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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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2
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Frey SE, Stapleton JT, Ballas ZK, Rasmussen WL, Kaufman TM, Blevins TP, Jensen TL, Davies DH, Tary-Lehmann M, Chaplin P, Hill H, Goll JB. Human Antibody Responses Following Vaccinia Immunization Using Protein Microarrays and Correlation With Cell-Mediated Immunity and Antibody-Dependent Cellular Cytotoxicity Responses. J Infect Dis 2021; 224:1372-1382. [PMID: 33675226 PMCID: PMC8861366 DOI: 10.1093/infdis/jiab111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 10/14/2020] [Accepted: 03/05/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND There are limited data regarding immunological correlates of protection for the modified vaccinia Ankara (MVA) smallpox vaccine. METHODS A total of 523 vaccinia-naive subjects were randomized to receive 2 vaccine doses, as lyophilized MVA given subcutaneously, liquid MVA given subcutaneously (liquid-SC group), or liquid MVA given intradermally (liquid-ID group) 28 days apart. For a subset of subjects, antibody-dependent cellular cytotoxicity (ADCC), interferon-γ release enzyme-linked immunospot (ELISPOT), and protein microarray antibody-binding assays were conducted. Protein microarray responses were assessed for correlations with plaque reduction neutralization titer (PRNT), enzyme-linked immunosorbent assay, ADCC, and ELISPOT results. RESULTS MVA elicited significant microarray antibody responses to 15 of 224 antigens, mostly virion membrane proteins, at day 28 or 42, particularly WR113/D8L and WR101H3L. In the liquid-SC group, responses to 9 antigens, including WR113/D8L and WR101/H3L, correlated with PRNT results. Three were correlated in the liquid-ID group. No significant correlations were observed with ELISPOT responses. In the liquid-ID group, WR052/F13L, a membrane glycoprotein, correlated with ADCC responses. CONCLUSIONS MVA elicited antibodies to 15 vaccinia strain antigens representing virion membrane. Antibody responses to 2 proteins strongly increased and significantly correlated with increases in PRNT. Responses to these proteins are potential correlates of protection and may serve as immunogens for future vaccine development. CLINICAL TRIALS REGISTRATION NCT00914732.
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Affiliation(s)
- Sharon E Frey
- Department of Internal Medicine, Saint Louis University School of Medicine, St Louis, Missouri, USA
| | - Jack T Stapleton
- Department of Internal Medicine, University of Iowa and Iowa City VA Medical Center, Iowa City, Iowa, USA
| | - Zuhair K Ballas
- Department of Internal Medicine, University of Iowa and Iowa City VA Medical Center, Iowa City, Iowa, USA
| | - Wendy L Rasmussen
- Department of Internal Medicine, University of Iowa and Iowa City VA Medical Center, Iowa City, Iowa, USA
| | - Thomas M Kaufman
- Department of Internal Medicine, University of Iowa and Iowa City VA Medical Center, Iowa City, Iowa, USA
| | - Tammy P Blevins
- Department of Internal Medicine, Saint Louis University School of Medicine, St Louis, Missouri, USA
| | | | - D Huw Davies
- Vaccine Research & Development Center, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California, USA
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3
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Welch JL, Kaufman TM, Stapleton JT, Okeoma CM. Semen exosomes inhibit HIV infection and HIV-induced proinflammatory cytokine production independent of the activation state of primary lymphocytes. FEBS Lett 2019; 594:695-709. [PMID: 31665815 DOI: 10.1002/1873-3468.13653] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [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: 09/07/2019] [Revised: 10/09/2019] [Accepted: 10/23/2019] [Indexed: 12/15/2022]
Abstract
Semen exosomes (SE) inhibit HIV infection. However, the effect of SE on cell activation and inflammation remains unknown. We characterized the response of peripheral blood mononuclear cells (PBMCs) from HIV-uninfected and antiretroviral therapy-suppressed HIV-infected (HIV+) subjects to SE. Quiescent PBMCs or T-cell receptor (TCR)-activated PBMCs from HIV- and HIV+ donors were stimulated with SE in the presence/absence of ex vivo HIV infection. In HIV-infected PBMCs, SE did not reactivate HIV, did not induce lymphoblast development, nor increase CD69+/CD25+ numbers. Furthermore, SE inhibited de novo HIV infection without altering cell activation. SE also asynchronously downregulated HIV-inducible IL1β, IL8, and TNFα and upregulated CXCL10. These data suggest that SE inhibits HIV infection and production of HIV-induced proinflammatory cytokines while preserving lymphocyte activation.
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Affiliation(s)
- Jennifer L Welch
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Medical Service, Iowa City Veterans Affairs Medical Center, IA, USA
| | - Thomas M Kaufman
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Medical Service, Iowa City Veterans Affairs Medical Center, IA, USA
| | - Jack T Stapleton
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.,Medical Service, Iowa City Veterans Affairs Medical Center, IA, USA
| | - Chioma M Okeoma
- Department of Pharmacology, Stony Brook University Renaissance School of Medicine, NY, USA
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4
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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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5
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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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6
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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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7
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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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8
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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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9
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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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10
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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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11
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Torrelles JB, DesJardin LE, MacNeil J, Kaufman TM, Kutzbach B, Knaup R, McCarthy TR, Gurcha SS, Besra GS, Clegg S, Schlesinger LS. Inactivation of Mycobacterium tuberculosis mannosyltransferase pimB reduces the cell wall lipoarabinomannan and lipomannan content and increases the rate of bacterial-induced human macrophage cell death. Glycobiology 2009; 19:743-55. [PMID: 19318518 DOI: 10.1093/glycob/cwp042] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The Mycobacterium tuberculosis (M.tb) cell wall contains an important group of structurally related mannosylated lipoglycans called phosphatidyl-myo-inositol mannosides (PIMs), lipomannan (LM), and mannose-capped lipoarabinomannan (ManLAM), where the terminal alpha-[1-->2] mannosyl structures on higher order PIMs and ManLAM have been shown to engage C-type lectins such as the macrophage mannose receptor directing M.tb phagosome maturation arrest. An important gene described in the biosynthesis of these molecules is the mannosyltransferase pimB (Rv0557). Here, we disrupted pimB in a virulent strain of M.tb. We demonstrate that the inactivation of pimB in M.tb does not abolish the production of any of its cell wall mannosylated lipoglycans; however, it results in a quantitative decrease in the ManLAM and LM content without affecting higher order PIMs. This finding indicates gene redundancy or the possibility of an alternative biosynthetic pathway that may compensate for the PimB deficiency. Furthermore, infection of human macrophages by the pimB mutant leads to an alteration in macrophage phenotype concomitant with a significant increase in the rate of macrophage death.
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Affiliation(s)
- Jordi B Torrelles
- Division of Infectious Diseases, Department of Medicine, The Center for Microbial Interface Biology, The Ohio State University, Columbus, OH 43210, USA
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12
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Torrelles JB, Knaup R, Kolareth A, Slepushkina T, Kaufman TM, Kang P, Hill PJ, Brennan PJ, Chatterjee D, Belisle JT, Musser JM, Schlesinger LS. Identification of Mycobacterium tuberculosis clinical isolates with altered phagocytosis by human macrophages due to a truncated lipoarabinomannan. J Biol Chem 2008; 283:31417-28. [PMID: 18784076 DOI: 10.1074/jbc.m806350200] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phenotypically distinct clinical isolates of Mycobacterium tuberculosis are capable of altering the balance that exists between the pathogen and human host and ultimately the outcome of infection. This study has identified two M. tuberculosis strains (i.e. HN885 and HN1554) among a bank of clinical isolates with a striking defect in phagocytosis by primary human macrophages when compared with strain Erdman, a commonly used laboratory strain for studies of pathogenesis. Mass spectrometry in conjunction with NMR studies unequivocally confirmed that both HN885 and HN1554 contain truncated and more branched forms of mannose-capped lipoarabinomannan (ManLAM) with a marked reduction of their linear arabinan (corresponding mainly to the inner Araf-alpha(1-->5)-Araf unit) and mannan (with fewer 6-Manp residues and more substitutions in the linear Manp-alpha(1-->6)-Manp unit) domains. The truncation in the ManLAM molecules produced by strains HN885 and HN1554 led to a significant reduction in their surface availability. In addition, there was a marked reduction of higher order phosphatidyl-myo-inositol mannosides and the presence of dimycocerosates, triglycerides, and phenolic glycolipid in their cell envelope. Less exposed ManLAM and reduced higher order phosphatidyl-myo-inositol mannosides in strains HN885 and HN1554 resulted in their low association with the macrophage mannose receptor. Despite reduced phagocytosis, ingested bacilli replicated at a fast rate following serum opsonization. Our results provide evidence that the clinical spectrum of tuberculosis may be dictated not only by the host but also by the amounts and ratios of surface exposed mycobacterial adherence factors defined by strain genotype.
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Affiliation(s)
- Jordi B Torrelles
- Center for Microbial Interface Biology, Division of Infectious Diseases, Department of Internal Medicine, Ohio State University, Columbus, Ohio 43210, USA
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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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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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15
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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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16
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Kang PB, Azad AK, Torrelles JB, Kaufman TM, Beharka A, Tibesar E, DesJardin LE, Schlesinger LS. The human macrophage mannose receptor directs Mycobacterium tuberculosis lipoarabinomannan-mediated phagosome biogenesis. ACTA ACUST UNITED AC 2006; 202:987-99. [PMID: 16203868 PMCID: PMC2213176 DOI: 10.1084/jem.20051239] [Citation(s) in RCA: 364] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Mycobacterium tuberculosis (M.tb) survives in macrophages in part by limiting phagosome–lysosome (P-L) fusion. M.tb mannose-capped lipoarabinomannan (ManLAM) blocks phagosome maturation. The pattern recognition mannose receptor (MR) binds to the ManLAM mannose caps and mediates phagocytosis of bacilli by human macrophages. Using quantitative electron and confocal microscopy, we report that engagement of the MR by ManLAM during the phagocytic process is a key step in limiting P-L fusion. P-L fusion of ManLAM microspheres was significantly reduced in human macrophages and an MR-expressing cell line but not in monocytes that lack the receptor. Moreover, reversal of P-L fusion inhibition occurred with MR blockade. Inhibition of P-L fusion did not occur with entry via Fcγ receptors or dendritic cell–specific intracellular adhesion molecule 3 grabbing nonintegrin, or with phosphatidylinositol-capped lipoarabinomannan. The ManLAM mannose cap structures were necessary in limiting P-L fusion, and the intact molecule was required to maintain this phenotype. Finally, MR blockade during phagocytosis of virulent M.tb led to a reversal of P-L fusion inhibition in human macrophages (84.0 ± 5.1% vs. 38.6 ± 0.6%). Thus, engagement of the MR by ManLAM during the phagocytic process directs M.tb to its initial phagosomal niche, thereby enhancing survival in human macrophages.
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Affiliation(s)
- Peter B Kang
- Division of Infectious Diseases, Department of Internal Medicine, Center for Microbial Interface Biology, The Ohio State University, Columbus, OH 43210, USA
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DesJardin LE, Kaufman TM, Potts B, Kutzbach B, Yi H, Schlesinger LS. Mycobacterium tuberculosis-infected human macrophages exhibit enhanced cellular adhesion with increased expression of LFA-1 and ICAM-1 and reduced expression and/or function of complement receptors, FcgammaRII and the mannose receptor. Microbiology (Reading) 2002; 148:3161-3171. [PMID: 12368450 DOI: 10.1099/00221287-148-10-3161] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The entry of Mycobacterium tuberculosis (Mtb) into the host macrophage and its survival in this environment are key components of tuberculosis pathogenesis. Following intracellular replication of the bacterium within alveolar macrophages, there is spread of bacilli to regional lymph nodes in the lungs and subsequent presentation of antigens to the host immune system. How this process occurs remains poorly understood, but one mechanism may involve the migration of macrophages containing Mtb across the alveoli to lymph nodes, where there is development of a protective host response with formation of granulomas composed in part of aggregated and fused, apoptotic, infected macrophages. Leukocyte integrins, including lymphocyte function-associated antigen-1 (LFA-1) and complement receptors CR3 and CR4, and their counter receptors play a major role in macrophage adhesion processes and phagocytosis. In this study, the appearance of Mtb-infected macrophages over time was examined, using inverted-phase microscopy and an in vitro culture model of human monocyte-derived macrophages (MDMs). Prior to and immediately following infection of the MDMs with Mtb, the macrophages appeared as individual cells in monolayer culture; however, within 24 h of infection with Mtb, the MDMs began to migrate and adhere to each other. The kinetics of this response were dependent on both the m.o.i. and the length of infection. Quantitative transmission electron microscopy studies revealed that macrophage adhesion was accompanied by increases in levels of LFA-1 and its counter receptor (ICAM-1), decreases in surface levels of the phagocytic receptors CR3, CR4 and FcgammaRII, and an increase in major histocompatibility complex Class II (MHC-II) molecules at 72 h post-infection. Decreases in surface levels of CR3 and CR4 had a functional correlate, with macrophages containing live bacilli showing a diminished phagocytic capacity for complement-opsonized sheep erythrocytes; macrophages containing heat-killed bacilli did not show this diminished capacity. The modulation of macrophage adhesion and phagocytic proteins may influence the trafficking of Mtb-infected macrophages within the host, with increases in levels of LFA-1 and ICAM-1 enhancing the adhesive properties of the macrophage and decreases in phagocytic receptors diminishing the phagocytic capacity of an already-infected cell, potentially allowing for maintenance of the intracellular niche of Mtb.
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Affiliation(s)
- Lucy E DesJardin
- Veterans Admin. Med. Center1 and Depts of Medicine2, Microbiology3 and the Interdisciplinary Immunology Program4, University of Iowa, Iowa City, IA, USA
| | - Thomas M Kaufman
- Veterans Admin. Med. Center1 and Depts of Medicine2, Microbiology3 and the Interdisciplinary Immunology Program4, University of Iowa, Iowa City, IA, USA
| | - Brian Potts
- Veterans Admin. Med. Center1 and Depts of Medicine2, Microbiology3 and the Interdisciplinary Immunology Program4, University of Iowa, Iowa City, IA, USA
| | - Beth Kutzbach
- Veterans Admin. Med. Center1 and Depts of Medicine2, Microbiology3 and the Interdisciplinary Immunology Program4, University of Iowa, Iowa City, IA, USA
| | - Hong Yi
- Veterans Admin. Med. Center1 and Depts of Medicine2, Microbiology3 and the Interdisciplinary Immunology Program4, University of Iowa, Iowa City, IA, USA
| | - Larry S Schlesinger
- Veterans Admin. Med. Center1 and Depts of Medicine2, Microbiology3 and the Interdisciplinary Immunology Program4, University of Iowa, Iowa City, IA, USA
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18
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Kaufman TM. Weight Room Considerations for the Throwing Athlete. Strength Cond J 1999. [DOI: 10.1519/00126548-199908000-00001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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19
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Schlesinger LS, Kaufman TM, Iyer S, Hull SR, Marchiando LK. Differences in mannose receptor-mediated uptake of lipoarabinomannan from virulent and attenuated strains of Mycobacterium tuberculosis by human macrophages. J Immunol 1996; 157:4568-75. [PMID: 8906835] [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: 02/03/2023]
Abstract
Phagocytosis of the virulent Erdman and H37Rv strains of Mycobacterium tuberculosis, but not that of the attenuated H37Ra strain, by human macrophages is mediated by the mannose receptor (MR) in addition to complement receptors. We have recently determined that a major capsular lipoglycan, lipoarabinomannan (LAM), from the Erdman strain serves as a ligand for the MR during phagocytosis of bacteria. In this study we directly compare uptake of Erdman, H37Rv, and H37Ra LAM by human macrophages and assess the relative contribution of the MR in this process. Microspheres coated with LAM served as model phagocytic particles for studies of LAM as a capsular ligand. Uptake (37 degrees C) of LAM microspheres by monocyte-derived macrophages was greatest for Erdman LAM and intermediate for H37Rv and H37Ra LAM compared with that of buffer microspheres or microspheres coated with LAM from a nontuberculosis strain of mycobacterium (AraLAM). Inhibition of microsphere uptake in the presence of mannan or mannose-BSA was highest for Erdman LAM (75 +/- 8 and 50 +/- 7%, respectively) and H37Rv LAM (57 +/- 13 and 21 +/- 5%, respectively) relative to H37Ra LAM (36 +/- 16 and 22 +/- 11 %, respectively). Inhibition of microsphere uptake in the presence of anti-MR Ab followed a similar pattern: Erdman LAM (80 +/- 9%) > H37Rv LAM (53 +/- 1%) > H37Ra LAM (26 +/- 12%). Attachment (4 degrees C) of microspheres coated with Erdman LAM, H37Rv LAM, and H37Ra LAM was enhanced 12-, 5-, and 4-fold, respectively, compared with that of microspheres coated with AraLAM, and mannose-BSA inhibited attachment of these microspheres by 82 +/- 7, 69 +/- 8, and 12 +/- 17%. Galactose-BSA did not inhibit attachment of any LAM microsphere groups. Chromatographic analyses of mild acid hydrolysates of LAM from Erdman, H37Rv, and H37Ra all revealed the major terminal dimannosyl units. These studies demonstrate differences in the ability of LAM from different M. tuberculosis strains to mediate adherence to macrophages and to serve as ligands for the macrophage MR despite the presence of terminal dimannosyl units. Thus, these studies point toward other subtle structural alterations in LAM among strains that influence initial interactions with human phagocytes.
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Affiliation(s)
- L S Schlesinger
- Department of Medicine, Department of Veterans Affairs Medical Center, University of Iowa, Iowa City 52242, USA
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20
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Schlesinger LS, Kaufman TM, Iyer S, Hull SR, Marchiando LK. Differences in mannose receptor-mediated uptake of lipoarabinomannan from virulent and attenuated strains of Mycobacterium tuberculosis by human macrophages. The Journal of Immunology 1996. [DOI: 10.4049/jimmunol.157.10.4568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Phagocytosis of the virulent Erdman and H37Rv strains of Mycobacterium tuberculosis, but not that of the attenuated H37Ra strain, by human macrophages is mediated by the mannose receptor (MR) in addition to complement receptors. We have recently determined that a major capsular lipoglycan, lipoarabinomannan (LAM), from the Erdman strain serves as a ligand for the MR during phagocytosis of bacteria. In this study we directly compare uptake of Erdman, H37Rv, and H37Ra LAM by human macrophages and assess the relative contribution of the MR in this process. Microspheres coated with LAM served as model phagocytic particles for studies of LAM as a capsular ligand. Uptake (37 degrees C) of LAM microspheres by monocyte-derived macrophages was greatest for Erdman LAM and intermediate for H37Rv and H37Ra LAM compared with that of buffer microspheres or microspheres coated with LAM from a nontuberculosis strain of mycobacterium (AraLAM). Inhibition of microsphere uptake in the presence of mannan or mannose-BSA was highest for Erdman LAM (75 +/- 8 and 50 +/- 7%, respectively) and H37Rv LAM (57 +/- 13 and 21 +/- 5%, respectively) relative to H37Ra LAM (36 +/- 16 and 22 +/- 11 %, respectively). Inhibition of microsphere uptake in the presence of anti-MR Ab followed a similar pattern: Erdman LAM (80 +/- 9%) > H37Rv LAM (53 +/- 1%) > H37Ra LAM (26 +/- 12%). Attachment (4 degrees C) of microspheres coated with Erdman LAM, H37Rv LAM, and H37Ra LAM was enhanced 12-, 5-, and 4-fold, respectively, compared with that of microspheres coated with AraLAM, and mannose-BSA inhibited attachment of these microspheres by 82 +/- 7, 69 +/- 8, and 12 +/- 17%. Galactose-BSA did not inhibit attachment of any LAM microsphere groups. Chromatographic analyses of mild acid hydrolysates of LAM from Erdman, H37Rv, and H37Ra all revealed the major terminal dimannosyl units. These studies demonstrate differences in the ability of LAM from different M. tuberculosis strains to mediate adherence to macrophages and to serve as ligands for the macrophage MR despite the presence of terminal dimannosyl units. Thus, these studies point toward other subtle structural alterations in LAM among strains that influence initial interactions with human phagocytes.
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Affiliation(s)
- L S Schlesinger
- Department of Medicine, Department of Veterans Affairs Medical Center, University of Iowa, Iowa City 52242, USA
| | - T M Kaufman
- Department of Medicine, Department of Veterans Affairs Medical Center, University of Iowa, Iowa City 52242, USA
| | - S Iyer
- Department of Medicine, Department of Veterans Affairs Medical Center, University of Iowa, Iowa City 52242, USA
| | - S R Hull
- Department of Medicine, Department of Veterans Affairs Medical Center, University of Iowa, Iowa City 52242, USA
| | - L K Marchiando
- Department of Medicine, Department of Veterans Affairs Medical Center, University of Iowa, Iowa City 52242, USA
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21
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Schlesinger LS, Hull SR, Kaufman TM. Binding of the terminal mannosyl units of lipoarabinomannan from a virulent strain of Mycobacterium tuberculosis to human macrophages. The Journal of Immunology 1994. [DOI: 10.4049/jimmunol.152.8.4070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Recent studies from this laboratory have demonstrated that macrophage phagocytosis of virulent strains (Erdman and H37Rv), but not the attenuated H37Ra strain of Mycobacterium tuberculosis, is mediated by phagocyte mannose receptors (MR) in addition to complement receptors (CR1 and the leukocyte integrins CR3 and CR4). Lipoarabinomannan (LAM) is a major surface lipoglycan of M. tuberculosis. LAM from the Erdman strain (Man-LAM) contains mannose oligosaccharides at the terminal portions of the molecule. This study investigated the ability of ManLAM to serve as a microbial ligand in adherence to human monocyte-derived macrophages (MDM). Polystyrene microspheres were coated with known amounts of purified ManLAM, LAM without the terminal mannosyl units from an avirulent mycobacterium (AraLAM), lipomannan (LM), or buffer and incubated with MDM monolayers in the absence of serum. The presence of LAM on microspheres was confirmed by indirect immunofluorescence studies. Microspheres coated with ManLAM demonstrated a more than threefold increase in adherence to MDM when compared with microspheres coated with AraLAM, LM, or buffer and the low levels of adherence of microspheres in the latter three groups were comparable. Compared with control monolayers, selective down-modulation of MDM MR on a mannan substrate abrogated the enhanced adherence of microspheres mediated by ManLAM. Adherence of microspheres coated with AraLAM, LM, or buffer was not influenced by MR modulation. To confirm the importance of the terminal mannosyl units of ManLAM in the enhanced adherence of ManLAM microspheres to MDM, these units were selectively removed by exomannosidase treatment. The structure of LAM products before and after enzyme treatment was confirmed by high performance anion exchange chromatography with pulsed amperometric detection. Removal of the terminal mannosyl units abolished the capacity of ManLAM to mediate enhanced adherence of microspheres to MDM. Finally, preincubation of Erdman M. tuberculosis with CS-40, a mAb directed against LAM, resulted in a consistent inhibition of adherence of the bacteria to MDM (up to 49% inhibition), confirming a role for ManLAM on intact bacteria in adherence to MDM. Thus, we provide evidence for a novel receptor-ligand pathway in phagocytosis of M. tuberculosis that consists of MR on macrophages and mannosyl units at the terminal end of ManLAM, a major microbial surface lipoglycan.
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Affiliation(s)
- L S Schlesinger
- Department of Medicine, Department of Veterans Affairs Medical Center, Iowa City, IA
| | - S R Hull
- Department of Medicine, Department of Veterans Affairs Medical Center, Iowa City, IA
| | - T M Kaufman
- Department of Medicine, Department of Veterans Affairs Medical Center, Iowa City, IA
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Schlesinger LS, Hull SR, Kaufman TM. Binding of the terminal mannosyl units of lipoarabinomannan from a virulent strain of Mycobacterium tuberculosis to human macrophages. J Immunol 1994; 152:4070-9. [PMID: 8144972] [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: 01/29/2023]
Abstract
Recent studies from this laboratory have demonstrated that macrophage phagocytosis of virulent strains (Erdman and H37Rv), but not the attenuated H37Ra strain of Mycobacterium tuberculosis, is mediated by phagocyte mannose receptors (MR) in addition to complement receptors (CR1 and the leukocyte integrins CR3 and CR4). Lipoarabinomannan (LAM) is a major surface lipoglycan of M. tuberculosis. LAM from the Erdman strain (Man-LAM) contains mannose oligosaccharides at the terminal portions of the molecule. This study investigated the ability of ManLAM to serve as a microbial ligand in adherence to human monocyte-derived macrophages (MDM). Polystyrene microspheres were coated with known amounts of purified ManLAM, LAM without the terminal mannosyl units from an avirulent mycobacterium (AraLAM), lipomannan (LM), or buffer and incubated with MDM monolayers in the absence of serum. The presence of LAM on microspheres was confirmed by indirect immunofluorescence studies. Microspheres coated with ManLAM demonstrated a more than threefold increase in adherence to MDM when compared with microspheres coated with AraLAM, LM, or buffer and the low levels of adherence of microspheres in the latter three groups were comparable. Compared with control monolayers, selective down-modulation of MDM MR on a mannan substrate abrogated the enhanced adherence of microspheres mediated by ManLAM. Adherence of microspheres coated with AraLAM, LM, or buffer was not influenced by MR modulation. To confirm the importance of the terminal mannosyl units of ManLAM in the enhanced adherence of ManLAM microspheres to MDM, these units were selectively removed by exomannosidase treatment. The structure of LAM products before and after enzyme treatment was confirmed by high performance anion exchange chromatography with pulsed amperometric detection. Removal of the terminal mannosyl units abolished the capacity of ManLAM to mediate enhanced adherence of microspheres to MDM. Finally, preincubation of Erdman M. tuberculosis with CS-40, a mAb directed against LAM, resulted in a consistent inhibition of adherence of the bacteria to MDM (up to 49% inhibition), confirming a role for ManLAM on intact bacteria in adherence to MDM. Thus, we provide evidence for a novel receptor-ligand pathway in phagocytosis of M. tuberculosis that consists of MR on macrophages and mannosyl units at the terminal end of ManLAM, a major microbial surface lipoglycan.
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Affiliation(s)
- L S Schlesinger
- Department of Medicine, Department of Veterans Affairs Medical Center, Iowa City, IA
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23
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Kaufman TM, Horton JW. Characterization of cardiac beta-adrenergic receptors in the guinea pig heart: application to study of beta-adrenergic receptors in shock models. J Surg Res 1993; 55:516-23. [PMID: 8231171 DOI: 10.1006/jsre.1993.1177] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [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: 01/29/2023]
Abstract
The myocardial response to catecholamines is significantly diminished in many types of shock or heart failure. The guinea pig heart is an ideal model for the study of shock, as it is relatively inexpensive, and the cardiovascular system of the guinea pig most closely resembles that of the human. Using this model, we have developed techniques to characterize and quantitate changes in beta-adrenergic receptors (beta AR) in the guinea pig heart after burn injury. Preliminary experiments were performed to determine the optimum binding conditions, e.g., incubation time and conditions, protein concentrations, rinsing, etc. Additional experiments were conducted using agonists and antagonists to characterize the rank order of potency and stereospecificity of the beta AR. Crude membrane preparations (50 micrograms/250 microliters) from sham-burned and burned hearts were incubated with 8-10 concentrations of 125I-cyanopindolol (10-450 pM) at 37 degrees C for 1 hr. Under these conditions, binding assays were linear with respect to protein concentration and time. Alprenolol (10 microM) was used to determine nonspecific binding. The membrane preparations used in this study bound both agonists and antagonists with a rank order of potency and stereospecificity characteristic of a beta-adrenergic receptor. Finally, agonist competition curves were performed with isoproterenol in the presence and absence of Gpp(NH)p to determine receptor regulation by the Gs protein. Analysis using computer-assisted techniques suggests that the fraction of high-affinity beta-receptors is significantly reduced after burn injury (41.2 +/- 4.7%) compared to sham-burned controls (54 +/- 2%, P < or = 0.023).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T M Kaufman
- Department of Surgery, University of Texas Southwestern Medical Center, Dallas 75235-9031
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24
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Abstract
Cardiac dysfunction occurs after a major burn injury regardless of age; whether burn trauma causes greater myocardial contractile depression in the older subject due to reduced cardiac reserves that normally occur with adult aging is not known. The cellular basis for burn-induced cardiac dysfunction is not known, but several studies have suggested that alterations occur in the rate of Ca2+ delivery to the contractile proteins as well as in the rate of Ca2+ removal from the sarcoplasm by the sarcoplasmic reticulum (SR). To determine if age-related differences in the cardiac contractile response to burn injury are associated with differences in SR Ca2+ transport, an isolated heart preparation was used to examine mechanical function, and myocardial homogenate preparations were used to assess SR Ca2+ transport. Guinea pigs from both age groups (adult, 6-8 months, and senescent, 34-36 months of age) were divided into two subgroups--control and 45% cutaneous scald burn. Cardiac dysfunction associated with adult aging alone was indicated by lower systolic pressure and lower rates of left ventricular (LV) pressure rise and fall, as well as decreased responses to isoproterenol, exogenous Ca2+, increased coronary flow rate, and electrical pacing. Myocardial depression in senescent control hearts was accompanied by a decreased maximal Ca2+ uptake in myocardial homogenates, suggesting that altered SR calcium transport may contribute to the diminished contractile function associated with aging. Burn injury impaired cardiac function in all animals regardless of age as evidenced by a leftward shift of LV function curves and altered responses to receptor- and nonreceptor-mediated inotropic interventions. However, the percentage change in cardiac function after burn injury was similar in both age groups compared to those of their respective controls. Significant alterations in SR Ca2+ transport were observed in myocardial homogenates isolated from both adult and senescent hearts after burn injury. Our data confirm that burn injury induced cardiac contractile dysfunction as well as alterations in SR Ca2+ transport function regardless of age, and we conclude that altered SR Ca2+ transport function contributes, in part, to the diminished cardiac function after burn injury.
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Affiliation(s)
- J W Horton
- Department of Surgery, University of Texas Southwestern Medical Center, Dallas 75235
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25
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Abstract
Previous studies in our laboratory have demonstrated that burn injury (45% total body surface area, 3rd-degree scald burn) diminishes contractile and relaxation function in the isolated perfused guinea pig heart. The mechanisms responsible for the burn-mediated dysfunction are not well understood. Therefore the purpose of this study was to examine the inotropic response to isoproterenol, a beta-adrenergic agonist, and burn-induced alterations in beta-adrenergic receptors (beta-AR) in adult guinea pig hearts. Isoproterenol dose-response curves were generated in isolated perfused hearts from sham-burned and burned guinea pigs. In addition, binding studies were performed using [125I]iodocyanopindolol on hearts from sham-burned and burned guinea pigs. Both the functional response and sensitivity to isoproterenol were significantly diminished 24 h after burn injury. beta-AR density (binding capacity, Bmax) and affinity were determined by Scatchard analysis. Agonist competition curves were performed in the presence or absence of 0.1 mM 5'-guanylyl imidodiphosphate. There was no difference in Bmax in membranes from sham-burned and burned hearts; however, the affinity of beta-AR was significantly decreased after burn injury compared with sham burn [dissociation constant = 32.5 +/- 1.9 (mean +/- SE), n = 10, vs. 26.7 +/- 1.7 pM, n = 10, P = 0.039]. Furthermore, the fraction of receptors in a high-affinity state (those functionally coupled to Gs protein) was significantly decreased after burn injury compared with sham burn (41.2 +/- 4.7%, n = 9, vs. 54 +/- 2%, n = 9, P = 0.023).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T M Kaufman
- Department of Surgery, University of Texas Southwestern Medical Center, Dallas 75235-9031
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26
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Abstract
Rapid regulation of relaxation is essential to allow the heart to alter stroke volume in response to stress. Inasmuch as Ca2+ transport by the sarcoplasmic reticulum (SR) is an important determinant of relaxation, the purpose of this study was to examine developmental differences in the ability of isoproterenol to alter relaxation time and to determine if these differences were associated with age-related changes in Ca2+ transport by the SR in isolated, perfused adult and newborn guinea pig hearts. Control values of the time constant of isovolumic relaxation (tau) were 37.8 +/- 5.9 ms in adult hearts (n = 8) and 31.6 +/- 5.3 ms in newborn hearts (n = 6). With maximum isoproterenol stimulation, the decrease in tau was significantly greater in adult (51.1 +/- 8.8%, mean +/- SD) compared with that in newborn (26.3 +/- 3.1%, P less than or equal to 0.0001) hearts. Ca2+ uptake, Ca2(+)-dependent adenosinetriphosphatase activity, and Ca2+ pump density were all significantly greater in SR vesicles isolated from adult hearts compared with values measured in SR vesicles from newborn hearts. We conclude that developmental differences in the capacity of the SR to sequester Ca2+ may contribute to age-related differences in the functional response of the heart to isoproterenol.
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Affiliation(s)
- T M Kaufman
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas 75235
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