of excess plasmids. This plasmid was partially digested with endonuclease R ·
Sau
3A and the fragments were cloned into
Escherichia coli
(HB101) on vector pBR322. Candidate clones were screened for plasmid vectors which contained the expected insert size (at least 3 kilobases) and then with an enzyme-linked immunosorbent assay, using antisera prepared against electrophoretically purified, solubilized insecticidal crystal protein of 130,000 daltons. Several positive clones were isolated and were analyzed for expression, toxicity, and genetic content by restriction enzyme analysis. Electrophoretic transfer blots of proteins from a candidate
E. coli
clone, analyzed by enzyme-linked immunosorbent assay, demonstrated a predominant cross-reacting protein of about 140,000 daltons. Ouchterlony analysis also showed a single precipitin band. Extensive bioassays with
Manduca sexta
larvae revealed that the
E. coli
clones make toxin with a specific activity (50% lethal dose per microgram of cross-reacting protein) equivalent to that of the parental
B. thuringiensis
strain or a
B. cereus
trancipient carrying the toxin-encoding, 75-kilobase plasmid.
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Affiliation(s)
- J H McLinden
- Department of Microbiology, The Ohio State University, Columbus, Ohio 43210
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27
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McLinden JH, Wong KP, Murdock AL, Amelunxen RE. Conformational studies on the inactivation of glyceraldehyde-3-phosphate dehydrogenase from the facultative thermophile Bacillus coagulans KU. Arch Biochem Biophys 1984; 233:299-309. [PMID: 6465902 DOI: 10.1016/0003-9861(84)90629-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Among the various proposals that have been made in attempting to explain the ability of thermophiles to reproduce at high temperatures, there is no doubt that obligate and extreme thermophiles synthesize proteins (and other molecules) that have sufficient intrinsic molecular stability to withstand increased thermal stress. In contrast, the glyceraldehyde-3-phosphate dehydrogenase from the facultative thermophile Bacillus coagulans KU has been shown to be quite thermolabile in vitro. Thermal inactivation is not due to loss of bound NAD+. It has also been shown that the enzymatic activity can be thermostabilized in vitro by increased ionic strength. As previously reported [J. W. Crabb, A. L. Murdock, and R. E. Amelunxen (1975) Biochem. Biophys. Res. Commun. 62, 627; (1977) Biochemistry 16, 4840], the enzyme loses 94-97% of enzymatic activity after heat treatment at 55 degrees C for 5 min in 0.05 M sodium phosphate buffer (pH 7.1); however, by increasing the ionic strength to 1.8, complete protection was conferred at this temperature. Gel-filtration chromatography has been used to study the initial dissociation and subsequent aggregation of the glyceraldehyde-3-phosphate dehydrogenase after thermal inactivation. Aggregation occurs when the enzyme is heated at 50 degrees or 55 degrees C. Loss of enzymatic activity is correlated with changes in the tertiary structure as measured by the near-uv CD spectrum of the enzyme following heat inactivation, with essential disappearance of the peaks at 263 and 296 nm, and a blue shift of the far-uv spectrum, which is a measure of secondary structure. Estimation of secondary structure of the unheated protein from the far-uv CD data showed the enzyme contains approximately 26% alpha-helix, approximately 21% beta-structure, and approximately 53% disordered structure. Heat treatment at various temperatures resulted in only slight changes of the estimated secondary structure. Increased ionic strength prevents thermal alteration of the CD spectrum in both near- and far-uv regions. The data support the previous proposal that thermolabile enzymes such as the glyceraldehyde-3-phosphate dehydrogenase from the facultative thermophile B. coagulans are thermostabilized in vivo mainly by the intracellular charged macromolecular environment.
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Crabb JW, Murdock AL, Suzuki T, Hamilton JW, McLinden JH, Amelunxen RE. Sequence homology in the amino-terminal and active-site regions of thermolabile glyceraldehyde-3-phosphate dehydrogenase from a thermophile. J Bacteriol 1981; 145:503-12. [PMID: 7462149 PMCID: PMC217300 DOI: 10.1128/jb.145.1.503-512.1981] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The unusual thermolability of glyceraldehyde-3-phosphate dehydrogenase from the facultative thermophile Bacillus coagulans KU (Crabb et al., Biochemistry 16:4840-4847, 1977) has provided the first opportunity to study a homologous enzyme from the same genus that exhibits a marked difference in thermostability. In pursuit of the structural bases for the thermostability of proteins, the sequences of the amino terminus (residues 1 through 27) and the active-site cysteine cyanogen bromide peptide (residues 130 through 167) of this enzyme have been determined and compared with sequences of the enzyme from other sources. The importance of comparing phylogenetically related proteins is evident from the 87% identity found between these sequences in the enzyme from B. coagulans and Bacillus stearothermophilus, versus only 45% identity for all other known sequences. The marked sequence identity of the enzyme from the two Bacillus species drew attention to the variable region (residues 138 through 140a) which is exposed to the exterior of the quaternary structure of this enzyme. Based on the reported crystallographic structures of the enzyme from lobster muscle and B. stearothermophilus and space-filling models of the variable region, the segment Asp-Pro-Lys-Ala in B. stearothermophilus should be more thermostable than the analogous sequence, Asp-Ala-Ala-Asn, from B. coagulans. In addition, the space-filling models suggested that the spatial relationship of an amino acid side chain and its potential for close packing and interactions with neighboring side chains may be more important than the type of amino acid substituted.
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