1
|
Okpaise D, Sluis-Cremer N, Rappocciolo G, Rinaldo CR. Cholesterol Metabolism in Antigen-Presenting Cells and HIV-1 Trans-Infection of CD4 + T Cells. Viruses 2023; 15:2347. [PMID: 38140588 PMCID: PMC10747884 DOI: 10.3390/v15122347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 11/28/2023] [Accepted: 11/28/2023] [Indexed: 12/24/2023] Open
Abstract
Antiretroviral therapy (ART) provides an effective method for managing HIV-1 infection and preventing the onset of AIDS; however, it is ineffective against the reservoir of latent HIV-1 that persists predominantly in resting CD4+ T cells. Understanding the mechanisms that facilitate the persistence of the latent reservoir is key to developing an effective cure for HIV-1. Of particular importance in the establishment and maintenance of the latent viral reservoir is the intercellular transfer of HIV-1 from professional antigen-presenting cells (APCs-monocytes/macrophages, myeloid dendritic cells, and B lymphocytes) to CD4+ T cells, termed trans-infection. Whereas virus-to-cell HIV-1 cis infection is sensitive to ART, trans-infection is impervious to antiviral therapy. APCs from HIV-1-positive non-progressors (NPs) who control their HIV-1 infection in the absence of ART do not trans-infect CD4+ T cells. In this review, we focus on this unique property of NPs that we propose is driven by a genetically inherited, altered cholesterol metabolism in their APCs. We focus on cellular cholesterol homeostasis and the role of cholesterol metabolism in HIV-1 trans-infection, and notably, the link between cholesterol efflux and HIV-1 trans-infection in NPs.
Collapse
Affiliation(s)
| | | | | | - Charles R. Rinaldo
- Department of Medicine, Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; (D.O.); (N.S.-C.); (G.R.)
| |
Collapse
|
2
|
Oyelade T, Raya RP, Latief K. HIV infection and the implication for COVID‐19 vaccination. PUBLIC HEALTH CHALLENGES 2022. [PMID: 37521727 PMCID: PMC9353425 DOI: 10.1002/puh2.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract Human immunodeficiency virus (HIV) is associated with altered cellular and humoral immune response, especially in patients with an untreated or chronic infection. This may be due to direct and/or indirect HIV viral activities resulting in T‐ and B‐cells dysfunctions. Although still unclear, various studies have proposed that HIV infection may exacerbate the clinical outcomes of COVID‐19. Indeed, COVID‐19 vaccines were developed in record time and have been shown to reduce the severity of COVID‐19 in the general population. These vaccines were also earmarked as a solution to global disruptions caused by the COVID‐19 pandemic. HIV infection has been reported to reduce the efficacy of various other vaccines including those used against Streptococcus pneumoniae, Clostridium tetani, and influenza viruses. However, current guidelines for the administration of available COVID‐19 vaccines do not account for the immune‐compromised state of people living with HIV (PLWH). We discuss here the potentials, nature, and implications of this HIV‐induced dampening of the humoral immune response on COVID‐19 vaccines by first reviewing the literature about efficacy of previous vaccines in PLWH, and then assessing the proportion of PLWH included in phase III clinical trials of the COVID‐19 vaccines currently available. The clinical and public health implications as well as suggestions for governments and non‐governmental organizations are also proposed in the context of whether findings on the safety and efficacy of the vaccines could be extended to PLWH. Impacts The human immunodeficiency virus (HIV) is characterized by attenuated humoral immunity that may reduce the efficacy of vaccines in people living with HIV (PLWH). Vaccination against the SARS‐CoV‐2 infection remains the main public health answer to the COVID‐19 pandemic. Although no significant safety concerns have been raised regarding the COVID‐19 vaccines in PLWH, the efficacy of these vaccines in PLWH has not received due attention. Indeed, phase III clinical trials for the safety and efficacy of COVID‐19 vaccines involved a significantly low number of PLWH. There are major gaps in knowledge on the efficacy of COVID‐19 vaccines in PLWH and until further research is carried out, PLWH should be prioritized along with other at‐risk groups for repeated vaccination and safeguard.
Collapse
Affiliation(s)
- Tope Oyelade
- Institute for Liver and Digestive Health Division of Medicine University College London London UK
| | - Reynie Purnama Raya
- Institute for Global Health Faculty of Population Health Sciences University College London London UK
- Faculty of Science Universitas ‘Aisyiyah Bandung Bandung Indonesia
| | - Kamaluddin Latief
- Global Health and Health Security Department College of Public Health Taipei Medical University Taipei City Taiwan
- Centre for Family Welfare Faculty of Public Health University of Indonesia Depok Indonesia
| |
Collapse
|
3
|
Dhande JR, Bagul RD, Thakar MR. HIV-gp140-Specific Antibodies Generated From Indian Long-Term Non-Progressors Mediate Potent ADCC Activity and Effectively Lyse Reactivated HIV Reservoir. Front Immunol 2022; 13:844610. [PMID: 35309295 PMCID: PMC8924355 DOI: 10.3389/fimmu.2022.844610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/07/2022] [Indexed: 11/13/2022] Open
Abstract
Strategies to reduce the human immunodeficiency virus (HIV) reservoir are urgently required. The antibody-dependent cellular cytotoxicity (ADCC)-mediating anti-HIV antibodies have shown an association with HIV control. We assessed if such antibodies can be generated in vitro and whether the generated antibodies can facilitate the reduction of reactivated HIV reservoir. We isolated HIV-1-gp140-specific memory B cells from HIV-1-infected long-term non-progressors (LTNPs) with or without plasma ADCC and cultured them to generate anti-HIV antibodies. The ability of the generated antibodies to mediate ADCC and facilitate NK cell-mediated lysis of reactivated HIV reservoir was assessed by the rapid fluorometric antibody-dependent cellular cytotoxicity assay and a flow-based novel latency reduction assay, respectively. All LTNPs showed the presence of gp140-specific memory B cells [median: 0.79% (0.54%–1.225%)], which were successfully differentiated into plasma cells [median 72.0% (68.7–82.2%)] in an in-vitro culture and secreted antibodies [median OD: 0.253 (0.205–0.274)]. The HIV-gp140-specific antibodies were generated from 11/13 LTNPs irrespective of their plasma ADCC status. The generated antibodies from LTNPs with plasma ADCC showed higher ADCC potency (median: 37.6%, IQR: 32.95%–51%) and higher reduction in reactivated HIV reservoir (median: 62.5%, IQR: 58.71%–64.92%) as compared with the antibodies generated from LTNPs without plasma ADCC (ADCC: median: 8.85%, IQR: 8%–9.7%; and % p24 reduction median: 13.84, IQR: 9.863%–17.81%). The potency of these antibodies to reduce latent reservoir was two-fold higher than the respective plasma ADCC. The study showed that the potent ADCC-mediating antibodies could be generated from memory B cells of the LTNPs with plasma ADCC activity. These antibodies also showed potent ability to facilitate NK cell-mediated lysis of reactivated HIV reservoirs. It also indicated that memory B cells from individuals with plasma ADCC activity should be preferentially used for such antibody generation. The important role of these antibodies in the reduction of latent reservoirs needs to be further evaluated as a useful strategy to obtain a functional cure for HIV infection.
Collapse
|
4
|
Xie L, Zhang Z, Wang Q, Chen Y, Lu D, Wu W. COVID-19 and Diabetes: A Comprehensive Review of Angiotensin Converting Enzyme 2, Mutual Effects and Pharmacotherapy. Front Endocrinol (Lausanne) 2021; 12:772865. [PMID: 34867819 PMCID: PMC8639866 DOI: 10.3389/fendo.2021.772865] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 10/29/2021] [Indexed: 01/08/2023] Open
Abstract
The potential relationship between diabetes and COVID-19 has been evaluated. However, new knowledge is rapidly emerging. In this study, we systematically reviewed the relationship between viral cell surface receptors (ACE2, AXL, CD147, DC-SIGN, L-SIGN and DPP4) and SARS-CoV-2 infection risk, and emphasized the implications of ACE2 on SARS-CoV-2 infection and COVID-19 pathogenesis. Besides, we updated on the two-way interactions between diabetes and COVID-19, as well as the treatment options for COVID-19 comorbid patients from the perspective of ACE2. The efficacies of various clinical chemotherapeutic options, including anti-diabetic drugs, renin-angiotensin-aldosterone system inhibitors, lipid-lowering drugs, anticoagulants, and glucocorticoids for COVID-19 positive diabetic patients were discussed. Moreover, we reviewed the significance of two different forms of ACE2 (mACE2 and sACE2) and gender on COVID-19 susceptibility and severity. This review summarizes COVID-19 pathophysiology and the best strategies for clinical management of diabetes patients with COVID-19.
Collapse
Affiliation(s)
| | | | | | | | | | - Weihua Wu
- Department of Endocrinology, The 3rd Affiliated Hospital of Shenzhen University, Shenzhen, China
| |
Collapse
|
5
|
Masomian M, Lalani S, Poh CL. Molecular Docking of SP40 Peptide towards Cellular Receptors for Enterovirus 71 (EV-A71). Molecules 2021; 26:molecules26216576. [PMID: 34770987 PMCID: PMC8587434 DOI: 10.3390/molecules26216576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 10/13/2021] [Accepted: 10/26/2021] [Indexed: 11/16/2022] Open
Abstract
Enterovirus 71 (EV-A71) is one of the predominant etiological agents of hand, foot and mouth disease (HMFD), which can cause severe central nervous system infections in young children. There is no clinically approved vaccine or antiviral agent against HFMD. The SP40 peptide, derived from the VP1 capsid of EV-A71, was reported to be a promising antiviral peptide that targeted the host receptor(s) involved in viral attachment or entry. So far, the mechanism of action of SP40 peptide is unknown. In this study, interactions between ten reported cell receptors of EV-A71 and the antiviral SP40 peptide were evaluated through molecular docking simulations, followed by in vitro receptor blocking with specific antibodies. The preferable binding region of each receptor to SP40 was predicted by global docking using HPEPDOCK and the cell receptor-SP40 peptide complexes were refined using FlexPepDock. Local molecular docking using GOLD (Genetic Optimization for Ligand Docking) showed that the SP40 peptide had the highest binding score to nucleolin followed by annexin A2, SCARB2 and human tryptophanyl-tRNA synthetase. The average GoldScore for 5 top-scoring models of human cyclophilin, fibronectin, human galectin, DC-SIGN and vimentin were almost similar. Analysis of the nucleolin-SP40 peptide complex showed that SP40 peptide binds to the RNA binding domains (RBDs) of nucleolin. Furthermore, receptor blocking by specific monoclonal antibody was performed for seven cell receptors of EV-A71 and the results showed that the blocking of nucleolin by anti-nucleolin alone conferred a 93% reduction in viral infectivity. Maximum viral inhibition (99.5%) occurred when SCARB2 was concurrently blocked with anti-SCARB2 and the SP40 peptide. This is the first report to reveal the mechanism of action of SP40 peptide in silico through molecular docking analysis. This study provides information on the possible binding site of SP40 peptide to EV-A71 cellular receptors. Such information could be useful to further validate the interaction of the SP40 peptide with nucleolin by site-directed mutagenesis of the nucleolin binding site.
Collapse
Affiliation(s)
- Malihe Masomian
- Correspondence: (M.M.); (C.L.P.); Tel.: +603-74918622 (ext. 7603) (M.M.); +603-74918622 (ext. 7338) (C.L.P.)
| | | | - Chit Laa Poh
- Correspondence: (M.M.); (C.L.P.); Tel.: +603-74918622 (ext. 7603) (M.M.); +603-74918622 (ext. 7338) (C.L.P.)
| |
Collapse
|
6
|
Murakami T, Ono A. Roles of Virion-Incorporated CD162 (PSGL-1), CD43, and CD44 in HIV-1 Infection of T Cells. Viruses 2021; 13:v13101935. [PMID: 34696365 PMCID: PMC8541244 DOI: 10.3390/v13101935] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/18/2021] [Accepted: 09/22/2021] [Indexed: 11/16/2022] Open
Abstract
Nascent HIV-1 particles incorporate the viral envelope glycoprotein and multiple host transmembrane proteins during assembly at the plasma membrane. At least some of these host transmembrane proteins on the surface of virions are reported as pro-viral factors that enhance virus attachment to target cells or facilitate trans-infection of CD4+ T cells via interactions with non-T cells. In addition to the pro-viral factors, anti-viral transmembrane proteins are incorporated into progeny virions. These virion-incorporated transmembrane proteins inhibit HIV-1 entry at the point of attachment and fusion. In infected polarized CD4+ T cells, HIV-1 Gag localizes to a rear-end protrusion known as the uropod. Regardless of cell polarization, Gag colocalizes with and promotes the virion incorporation of a subset of uropod-directed host transmembrane proteins, including CD162, CD43, and CD44. Until recently, the functions of these virion-incorporated proteins had not been clear. Here, we review the recent findings about the roles played by virion-incorporated CD162, CD43, and CD44 in HIV-1 spread to CD4+ T cells.
Collapse
|
7
|
Suppression of DC-SIGN and gH Reveals Complex, Subset-Specific Mechanisms for KSHV Entry in Primary B Lymphocytes. Viruses 2021; 13:v13081512. [PMID: 34452377 PMCID: PMC8402705 DOI: 10.3390/v13081512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 12/28/2022] Open
Abstract
Kaposi sarcoma-associated herpesvirus (KSHV) is the causative agent of multiple cancers in immunocompromised patients including two lymphoproliferative disorders associated with KSHV infection of B lymphocytes. Despite many years of research into the pathogenesis of KSHV associated diseases, basic questions related to KSHV molecular virology remain unresolved. One such unresolved question is the cellular receptors and viral glycoproteins needed for KSHV entry into primary B lymphocytes. In this study, we assess the contributions of KSHV glycoprotein H (gH) and the cellular receptor DC-SIGN to KSHV infection in tonsil-derived B lymphocytes. Our results show that (1) neither KSHV-gH nor DC-SIGN are essential for entry into any B cell subset, (2) DC-SIGN does play a role in KSHV entry into tonsil-derived B cells, but in all B cell subtypes alternative entry mechanisms exist, (3) KSHV-gH can participate in KSHV entry into centrocytes via a DC-SIGN independent entry mechanism, and (4) in the absence of KSHV-gH, DC-SIGN is required for KSHV entry into centrocytes. Our results provide a first glimpse into the complexity of KSHV entry in the lymphocyte compartment and highlight that multiple subset-dependent entry mechanisms are employed by KSHV which depend upon multiple cellular receptors and multiple KSHV glycoproteins.
Collapse
|
8
|
Amraei R, Yin W, Napoleon MA, Suder EL, Berrigan J, Zhao Q, Olejnik J, Chandler KB, Xia C, Feldman J, Hauser BM, Caradonna TM, Schmidt AG, Gummuluru S, Mühlberger E, Chitalia V, Costello CE, Rahimi N. CD209L/L-SIGN and CD209/DC-SIGN Act as Receptors for SARS-CoV-2. ACS CENTRAL SCIENCE 2021; 7:1156-1165. [PMID: 34341769 PMCID: PMC8265543 DOI: 10.1021/acscentsci.0c01537] [Citation(s) in RCA: 144] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Indexed: 05/17/2023]
Abstract
As the COVID-19 pandemic continues to spread, investigating the processes underlying the interactions between SARS-CoV-2 and its hosts is of high importance. Here, we report the identification of CD209L/L-SIGN and the related protein CD209/DC-SIGN as receptors capable of mediating SARS-CoV-2 entry into human cells. Immunofluorescence staining of human tissues revealed prominent expression of CD209L in the lung and kidney epithelia and endothelia. Multiple biochemical assays using a purified recombinant SARS-CoV-2 spike receptor-binding domain (S-RBD) or S1 encompassing both N termal domain and RBD and ectopically expressed CD209L and CD209 revealed that CD209L and CD209 interact with S-RBD. CD209L contains two N-glycosylation sequons, at sites N92 and N361, but we determined that only site N92 is occupied. Removal of the N-glycosylation at this site enhances the binding of S-RBD with CD209L. CD209L also interacts with ACE2, suggesting a role for heterodimerization of CD209L and ACE2 in SARS-CoV-2 entry and infection in cell types where both are present. Furthermore, we demonstrate that human endothelial cells are permissive to SARS-CoV-2 infection, and interference with CD209L activity by a knockdown strategy or with soluble CD209L inhibits virus entry. Our observations demonstrate that CD209L and CD209 serve as alternative receptors for SARS-CoV-2 in disease-relevant cell types, including the vascular system. This property is particularly important in tissues where ACE2 has low expression or is absent and may have implications for antiviral drug development.
Collapse
Affiliation(s)
- Razie Amraei
- Department
of Pathology, School of Medicine, Boston
University Medical Campus, Boston, Massachusetts 02118, United States
| | - Wenqing Yin
- Renal
Section, Department of Medicine, Boston
University Medical Center, Boston, Massachusetts 02118, United States
| | - Marc A. Napoleon
- Renal
Section, Department of Medicine, Boston
University Medical Center, Boston, Massachusetts 02118, United States
| | - Ellen L. Suder
- Department
of Microbiology, Boston University School
of Medicine, Boston, Massachusetts 02118, United States
- National
Emerging Infectious Diseases Laboratories (NEIDL), Boston University, Boston, Massachusetts 02118, United States
| | - Jacob Berrigan
- Department
of Microbiology, Boston University School
of Medicine, Boston, Massachusetts 02118, United States
| | - Qing Zhao
- Department
of Pathology, School of Medicine, Boston
University Medical Campus, Boston, Massachusetts 02118, United States
| | - Judith Olejnik
- Department
of Microbiology, Boston University School
of Medicine, Boston, Massachusetts 02118, United States
- National
Emerging Infectious Diseases Laboratories (NEIDL), Boston University, Boston, Massachusetts 02118, United States
| | - Kevin Brown Chandler
- Center
for Biomedical Mass Spectrometry, Boston
University School of Medicine, Boston, Massachusetts 02118, United States
| | - Chaoshuang Xia
- Center
for Biomedical Mass Spectrometry, Boston
University School of Medicine, Boston, Massachusetts 02118, United States
| | - Jared Feldman
- Ragon Institute
of MGH, MIT, and Harvard, Cambridge, Massachusetts 02139, United States
| | - Blake M. Hauser
- Ragon Institute
of MGH, MIT, and Harvard, Cambridge, Massachusetts 02139, United States
| | - Timothy M. Caradonna
- Ragon Institute
of MGH, MIT, and Harvard, Cambridge, Massachusetts 02139, United States
| | - Aaron G. Schmidt
- Ragon Institute
of MGH, MIT, and Harvard, Cambridge, Massachusetts 02139, United States
- Department
of Microbiology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Suryaram Gummuluru
- Department
of Microbiology, Boston University School
of Medicine, Boston, Massachusetts 02118, United States
| | - Elke Mühlberger
- Department
of Microbiology, Boston University School
of Medicine, Boston, Massachusetts 02118, United States
- National
Emerging Infectious Diseases Laboratories (NEIDL), Boston University, Boston, Massachusetts 02118, United States
| | - Vipul Chitalia
- Renal
Section, Department of Medicine, Boston
University Medical Center, Boston, Massachusetts 02118, United States
| | - Catherine E. Costello
- Center
for Biomedical Mass Spectrometry, Boston
University School of Medicine, Boston, Massachusetts 02118, United States
| | - Nader Rahimi
- Department
of Pathology, School of Medicine, Boston
University Medical Campus, Boston, Massachusetts 02118, United States
| |
Collapse
|
9
|
Circumcision as an Intervening Strategy against HIV Acquisition in the Male Genital Tract. Pathogens 2021; 10:pathogens10070806. [PMID: 34201976 PMCID: PMC8308621 DOI: 10.3390/pathogens10070806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/04/2021] [Accepted: 06/24/2021] [Indexed: 12/15/2022] Open
Abstract
Unsafe sex with HIV-infected individuals remains a major route for HIV transmission, and protective strategies, such as the distribution of free condoms and pre-or post-prophylaxis medication, have failed to control the spread of HIV, particularly in resource-limited settings and high HIV prevalence areas. An additional key strategy for HIV prevention is voluntary male circumcision (MC). International health organizations (e.g., the World Health Organization, UNAIDS) have recommended this strategy on a larger scale, however, there is a general lack of public understanding about how MC effectively protects against HIV infection. This review aims to discuss the acquisition of HIV through the male genital tract and explain how and why circumcised men are more protected from HIV infection during sexual activity than uncircumcised men who are at higher risk of HIV acquisition.
Collapse
|
10
|
Amraei R, Yin W, Napoleon MA, Suder EL, Berrigan J, Zhao Q, Olejnik J, Chandler KB, Xia C, Feldman J, Hauser BM, Caradonna TM, Schmidt AG, Gummuluru S, Muhlberger E, Chitalia V, Costello CE, Rahimi N. CD209L/L-SIGN and CD209/DC-SIGN act as receptors for SARS-CoV-2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021:2020.06.22.165803. [PMID: 32607506 PMCID: PMC7325172 DOI: 10.1101/2020.06.22.165803] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
As the COVID-19 pandemic continues to spread, investigating the processes underlying the interactions between SARS-CoV-2 and its hosts is of high importance. Here, we report the identification of CD209L/L-SIGN and the related protein CD209/DC-SIGN as receptors capable of mediating SARS-CoV-2 entry into human cells. Immunofluorescence staining of human tissues revealed prominent expression of CD209L in the lung and kidney epithelium and endothelium. Multiple biochemical assays using a purified recombinant SARS-CoV-2 spike receptor binding domain (S-RBD) or S1 encompassing both NTB and RBD and ectopically expressed CD209L and CD209 revealed that CD209L and CD209 interact with S-RBD. CD209L contains two N-glycosylation sequons, at sites N92 and N361, but we determined that only site N92 is occupied. Removal of the N-glycosylation at this site enhances the binding of S-RBD with CD209L. CD209L also interacts with ACE2, suggesting a role for heterodimerization of CD209L and ACE2 in SARS-CoV-2 entry and infection in cell types where both are present. Furthermore, we demonstrate that human endothelial cells are permissive to SARS-CoV-2 infection and interference with CD209L activity by knockdown strategy or with soluble CD209L inhibits virus entry. Our observations demonstrate that CD209L and CD209 serve as alternative receptors for SARS-CoV-2 in disease-relevant cell types, including the vascular system. This property is particularly important in tissues where ACE2 has low expression or is absent, and may have implications for antiviral drug development.
Collapse
Affiliation(s)
- Razie Amraei
- Department of Pathology, School of Medicine, Boston University Medical Campus, Boston, MA 02118
| | - Wenqing Yin
- Renal Section, Department of Medicine, Boston University Medical Center, Boston, MA
| | - Marc A. Napoleon
- Renal Section, Department of Medicine, Boston University Medical Center, Boston, MA
| | - Ellen L. Suder
- Department of Microbiology, Boston University School of Medicine, Boston, MA
- National Emerging Infectious Diseases Laboratories (NEIDL), Boston University, Boston, MA
| | - Jacob Berrigan
- Department of Microbiology, Boston University School of Medicine, Boston, MA
| | - Qing Zhao
- Department of Pathology, School of Medicine, Boston University Medical Campus, Boston, MA 02118
| | - Judith Olejnik
- Department of Microbiology, Boston University School of Medicine, Boston, MA
- National Emerging Infectious Diseases Laboratories (NEIDL), Boston University, Boston, MA
| | - Kevin Brown Chandler
- Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA 02118
| | - Chaoshuang Xia
- Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA 02118
| | - Jared Feldman
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139
| | - Blake M. Hauser
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139
| | | | - Aaron G. Schmidt
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139
- Department of Microbiology, Harvard Medical School, Boston, MA 02115
| | - Suryaram Gummuluru
- Department of Microbiology, Boston University School of Medicine, Boston, MA
| | - Elke Muhlberger
- Department of Microbiology, Boston University School of Medicine, Boston, MA
- National Emerging Infectious Diseases Laboratories (NEIDL), Boston University, Boston, MA
| | - Vipul Chitalia
- Renal Section, Department of Medicine, Boston University Medical Center, Boston, MA
| | - Catherine E. Costello
- Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA 02118
| | - Nader Rahimi
- Department of Pathology, School of Medicine, Boston University Medical Campus, Boston, MA 02118
| |
Collapse
|
11
|
B Lymphocytes, but Not Dendritic Cells, Efficiently HIV-1 Trans Infect Naive CD4 + T Cells: Implications for the Viral Reservoir. mBio 2021; 12:mBio.02998-20. [PMID: 33688006 PMCID: PMC8092276 DOI: 10.1128/mbio.02998-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Insight into the establishment and maintenance of HIV-1 infection in resting CD4+ T cell subsets is critical for the development of therapeutics targeting the HIV-1 reservoir. Although the frequency of HIV-1 infection, as quantified by the frequency of HIV-1 DNA, is lower in CD4+ naive T cells (TN) than in the memory T cell subsets, recent studies have shown that TN harbor a large pool of replication-competent virus. Interestingly, however, TN are highly resistant to direct (cis) HIV-1 infection in vitro, in particular to R5-tropic HIV-1, as TN do not express CCR5. In this study, we investigated whether TN could be efficiently HIV-1 trans infected by professional antigen-presenting B lymphocytes and myeloid dendritic cells (DC) in the absence of global T cell activation. We found that B cells, but not DC, have a unique ability to efficiently trans infect TNin vitro In contrast, both B cells and DC mediated HIV-1 trans infection of memory and activated CD4+ T cells. Moreover, we found that TN isolated from HIV-1-infected nonprogressors (NP) harbor significantly disproportionately lower levels of HIV-1 DNA than TN isolated from progressors. This is consistent with our previous finding that antigen-presenting cells (APC) derived from NP do not efficiently trans infect CD4+ T cells due to alterations in APC cholesterol metabolism and cell membrane lipid raft organization. These findings support that B cell-mediated trans infection of TN with HIV-1 has a more profound role than previously considered in establishing the viral reservoir and control of HIV-1 disease progression.IMPORTANCE The latent human immunodeficiency virus type 1 (HIV-1) reservoir in persons on antiretroviral therapy (ART) represents a major barrier to a cure. Although most studies have focused on the HIV-1 reservoir in the memory T cell subset, replication-competent HIV-1 has been isolated from TN, and CCR5-tropic HIV-1 has been recovered from CCR5neg TN from ART-suppressed HIV-1-infected individuals. In this study, we showed that CCR5neg TN are efficiently trans infected with R5-tropic HIV-1 by B lymphocytes, but not by myeloid dendritic cells. Furthermore, we found that TN isolated from NP harbor no or significantly fewer copies of HIV-1 DNA than those from ART-suppressed progressors. These findings support that B cell-mediated trans infection of TN with HIV-1 has a more profound role than previously considered in establishing the viral reservoir and control of HIV-1 disease progression. Understanding the establishment and maintenance of the HIV-1 latent reservoir is fundamental for the design of effective treatments for viral eradication.
Collapse
|
12
|
Innate Immune Pattern Recognition Receptors of Mycobacterium tuberculosis: Nature and Consequences for Pathogenesis of Tuberculosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1313:179-215. [PMID: 34661896 DOI: 10.1007/978-3-030-67452-6_9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Innate immunity against Mycobacterium tuberculosis is a critical early response to prevent the establishment of the infection. Despite recent advances in understanding the host-pathogen dialogue in the early stages of tuberculosis (TB), much has yet to be learnt. The nature and consequences of this dialogue ultimately determine the path of infection: namely, either early clearance of M. tuberculosis, or establishment of M. tuberculosis infection leading to active TB disease and/or latent TB infection. On the frontline in innate immunity are pattern recognition receptors (PRRs), with soluble factors (e.g. collectins and complement) and cell surface factors (e.g. Toll-like receptors and other C-type lectin receptors (Dectin 1/2, Nod-like receptors, DC-SIGN, Mincle, mannose receptor, and MCL) that play a central role in recognising M. tuberculosis and facilitating its clearance. However, in a 'double-edged sword' scenario, these factors can also be involved in enhancement of pathogenesis as well. Furthermore, innate immunity is also a critical bridge in establishing the subsequent adaptive immune response, which is also responsible for granuloma formation that cordons off M. tuberculosis infection, establishing latency and acting as a reservoir for bacterial persistence and dissemination of future disease. This chapter discusses the current understanding of pattern recognition of M. tuberculosis by innate immunity and the role this plays in the pathogenesis and protection against TB.
Collapse
|
13
|
Abstract
The innate immune system is comprised of both cellular and humoral players that recognise and eradicate invading pathogens. Therefore, the interplay between retroviruses and innate immunity has emerged as an important component of viral pathogenesis. HIV-1 infection in humans that results in hematologic abnormalities and immune suppression is well represented by changes in the CD4/CD8 T cell ratio and consequent cell death causing CD4 lymphopenia. The innate immune responses by mucosal barriers such as complement, DCs, macrophages, and NK cells as well as cytokine/chemokine profiles attain great importance in acute HIV-1 infection, and thus, prevent mucosal capture and transmission of HIV-1. Conversely, HIV-1 has evolved to overcome innate immune responses through RNA-mediated rapid mutations, pathogen-associated molecular patterns (PAMPs) modification, down-regulation of NK cell activity and complement receptors, resulting in increased secretion of inflammatory factors. Consequently, epithelial tissues lining up female reproductive tract express innate immune sensors including anti-microbial peptides responsible for forming primary barriers and have displayed an effective potent anti-HIV activity during phase I/II clinical trials.
Collapse
|
14
|
Rahimi N. C-type Lectin CD209L/L-SIGN and CD209/DC-SIGN: Cell Adhesion Molecules Turned to Pathogen Recognition Receptors. BIOLOGY 2020; 10:1. [PMID: 33375175 PMCID: PMC7822156 DOI: 10.3390/biology10010001] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 12/14/2020] [Accepted: 12/16/2020] [Indexed: 12/19/2022]
Abstract
C-type lectin CD209/DC-SIGN and CD209L/L-SIGN proteins are distinct cell adhesion and pathogen recognition receptors that mediate cellular interactions and recognize a wide range of pathogens, including viruses such as SARS, SARS-CoV-2, bacteria, fungi and parasites. Pathogens exploit CD209 family proteins to promote infection and evade the immune recognition system. CD209L and CD209 are widely expressed in SARS-CoV-2 target organs and can contribute to infection and pathogenesis. CD209 family receptors are highly susceptible to alternative splicing and genomic polymorphism, which may influence virus tropism and transmission in vivo. The carbohydrate recognition domain (CRD) and the neck/repeat region represent the key features of CD209 family proteins that are also central to facilitating cellular ligand interactions and pathogen recognition. While the neck/repeat region is involved in oligomeric dimerization, the CRD recognizes the mannose-containing structures present on specific glycoproteins such as those found on the SARS-CoV-2 spike protein. Considering the role of CD209L and related proteins in diverse pathogen recognition, this review article discusses the recent advances in the cellular and biochemical characterization of CD209 and CD209L and their roles in viral uptake, which has important implications in understanding the host-pathogen interaction, the viral pathobiology and driving vaccine development of SARS-CoV-2.
Collapse
Affiliation(s)
- Nader Rahimi
- Department of Pathology, School of Medicine, Boston University Medical Campus, Boston, MA 02118, USA
| |
Collapse
|
15
|
Aalam F, Totonchy J. Molecular Virology of KSHV in the Lymphocyte Compartment-Insights From Patient Samples and De Novo Infection Models. Front Cell Infect Microbiol 2020; 10:607663. [PMID: 33344267 PMCID: PMC7746649 DOI: 10.3389/fcimb.2020.607663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/09/2020] [Indexed: 12/26/2022] Open
Abstract
The incidence of Kaposi’s sarcoma-associated herpesvirus (KSHV)-associated Kaposi Sarcoma has declined precipitously in the present era of effective HIV treatment. However, KSHV-associated lymphoproliferative disorders although rare, have not seen a similar decline. Lymphoma is now a leading cause of death in people living with HIV (PLWH), indicating that the immune reconstitution provided by antiretroviral therapy is not sufficient to fully correct the lymphomagenic immune dysregulation perpetrated by HIV infection. As such, novel insights into the mechanisms of KSHV-mediated pathogenesis in the immune compartment are urgently needed in order to develop novel therapeutics aimed at prevention and treatment of KSHV-associated lymphoproliferations. In this review, we will discuss our current understanding of KSHV molecular virology in the lymphocyte compartment, concentrating on studies which explore mechanisms unique to infection in B lymphocytes.
Collapse
Affiliation(s)
- Farizeh Aalam
- Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, United States
| | - Jennifer Totonchy
- Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, United States
| |
Collapse
|
16
|
Ojeda N, Salazar C, Cárdenas C, Marshall SH. Expression of DC-SIGN-like C-Type Lectin Receptors in Salmo salar. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 113:103806. [PMID: 32739503 PMCID: PMC7392198 DOI: 10.1016/j.dci.2020.103806] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/20/2020] [Accepted: 07/20/2020] [Indexed: 05/05/2023]
Abstract
C-Type Lectin Receptors (CTLR) are involved in the activation of innate and adaptative immune responses. Among these receptors, the Dendritic Cell-Specific ICAM-3-Grabbing nonintegrin (DC-SIGN/CD209) has become a hot topic due to its ability to bind and facilitate the infections processes of several pathogens. Although well characterized in mammals, little documentation exists about the receptor in salmonid fishes. Here, we report the sequence and expression analysis of eight DC-SIGN-like genes in Salmo salar. Each receptor displays structural similarities to DC-SIGN molecules described in mammals, including internalization motifs, a neck region with heptad repeats, and a Ca+2-dependent carbohydrate recognition domain. The receptors are expressed in multiple tissues of fish, and fish cell lines, with differential expression upon infection with viral and bacterial pathogens. The identification of DC-SIGN-like receptors in Salmo salar provides new information regarding the structure of the immune system of salmon, potential markers for cell subsets, as well as insights into DC-SIGN conservation across species.
Collapse
Affiliation(s)
- Nicolás Ojeda
- Instituto de Biologia, Pontificia Universidad Catolica de Valparaiso, Valparaiso, Chile
| | - Carolina Salazar
- Instituto de Biologia, Pontificia Universidad Catolica de Valparaiso, Valparaiso, Chile
| | - Constanza Cárdenas
- Instituto de Biologia, Pontificia Universidad Catolica de Valparaiso, Valparaiso, Chile
| | - Sergio H Marshall
- Instituto de Biologia, Pontificia Universidad Catolica de Valparaiso, Valparaiso, Chile.
| |
Collapse
|
17
|
Ex vivo rectal explant model reveals potential opposing roles of Natural Killer cells and Marginal Zone-like B cells in HIV-1 infection. Sci Rep 2020; 10:20154. [PMID: 33214610 PMCID: PMC7677325 DOI: 10.1038/s41598-020-76976-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 10/28/2020] [Indexed: 12/15/2022] Open
Abstract
Our understanding of innate immune responses in human rectal mucosal tissues (RM) and their contributions to promoting or restricting HIV transmission is limited. We defined the RM composition of innate and innate-like cell subsets, including plasmacytoid dendritic cells; CD1c + myeloid DCs; neutrophils; macrophages; natural killer cells (NK); Marginal Zone-like B cells (MZB); γδ T cells; and mucosal-associated invariant T cells in RM from 69 HIV-negative men by flow cytometry. Associations between these cell subsets and HIV-1 replication in ex vivo RM explant challenge experiments revealed an inverse correlation between RM-NK and p24 production, in contrast to a positive association between RM-MZB and HIV replication. Comparison of RM and blood-derived MZB and NK illustrated qualitative and quantitative differences between tissue compartments. Additionally, 22 soluble molecules were measured in a subset of explant cultures (n = 26). Higher production of IL-17A, IFN-γ, IL-10, IP-10, GM-CSF, sFasL, Granzyme A, Granzyme B, Granulysin, and Perforin following infection positively correlated with HIV replication. These data show novel associations between MZB and NK cells and p24 production in RM and underscore the importance of inflammatory cytokines in mucosal HIV infection, demonstrating the likely critical role these innate immune responses play in early mucosal HIV replication in humans.
Collapse
|
18
|
Frequent expression of activation-induced cytidine deaminase in diffuse large B-cell lymphoma tissues from persons living with HIV. AIDS 2020; 34:2025-2035. [PMID: 32773475 PMCID: PMC9306295 DOI: 10.1097/qad.0000000000002653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE The increased risk for persons living with HIV to develop diffuse large B-cell lymphoma (DLBCL) even in the post-antiretroviral therapy eras suggests a role beyond immunosuppression in lymphoma development. However, the mechanisms leading to lymphoma in the HIV setting are not fully understood. HIV is known to induce activation-induced cytidine deaminase (AID) levels in nonneoplastic B cells in vitro and chronic AID expression may play an important role in lymphomagenesis. Although AID expression is observed in B-cell lymphoma, studies in HIV-associated DLBCL are limited. DESIGN In this study, we conducted a retrospective review of DLBCL tissues from patients with and without HIV infection to compare expression of AID and B-cell receptors potentially involved in HIV and B-cell interaction. METHODS We evaluated DLBCL formalin-fixed paraffin-embedded tissues from 72 HIV-seropositive and 58 HIV-seronegative patients for AID, DC-SIGN, and CD40 protein expression. BCL2 and MYC, two well established prognostically significant oncoproteins in DLBCL, were also assessed at the protein and mRNA levels. Subset analysis was performed according to DLBCL subtype and EBV status. RESULTS Of note, AID expression was more frequent in HIV-associated DLBCL compared with non-HIV-associated DLBCL regardless of cell-of-origin subtype, and also displayed significantly less BCL2 expression. Despite no direct correlation with AID expression, the HIV-DLBCL tissues also exhibited high levels of the DC-SIGN receptor. CONCLUSION Collectively, these findings support a potential role for AID in the pathogenesis of HIV-associated lymphomas and suggest the need of further investigations into the involvement of the DC-SIGN receptor-signaling pathway.
Collapse
|
19
|
Wang TT, Ravetch JV. Functional diversification of IgGs through Fc glycosylation. J Clin Invest 2020; 129:3492-3498. [PMID: 31478910 DOI: 10.1172/jci130029] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
IgG antibodies are secreted from B cells and bind to a variety of pathogens to control infections as well as contribute to inflammatory diseases. Many of the functions of IgGs are mediated through Fcγ receptors (FcγRs), which transduce interactions with immune complexes, leading to a variety of cellular outcomes depending on the FcγRs and cell types engaged. Which FcγRs and cell types will be engaged during an immune response depends on the structure of Fc domains within immune complexes that are formed when IgGs bind to cognate antigen(s). Recent studies have revealed an unexpected degree of structural variability in IgG Fc domains among people, driven primarily by differences in IgG subclasses and N-linked glycosylation of the CH2 domain. This translates, in turn, to functional immune diversification through type I and type II FcγR-mediated cellular functions. For example, Fc domain sialylation triggers conformational changes of IgG1 that enable interactions with type II FcγRs; these receptors mediate cellular functions including antiinflammatory activity or definition of thresholds for B cell selection based on B cell receptor affinity. Similarly, presence or absence of a core fucose alters type I FcγR binding of IgG1 by modulating the Fc's affinity for FcγRIIIa, thereby altering its proinflammatory activity. How heterogeneity in IgG Fc domains contributes to human immune diversity is now being elucidated, including impacts on vaccine responses and susceptibility to disease and its sequelae during infections. Here, we discuss how Fc structures arising from sialylation and fucosylation impact immunity, focusing on responses to vaccination and infection. We also review work defining individual differences in Fc glycosylation, regulation of Fc glycosylation, and clinical implications of these pathways.
Collapse
Affiliation(s)
- Taia T Wang
- Department of Medicine, Division of Infectious Diseases, and Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California, USA.,Chan Zuckerberg Biohub, San Francisco, California, USA
| | - Jeffrey V Ravetch
- Laboratory of Molecular Genetics and Immunology, The Rockefeller University, New York, New York, USA
| |
Collapse
|
20
|
Darcis G, Berkhout B, Pasternak AO. The Quest for Cellular Markers of HIV Reservoirs: Any Color You Like. Front Immunol 2019; 10:2251. [PMID: 31616425 PMCID: PMC6763966 DOI: 10.3389/fimmu.2019.02251] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 09/05/2019] [Indexed: 12/12/2022] Open
Abstract
Combination antiretroviral therapy (ART) suppresses human immunodeficiency virus (HIV) replication and improves immune function, but is unable to eradicate the virus. Therefore, development of an HIV cure has become one of the main priorities of the HIV research field. The main obstacle for an HIV cure is the formation of latent viral reservoirs, where the virus is able to “hide” despite decades of therapy, just to reignite active replication once therapy is stopped. Revealing HIV hiding places is thus central to HIV cure research, but the absence of markers of these reservoir cells greatly complicates the search for a cure. Identification of one or several marker(s) of latently infected cells would represent a significant step forward toward a better description of the cell types involved and improved understanding of HIV latency. Moreover, it could provide a “handle” for selective therapeutic targeting of the reservoirs. A number of cellular markers of HIV reservoir have recently been proposed, including immune checkpoint molecules, CD2, and CD30. CD32a is perhaps the most promising of HIV reservoir markers as it is reported to be associated with a very prominent enrichment in HIV DNA, although this finding has been challenged. In this review, we provide an update on the current knowledge about HIV reservoir markers. We specifically highlight studies that characterized markers of persistently infected cells in the lymphoid tissues.
Collapse
Affiliation(s)
- Gilles Darcis
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Infectious Diseases Department, Liège University Hospital, Liège, Belgium
| | - Ben Berkhout
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Alexander O Pasternak
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| |
Collapse
|
21
|
Qin K, Boppana S, Du VY, Carlson JM, Yue L, Dilernia DA, Hunter E, Mailliard RB, Mallal SA, Bansal A, Goepfert PA. CD8 T cells targeting adapted epitopes in chronic HIV infection promote dendritic cell maturation and CD4 T cell trans-infection. PLoS Pathog 2019; 15:e1007970. [PMID: 31398241 PMCID: PMC6703693 DOI: 10.1371/journal.ppat.1007970] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 08/21/2019] [Accepted: 07/08/2019] [Indexed: 11/18/2022] Open
Abstract
HIV-1 frequently escapes from CD8 T cell responses via HLA-I restricted adaptation, leading to the accumulation of adapted epitopes (AE). We previously demonstrated that AE compromise CD8 T cell responses during acute infection and are associated with poor clinical outcomes. Here, we examined the impact of AE on CD8 T cell responses and their biological relevance in chronic HIV infection (CHI). In contrast to acute infection, the majority of AE are immunogenic in CHI. Longitudinal analyses from acute to CHI showed an increased frequency and magnitude of AE-specific IFNγ responses compared to NAE-specific ones. These AE-specific CD8 T cells also were more cytotoxic to CD4 T cells. In addition, AE-specific CD8 T cells expressed lower levels of PD1 and CD57, as well as higher levels of CD28, suggesting a more activated and less exhausted phenotype. During CHI, viral sequencing identified AE-encoding strains as the dominant quasispecies. Despite increased CD4 T cell cytotoxicity, CD8 T cells responding to AE promoted dendritic cell (DC) maturation and CD4 T cell trans-infection perhaps explaining why AE are predominant in CHI. Taken together, our data suggests that the emergence of AE-specific CD8 T cell responses in CHI confers a selective advantage to the virus by promoting DC-mediated CD4 T cell trans-infection. HIV-1 infection remains a critical public health threat across the world. Over the past two decades, CD8 T cells have been clearly shown to exert immune pressure on HIV and drive viral adaptation. Previously, our group reported that such HLA-I associated adaptations can predict clinical outcomes and are beneficial to HIV-1 as CD8 T cells are unable to recognize epitopes with adaptation in acute HIV infection. However, it is still unclear how HIV-1 adaptation impacts CD8 T cells during chronic HIV infection. In this study, we observed an enhancement of CD8 T cell responses targeting adapted epitopes in chronic infection. Although these responses were cytotoxic, they also exhibited a “helper” effect by promoting viral infection of CD4 T cells via interaction with dendritic cells. This phenomenon may contribute to the persistence of adapted viruses. In summary, these findings present a novel mechanism of CD8 T cell driven HIV-1 adaptation.
Collapse
Affiliation(s)
- Kai Qin
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Sushma Boppana
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Victor Y. Du
- The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | | | - Ling Yue
- Emory Vaccine Center at Yerkes National Primate Research Center and Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Dario A. Dilernia
- Emory Vaccine Center at Yerkes National Primate Research Center and Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Eric Hunter
- Emory Vaccine Center at Yerkes National Primate Research Center and Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Robbie B. Mailliard
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Simon A. Mallal
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Anju Bansal
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- * E-mail: (AB); (PAG)
| | - Paul A. Goepfert
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- * E-mail: (AB); (PAG)
| |
Collapse
|
22
|
Rappocciolo G, Sluis-Cremer N, Rinaldo CR. Efficient HIV-1 Trans Infection of CD4 + T Cells Occurs in the Presence of Antiretroviral Therapy. Open Forum Infect Dis 2019; 6:ofz253. [PMID: 31304185 PMCID: PMC6613953 DOI: 10.1093/ofid/ofz253] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 05/23/2019] [Indexed: 11/21/2022] Open
Abstract
Background Antiretroviral therapy (ART) has dramatically improved the quality of life of people with HIV-1 infection (PWH). However, it is not curative, and interruption of ART results in rapid viral rebound. Cell-to-cell transfer of HIV-1, or trans infection, is a highly efficient mechanism of virus infection of CD4+ T cells by professional antigen-presenting cells (APCs), that is, dendritic cells (DCs), macrophages, and B lymphocytes. Methods APC from HIV seronegative donors treated with ART in vitro (CCR5 agonist, NRTI, PI and NNRTI, alone or in combination), were loaded with HIV R5-tropic HIVBal and mixed with autologous or heterologous CD4+ T lymphocytes to assess trans infection. Ex vivo APC from chronic HIV-infected MACS participants before and after initiation of ART, were also loaded with HIV R5-tropic HIVBal and tested for trans infection against autologous or heterologous CD4+ T lymphocytes. Virus replication was measured by p24 ELISA. Results Here we show in vitro that antiretroviral drugs did not block the ability of DCs and B cells to trans-infect CD4+ T cells, although they were effective in blocking direct cis infection of CD4+ T cells. Moreover, ex vivo DCs and B cells from ART-suppressed PWH mediated efficient HIV-1 trans infection of CD4+ T cells, which were resistant to direct cis infection. Conclusions Our study supports a role for HIV-1 trans infection in maintenance of the HIV-1 reservoir during ART.
Collapse
Affiliation(s)
- Giovanna Rappocciolo
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Nicolas Sluis-Cremer
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Charles R Rinaldo
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| |
Collapse
|
23
|
Colomb F, Giron LB, Trbojevic-Akmacic I, Lauc G, Abdel-Mohsen M. Breaking the Glyco-Code of HIV Persistence and Immunopathogenesis. Curr HIV/AIDS Rep 2019; 16:151-168. [PMID: 30707400 PMCID: PMC6441623 DOI: 10.1007/s11904-019-00433-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW Glycoimmunology is an emerging field focused on understanding how immune responses are mediated by glycans (carbohydrates) and their interaction with glycan-binding proteins called lectins. How glycans influence immunological functions is increasingly well understood. In a parallel way, in the HIV field, it is increasingly understood how the host immune system controls HIV persistence and immunopathogenesis. However, what has mostly been overlooked, despite its potential for therapeutic applications, is the role that the host glycosylation machinery plays in modulating the persistence and immunopathogenesis of HIV. Here, we will survey four areas in which the links between glycan-lectin interactions and immunology and between immunology and HIV are well described. For each area, we will describe these links and then delineate the opportunities for the HIV field in investigating potential interactions between glycoimmunology and HIV persistence/immunopathogenesis. RECENT FINDINGS Recent studies show that the human glycome (the repertoire of human glycan structures) plays critical roles in driving or modulating several cellular processes and immunological functions that are central to maintaining HIV infection. Understanding the links between glycoimmunology and HIV infection may create a new paradigm for discovering novel glycan-based therapies that can lead to eradication, functional cure, or improved tolerance of lifelong infection.
Collapse
Affiliation(s)
- Florent Colomb
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, USA
| | - Leila B Giron
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, USA
| | | | - Gordan Lauc
- Genos Glycoscience Research Laboratory, Borongajska cesta 83h, Zagreb, Croatia
- Faculty of Pharmacy and Biochemistry, University of Zagreb, A. Kovacica 1, Zagreb, Croatia
| | | |
Collapse
|
24
|
Inefficient HIV-1 trans Infection of CD4 + T Cells by Macrophages from HIV-1 Nonprogressors Is Associated with Altered Membrane Cholesterol and DC-SIGN. J Virol 2018; 92:JVI.00092-18. [PMID: 29643243 PMCID: PMC6002718 DOI: 10.1128/jvi.00092-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 04/03/2018] [Indexed: 12/24/2022] Open
Abstract
Professional antigen-presenting cells (APC; myeloid dendritic cells [DC] and macrophages [MΦ]; B lymphocytes) mediate highly efficient HIV-1 infection of CD4+ T cells, termed trans infection, that could contribute to HIV-1 pathogenesis. We have previously shown that lower cholesterol content in DC and B lymphocytes is associated with a lack of HIV-1 trans infection in HIV-1-infected nonprogressors (NP). Here, we assessed whether HIV-1 trans infection mediated by another major APC, MΦ, is deficient in NP due to altered cholesterol metabolism. When comparing healthy HIV-1 seronegatives (SN), rapid progressors (PR), and NP, we found that monocyte-derived MΦ from NP did not mediate HIV-1 trans infection of autologous CD4+ T cells, in contrast to efficient trans infection mediated by SN and PR MΦ. MΦ trans infection efficiency was directly associated with the number of DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN)-expressing MΦ. Significantly fewer NP MΦ expressed DC-SIGN. Unesterified (free) cholesterol in MΦ cell membranes and lipid rafting was significantly lower in NP than PR, as was virus internalization in early endosomes. Furthermore, simvastatin (SIMV) decreased the subpopulation of DC-SIGN+ MΦ as well as cis and trans infection. Notably, SIMV decreased cell membrane cholesterol and led to lipid raft dissociation, effectively mimicking the incompetent APC trans infection environment characteristic of NP. Our data support that DC-SIGN and membrane cholesterol are central to MΦ trans infection, and a lack of these limits HIV-1 disease progression. Targeting the ability of MΦ to drive HIV-1 dissemination in trans could enhance HIV-1 therapeutic strategies. IMPORTANCE Despite the success of combination antiretroviral therapy, neither a vaccine nor a cure for HIV infection has been developed, demonstrating a need for novel prophylactic and therapeutic strategies. Here, we show that efficiency of MΦ-mediated HIV trans infection of CD4+ T cells is a unique characteristic associated with control of disease progression, and it is impaired in HIV-infected NP. In vitro treatment of MΦ from healthy donors with SIMV lowers their cholesterol content, which results in a strongly reduced trans infection ability, similar to the levels of MΦ from NP. Taken together, our data support the hypothesis that MΦ-mediated HIV-1 trans infection plays a role in HIV infection and disease progression and demonstrate that the use of SIMV to decrease this mechanism of virus transfer should be considered for future HIV therapeutic development.
Collapse
|
25
|
Human Herpesvirus 8 Infects and Replicates in Langerhans Cells and Interstitial Dermal Dendritic Cells and Impairs Their Function. J Virol 2017; 91:JVI.00909-17. [PMID: 28768873 PMCID: PMC5625489 DOI: 10.1128/jvi.00909-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 07/19/2017] [Indexed: 02/07/2023] Open
Abstract
The predominant types of dendritic cells (DC) in the skin and mucosa are Langerhans cells (LC) and interstitial dermal DC (iDDC). LC and iDDC process cutaneous antigens and migrate out of the skin and mucosa to the draining lymph nodes to present antigens to T and B cells. Because of the strategic location of LC and iDDC and the ability of these cells to capture and process pathogens, we hypothesized that they could be infected with human herpesvirus 8 (HHV-8) (Kaposi's sarcoma [KS]-associated herpesvirus) and have an important role in the development of KS. We have previously shown that HHV-8 enters monocyte-derived dendritic cells (MDDC) through DC-SIGN, resulting in nonproductive infection. Here we show that LC and iDDC generated from pluripotent cord blood CD34+ cell precursors support productive infection with HHV-8. Anti-DC-SIGN monoclonal antibody (MAb) inhibited HHV-8 infection of iDDC, as shown by low expression levels of viral proteins and DNA. In contrast, blocking of both langerin and the receptor protein tyrosine kinase ephrin A2 was required to inhibit HHV-8 infection of LC. Infection with HHV-8 did not alter the cell surface expression of langerin on LC but downregulated the expression of DC-SIGN on iDDC, as we previously reported for MDDC. HHV-8-infected LC and iDDC had a reduced ability to stimulate allogeneic CD4+ T cells in the mixed-lymphocyte reaction. These results indicate that HHV-8 can target both LC and iDDC for productive infection via different receptors and alter their function, supporting their potential role in HHV-8 pathogenesis and KS. IMPORTANCE Here we show that HHV-8, a DNA tumor virus that causes Kaposi's sarcoma, infects three types of dendritic cells: monocyte-derived dendritic cells, Langerhans cells, and interstitial dermal dendritic cells. We show that different receptors are used by this virus to infect these cells. DC-SIGN is a major receptor for infection of both monocyte-derived dendritic cells and interstitial dermal dendritic cells, yet the virus fully replicates only in the latter. HHV-8 uses langerin and the ephrin A2 receptor to infect Langerhans cells, which support full HHV-8 lytic replication. This infection of Langerhans cells and interstitial dermal dendritic cells results in an impaired ability to stimulate CD4+ helper T cell responses. Taken together, our data show that HHV-8 utilizes alternate receptors to differentially infect and replicate in these tissue-resident DC and support the hypothesis that these cells play an important role in HHV-8 infection and pathogenesis.
Collapse
|
26
|
Na-Ek P, Thewsoongnoen J, Thanunchai M, Wiboon-Ut S, Sa-Ard-Iam N, Mahanonda R, Thitithanyanont A. The activation of B cells enhances DC-SIGN expression and promotes susceptibility of B cells to HPAI H5N1 infection. Biochem Biophys Res Commun 2017; 490:1301-1306. [PMID: 28688767 DOI: 10.1016/j.bbrc.2017.07.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 07/04/2017] [Indexed: 11/30/2022]
Abstract
The interplay between highly pathogenic avian influenza (HPAI) H5N1 virus and immune cells has been extensively studied for years, as host immune components are thought to play significant roles in promoting the systemic spread of the virus and responsible for cytokine storm. Previous studies suggested that the interaction of B cells and monocytes could promote HPAI H5N1 infection by enhancing avian influenza virus receptor expression. In this study, we further investigate the relationship between the HPAI H5N1 virus, activated B cells, and DC-SIGN expression. DC-SIGN has been described as an important factor for mediating various types of viral infection. Here, we first demonstrate that HPAI H5N1 infection could induce an activation of B cells, which was associated with DC-SIGN expression. Using CD40L and recombinant IL-4 for B cell stimulation, we determined that DC-SIGN expressed on activated B cells was able to enhance its susceptibility to HPAI H5N1 infection. Our findings uncover the interplay between this H5N1 virus and B cells and provide important information in understanding how the virus overcomes our immune system, contributing to its unusual immunopathogenesis.
Collapse
Affiliation(s)
- Prasit Na-Ek
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Jutarat Thewsoongnoen
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Maytawan Thanunchai
- Department of Clinical Pathology, Faculty of Medicine Vajira Hospital, Navamindradhiraj University, Bangkok, Thailand
| | - Suwimon Wiboon-Ut
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Noppadol Sa-Ard-Iam
- Department of Periodontology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
| | - Rangsini Mahanonda
- Department of Periodontology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
| | | |
Collapse
|
27
|
Achinko DA, Dormer A, Narayanan M, Norman EF, Abbas M. Identification of genetic pathways driving Ebola virus disease in humans and targets for therapeutic intervention. F1000Res 2016. [DOI: 10.12688/f1000research.9778.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Introduction: LCK gene, also known as lymphocyte-specific proto-oncogene, is expressed in lymphocytes, and associated with coordinated expression of MHC class I and II in response to physiological stimuli, mediated through a combined interaction of promoters, suppressors, and enhancers. Differential usage of LCK promoters, transcribes dysfunctional transcript variants leading to leukemogenesis and non-induction of MHC class I gene variants. Viruses use C-type lectins, like CD209, to penetrate the cell, and inhibit Pattern Recognition Receptors (PRR), hence evading immune destruction. Given that Ebolavirus (EBOV) disease burden could result from a dysfunctional LCK pathway, identification of the genetic pathway leading to proper immune induction is a major priority. Methods: Data for EBOV related virus samples were obtained from Gene Expression Omnibus database and RMEAN information per gene per sample were entered into a table of values. R software v.3.3.1 was used to process differential expression patterns across samples for LCK, CD209 and immune-related genes. Principal component analysis (PCA) using ggbiplot v.0.55 was used to explain the variance across samples. Results: Data analyses identified three viral clusters based on transmission patterns as follows: LCK-CD209 dependent, LCK-dependent specific to EBOV, and CD209 dependent. Compared to HLA class II gene variants, HLA class I (A, B and C) variants were <2 fold expressed, especially for EBOV samples. PCA analyses classified TYRO3, TBK1 and LCK genes independent of the data, leading to identification of a possible pathway involving LCK, IL2, PI3k, TBK1, TYRO3 and MYB genes with downstream induction of immune T-cells. Discussion: This is the first study undertaken to understand the non-functional immune pathway, leading to EBOV disease pathogenesis and high fatality rates. Our lab currently exploits, through cutting edge genetic technology to understand the interplay of identified genes required for proper immune induction. This will guide antiviral therapy and possible markers for viral disease identification during outbreaks.
Collapse
|
28
|
Santarelli R, Granato M, Pentassuglia G, Lacconi V, Gilardini Montani MS, Gonnella R, Tafani M, Torrisi MR, Faggioni A, Cirone M. KSHV reduces autophagy in THP-1 cells and in differentiating monocytes by decreasing CAST/calpastatin and ATG5 expression. Autophagy 2016; 12:2311-2325. [PMID: 27715410 DOI: 10.1080/15548627.2016.1235122] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We have previously shown that Kaposi sarcoma-associated herpesvirus (KSHV) impairs monocyte differentiation into dendritic cells (DCs). Macroautophagy/autophagy has been reported to be essential in such a differentiating process. Here we extended these studies and found that the impairment of DC formation by KSHV occurs through autophagy inhibition. KSHV indeed reduces CAST (calpastatin) and consequently decreases ATG5 expression in both THP-1 monocytoid cells and primary monocytes. We unveiled a new mechanism put in place by KSHV to escape from immune control. The discovery of viral immune suppressive strategies that contribute to the onset and progression of viral-associated malignancies is of fundamental importance for finding new therapeutic approaches against them.
Collapse
Affiliation(s)
- R Santarelli
- a Department of Experimental Medicine , Sapienza University of Rome , Rome , Italy
| | - M Granato
- a Department of Experimental Medicine , Sapienza University of Rome , Rome , Italy
| | - G Pentassuglia
- a Department of Experimental Medicine , Sapienza University of Rome , Rome , Italy
| | - V Lacconi
- a Department of Experimental Medicine , Sapienza University of Rome , Rome , Italy
| | | | - R Gonnella
- a Department of Experimental Medicine , Sapienza University of Rome , Rome , Italy
| | - M Tafani
- a Department of Experimental Medicine , Sapienza University of Rome , Rome , Italy
| | - M R Torrisi
- b Istituto Pasteur-Fondazione Cenci Bolognetti , Department of Clinical and Molecular Medicine , Sapienza University of Rome , Rome , Italy.,c Azienda Ospedaliera Sant'Andrea , Rome , Italy
| | - A Faggioni
- a Department of Experimental Medicine , Sapienza University of Rome , Rome , Italy
| | - M Cirone
- a Department of Experimental Medicine , Sapienza University of Rome , Rome , Italy
| |
Collapse
|
29
|
Woodham AW, Skeate JG, Sanna AM, Taylor JR, Da Silva DM, Cannon PM, Kast WM. Human Immunodeficiency Virus Immune Cell Receptors, Coreceptors, and Cofactors: Implications for Prevention and Treatment. AIDS Patient Care STDS 2016; 30:291-306. [PMID: 27410493 DOI: 10.1089/apc.2016.0100] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
In the last three decades, extensive research on human immunodeficiency virus (HIV) has highlighted its capability to exploit a variety of strategies to enter and infect immune cells. Although CD4(+) T cells are well known as the major HIV target, with infection occurring through the canonical combination of the cluster of differentiation 4 (CD4) receptor and either the C-C chemokine receptor type 5 (CCR5) or C-X-C chemokine receptor type 4 (CXCR4) coreceptors, HIV has also been found to enter other important immune cell types such as macrophages, dendritic cells, Langerhans cells, B cells, and granulocytes. Interestingly, the expression of distinct cellular cofactors partially regulates the rate in which HIV infects each distinct cell type. Furthermore, HIV can benefit from the acquisition of new proteins incorporated into its envelope during budding events. While several publications have investigated details of how HIV manipulates particular cell types or subtypes, an up-to-date comprehensive review on HIV tropism for different immune cells is lacking. Therefore, this review is meant to focus on the different receptors, coreceptors, and cofactors that HIV exploits to enter particular immune cells. Additionally, prophylactic approaches that have targeted particular molecules associated with HIV entry and infection of different immune cells will be discussed. Unveiling the underlying cellular receptors and cofactors that lead to HIV preference for specific immune cell populations is crucial in identifying novel preventative/therapeutic targets for comprehensive strategies to eliminate viral infection.
Collapse
Affiliation(s)
- Andrew W. Woodham
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California
| | - Joseph G. Skeate
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California
| | - Adriana M. Sanna
- Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California
| | - Julia R. Taylor
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California
| | - Diane M. Da Silva
- Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California
- Department of Obstetrics & Gynecology, University of Southern California, Los Angeles, California
| | - Paula M. Cannon
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California
| | - W. Martin Kast
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, California
- Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California
- Department of Obstetrics & Gynecology, University of Southern California, Los Angeles, California
| |
Collapse
|
30
|
Zaccard CR, Rinaldo CR, Mailliard RB. Linked in: immunologic membrane nanotube networks. J Leukoc Biol 2016; 100:81-94. [PMID: 26931578 DOI: 10.1189/jlb.4vmr0915-395r] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 02/01/2016] [Indexed: 01/01/2023] Open
Abstract
Membrane nanotubes, also termed tunneling nanotubes, are F-actin-based structures that can form direct cytoplasmic connections and support rapid communication between distant cells. These nanoscale conduits have been observed in diverse cell types, including immune, neuronal, stromal, cancer, and stem cells. Until recently, little was known about the mechanisms involved in membrane nanotube development in myeloid origin APCs or how membrane nanotube networks support their ability to bridge innate and adaptive immunity. New research has provided insight into the modes of induction and regulation of the immune process of "reticulation" or the development of multicellular membrane nanotube networks in dendritic cells. Preprogramming by acute type 1 inflammatory mediators at their immature stage licenses mature type 1-polarized dendritic cells to reticulate upon subsequent interaction with CD40 ligand-expressing CD4(+) Th cells. Dendritic cell reticulation can support direct antigen transfer for amplification of specific T cell responses and can be positively or negatively regulated by signals from distinct Th cell subsets. Membrane nanotubes not only enhance the ability of immature dendritic cells to sense pathogens and rapidly mobilize nearby antigen-presenting cells in the peripheral tissues but also likely support communication of pathogen-related information from mature migratory dendritic cells to resident dendritic cells in lymph nodes. Therefore, the reticulation process facilitates a coordinated multicellular response for the efficient initiation of cell-mediated adaptive immune responses. Herein, we discuss studies focused on the molecular mechanisms of membrane nanotube formation, structure, and function in the context of immunity and how pathogens, such as HIV-1, may use dendritic cell reticulation to circumvent host defenses.
Collapse
Affiliation(s)
- C R Zaccard
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pennsylvania, USA and
| | - C R Rinaldo
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pennsylvania, USA and Department of Pathology, University of Pittsburgh, Pennsylvania, USA
| | - R B Mailliard
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pennsylvania, USA and
| |
Collapse
|
31
|
Pustylnikov S, Dave RS, Khan ZK, Porkolab V, Rashad AA, Hutchinson M, Fieschi F, Chaiken I, Jain P. Short Communication: Inhibition of DC-SIGN-Mediated HIV-1 Infection by Complementary Actions of Dendritic Cell Receptor Antagonists and Env-Targeting Virus Inactivators. AIDS Res Hum Retroviruses 2016; 32:93-100. [PMID: 26383762 DOI: 10.1089/aid.2015.0184] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The DC-SIGN receptor on human dendritic cells interacts with HIV gp120 to promote both infection of antigen-presenting cells and transinfection of T cells. We hypothesized that in DC-SIGN-expressing cells, both DC-SIGN ligands such as dextrans and gp120 antagonists such as peptide triazoles would inhibit HIV infection with potential complementary antagonist effects. To test this hypothesis, we evaluated the effects of dextran (D66), isomaltooligosaccharides (D06), and several peptide triazoles (HNG156, K13, and UM15) on HIV infection of B-THP-1/DC-SIGN cells. In surface plasmon resonance competition assays, D66 (IC50 = 35.4 μM) and D06 (IC50 = 3.4 mM) prevented binding of soluble DC-SIGN to immobilized mannosylated bovine serum albumin (BSA). An efficacious dose-dependent inhibition of DC-SIGN-mediated HIV infection in both pretreatment and posttreatment settings was observed, as indicated by inhibitory potentials (EC50) [D66 (8 μM), D06 (48 mM), HNG156 (40 μM), UM15 (100 nM), and K13 (25 nM)]. Importantly, both dextrans and peptide triazoles significantly decreased HIV gag RNA levels [D66 (7-fold), D06 (13-fold), HNG156 (7-fold), K-13 (3-fold), and UM15 (6-fold)]. Interestingly, D06 at the highest effective concentration showed a 14-fold decrease of infection, while its combination with 50 μM HNG156 showed a 26-fold decrease. Hence, these compounds can combine to inactivate the viruses and suppress DC-SIGN-mediated virus-cell interaction that as shown earlier leads to dendritic cell HIV infection and transinfection dependent on the DC-SIGN receptor.
Collapse
Affiliation(s)
- Sergey Pustylnikov
- Novosibirsk Tuberculosis Research Institute, Novosibirsk, Russia
- State Research Center of Virology and Biotechnology “Vector,” Koltsovo, Russia
- Department of Microbiology and Immunology, and the Institute for Molecular Medicine & Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Rajnish S. Dave
- Department of Microbiology and Immunology, and the Institute for Molecular Medicine & Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Zafar K. Khan
- Department of Microbiology and Immunology, and the Institute for Molecular Medicine & Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Vanessa Porkolab
- University Grenoble Alpes, Institut de Biologie Structurale, Grenoble, France
- CNRS, IBS, Grenoble, France
- CEA, IBS, Grenoble, France
| | - Adel A. Rashad
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Matthew Hutchinson
- Department of Microbiology and Immunology, and the Institute for Molecular Medicine & Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Frank Fieschi
- University Grenoble Alpes, Institut de Biologie Structurale, Grenoble, France
- CNRS, IBS, Grenoble, France
- CEA, IBS, Grenoble, France
| | - Irwin Chaiken
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Pooja Jain
- Department of Microbiology and Immunology, and the Institute for Molecular Medicine & Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
| |
Collapse
|
32
|
Kumar NA, Cheong K, Powell DR, da Fonseca Pereira C, Anderson J, Evans VA, Lewin SR, Cameron PU. The role of antigen presenting cells in the induction of HIV-1 latency in resting CD4(+) T-cells. Retrovirology 2015; 12:76. [PMID: 26362311 PMCID: PMC4567795 DOI: 10.1186/s12977-015-0204-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 09/01/2015] [Indexed: 12/24/2022] Open
Abstract
Background Combination antiretroviral therapy (cART) is able to control HIV-1 viral replication, however long-lived latent infection in resting memory CD4+ T-cells persist. The mechanisms for establishment and maintenance of latent infection in resting memory CD4+ T-cells remain unclear. Previously we have shown that HIV-1 infection of resting CD4+ T-cells co-cultured with CD11c+ myeloid dendritic cells (mDC) produced a population of non-proliferating T-cells with latent infection. Here we asked whether different antigen presenting cells (APC), including subpopulations of DC and monocytes, were able to induce post-integration latent infection in resting CD4+ T-cells, and examined potential cell interactions that may be involved using RNA-seq. Results mDC (CD1c+), SLAN+ DC and CD14+ monocytes were most efficient in stimulating proliferation of CD4+ T-cells during syngeneic culture and in generating post-integration latent infection in non-proliferating CD4+ T-cells following HIV-1 infection of APC-T cell co-cultures. In comparison, plasmacytoid DC (pDC) and B-cells did not induce latent infection in APC-T-cell co-cultures. We compared the RNA expression profiles of APC subpopulations that could and could not induce latency in non-proliferating CD4+ T-cells. Gene expression analysis, comparing the CD1c+ mDC, SLAN+ DC and CD14+ monocyte subpopulations to pDC identified 53 upregulated genes that encode proteins expressed on the plasma membrane that could signal to CD4+ T-cells via cell–cell interactions (32 genes), immune checkpoints (IC) (5 genes), T-cell activation (9 genes), regulation of apoptosis (5 genes), antigen presentation (1 gene) and through unknown ligands (1 gene). Conclusions APC subpopulations from the myeloid lineage, specifically mDC subpopulations and CD14+ monocytes, were able to efficiently induce post-integration HIV-1 latency in non-proliferating CD4+ T-cells in vitro. Inhibition of key pathways involved in mDC-T-cell interactions and HIV-1 latency may provide novel targets to eliminate HIV-1 latency. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0204-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Nitasha A Kumar
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, VIC, 3004, Australia. .,Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, 3004, Australia. .,Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, 3010, Australia.
| | - Karey Cheong
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, VIC, 3004, Australia. .,Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, 3004, Australia. .,Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, 3010, Australia.
| | - David R Powell
- Victorian Life Science Computational Initiative, Parkville, 3010, Australia. .,Monash Bioinformatics Platform, Monash University, Clayton, 3800, Australia.
| | | | - Jenny Anderson
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, VIC, 3004, Australia. .,Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, 3004, Australia. .,Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, 3010, Australia.
| | - Vanessa A Evans
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, VIC, 3004, Australia. .,Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, 3004, Australia. .,Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, 3010, Australia.
| | - Sharon R Lewin
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, VIC, 3004, Australia. .,Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, 3004, Australia. .,Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, 3010, Australia.
| | - Paul U Cameron
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, VIC, 3004, Australia. .,Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, 3004, Australia. .,Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, 3010, Australia.
| |
Collapse
|
33
|
Weinberg A, Muresan P, Richardson KM, Fenton T, Dominguez T, Bloom A, Watts DH, Abzug MJ, Nachman SA, Levin MJ. Determinants of vaccine immunogenicity in HIV-infected pregnant women: analysis of B and T cell responses to pandemic H1N1 monovalent vaccine. PLoS One 2015; 10:e0122431. [PMID: 25874544 PMCID: PMC4395240 DOI: 10.1371/journal.pone.0122431] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 02/11/2015] [Indexed: 11/19/2022] Open
Abstract
Influenza infections have high frequency and morbidity in HIV-infected pregnant women, underscoring the importance of vaccine-conferred protection. To identify the factors that determine vaccine immunogenicity in this group, we characterized the relationship of B- and T-cell responses to pandemic H1N1 (pH1N1) vaccine with HIV-associated immunologic and virologic characteristics. pH1N1 and seasonal-H1N1 (sH1N1) antibodies were measured in 119 HIV-infected pregnant women after two double-strength pH1N1 vaccine doses. pH1N1-IgG and IgA B-cell FluoroSpot, pH1N1- and sH1N1-interferon γ (IFNγ) and granzyme B (GrB) T-cell FluoroSpot, and flow cytometric characterization of B- and T-cell subsets were performed in 57 subjects. pH1N1-antibodies increased after vaccination, but less than previously described in healthy adults. pH1N1-IgG memory B cells (Bmem) increased, IFNγ-effector T-cells (Teff) decreased, and IgA Bmem and GrB Teff did not change. pH1N1-antibodies and Teff were significantly correlated with each other and with sH1N1-HAI and Teff, respectively, before and after vaccination. pH1N1-antibody responses to the vaccine significantly increased with high proportions of CD4+, low CD8+ and low CD8+HLADR+CD38+ activated (Tact) cells. pH1N1-IgG Bmem responses increased with high proportions of CD19+CD27+CD21- activated B cells (Bact), high CD8+CD39+ regulatory T cells (Treg), and low CD19+CD27-CD21- exhausted B cells (Bexhaust). IFNγ-Teff responses increased with low HIV plasma RNA, CD8+HLADR+CD38+ Tact, CD4+FoxP3+ Treg and CD19+IL10+ Breg. In conclusion, pre-existing antibody and Teff responses to sH1N1 were associated with increased responses to pH1N1 vaccination in HIV-infected pregnant women suggesting an important role for heterosubtypic immunologic memory. High CD4+% T cells were associated with increased, whereas high HIV replication, Tact and Bexhaust were associated with decreased vaccine immunogenicity. High Treg increased antibody responses but decreased Teff responses to the vaccine. The proportions of immature and transitional B cells did not affect the responses to vaccine. Increased Bact were associated with high Bmem responses to the vaccine.
Collapse
Affiliation(s)
- Adriana Weinberg
- University of Colorado Anschutz Medical Center, Aurora, Colorado, United States of America
- * E-mail:
| | - Petronella Muresan
- Statistical and Data Analysis Center, Center for Biostatistics in AIDS Research, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Kelly M. Richardson
- University of Colorado Anschutz Medical Center, Aurora, Colorado, United States of America
| | - Terence Fenton
- Statistical and Data Analysis Center, Center for Biostatistics in AIDS Research, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Teresa Dominguez
- University of Colorado Anschutz Medical Center, Aurora, Colorado, United States of America
| | - Anthony Bloom
- Frontier Science and Technology Research Foundation, Buffalo, New York, United States of America
| | - D. Heather Watts
- Maternal and Pediatric Infectious Disease Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, United States of America
| | - Mark J. Abzug
- University of Colorado Anschutz Medical Center, Aurora, Colorado, United States of America
| | - Sharon A. Nachman
- State University of New York Health Science Center at Stony Brook, Stony Brook, New York, United States of America
| | - Myron J. Levin
- University of Colorado Anschutz Medical Center, Aurora, Colorado, United States of America
| | | |
Collapse
|
34
|
Characterization of functional antibody and memory B-cell responses to pH1N1 monovalent vaccine in HIV-infected children and youth. PLoS One 2015; 10:e0118567. [PMID: 25785995 PMCID: PMC4364897 DOI: 10.1371/journal.pone.0118567] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 01/20/2015] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES We investigated immune determinants of antibody responses and B-cell memory to pH1N1 vaccine in HIV-infected children. METHODS Ninety subjects 4 to <25 years of age received two double doses of pH1N1 vaccine. Serum and cells were frozen at baseline, after each vaccination, and at 28 weeks post-immunization. Hemagglutination inhibition (HAI) titers, avidity indices (AI), B-cell subsets, and pH1N1 IgG and IgA antigen secreting cells (ASC) were measured at baseline and after each vaccination. Neutralizing antibodies and pH1N1-specific Th1, Th2 and Tfh cytokines were measured at baseline and post-dose 1. RESULTS At entry, 26 (29%) subjects had pH1N1 protective HAI titers (≥1:40). pH1N1-specific HAI, neutralizing titers, AI, IgG ASC, IL-2 and IL-4 increased in response to vaccination (p<0.05), but IgA ASC, IL-5, IL-13, IL-21, IFNγ and B-cell subsets did not change. Subjects with baseline HAI ≥1:40 had significantly greater increases in IgG ASC and AI after immunization compared with those with HAI <1:40. Neutralizing titers and AI after vaccination increased with older age. High pH1N1 HAI responses were associated with increased IgG ASC, IFNγ, IL-2, microneutralizion titers, and AI. Microneutralization titers after vaccination increased with high IgG ASC and IL-2 responses. IgG ASC also increased with high IFNγ responses. CD4% and viral load did not predict the immune responses post-vaccination, but the B-cell distribution did. Notably, vaccine immunogenicity increased with high CD19+CD21+CD27+% resting memory, high CD19+CD10+CD27+% immature activated, low CD19+CD21-CD27-CD20-% tissue-like, low CD19+CD21-CD27-CD20-% transitional and low CD19+CD38+HLADR+% activated B-cell subsets. CONCLUSIONS HIV-infected children on HAART mount a broad B-cell memory response to pH1N1 vaccine, which was higher for subjects with baseline HAI≥1:40 and increased with age, presumably due to prior exposure to pH1N1 or to other influenza vaccination/infection. The response to the vaccine was dependent on B-cell subset distribution, but not on CD4 counts or viral load. TRIAL REGISTRATION ClinicalTrials.gov NCT00992836.
Collapse
|
35
|
Campbell DM, Rappocciolo G, Jenkins FJ, Rinaldo CR. Dendritic cells: key players in human herpesvirus 8 infection and pathogenesis. Front Microbiol 2014; 5:452. [PMID: 25221546 PMCID: PMC4148009 DOI: 10.3389/fmicb.2014.00452] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 08/11/2014] [Indexed: 11/13/2022] Open
Abstract
Human herpesvirus 8 (HHV-8; Kaposi's sarcoma-associated herpesvirus) is an oncogenic gammaherpesvirus that primarily infects cells of the immune and vascular systems. HHV-8 interacts with and targets professional antigen presenting cells and influences their function. Infection alters the maturation, antigen presentation, and immune activation capabilities of certain dendritic cells (DC) despite non-robust lytic replication in these cells. DC sustains a low level of antiviral functionality during HHV-8 infection in vitro. This may explain the ability of healthy individuals to effectively control this virus without disease. Following an immune compromising event, such as organ transplantation or human immunodeficiency virus type 1 infection, a reduced cellular antiviral response against HHV-8 compounded with skewed DC cytokine production and antigen presentation likely contributes to the development of HHV-8 associated diseases, i.e., Kaposi's sarcoma and certain B cell lymphomas. In this review we focus on the role of DC in the establishment of HHV-8 primary and latent infection, the functional state of DC during HHV-8 infection, and the current understanding of the factors influencing virus-DC interactions in the context of HHV-8-associated disease.
Collapse
Affiliation(s)
- Diana M Campbell
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh Pittsburgh, PA, USA
| | - Giovanna Rappocciolo
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh Pittsburgh, PA, USA
| | - Frank J Jenkins
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh Pittsburgh, PA, USA ; Department of Pathology, School of Medicine, University of Pittsburgh Pittsburgh, PA, USA
| | - Charles R Rinaldo
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh Pittsburgh, PA, USA ; Department of Pathology, School of Medicine, University of Pittsburgh Pittsburgh, PA, USA
| |
Collapse
|
36
|
Abstract
A small percentage of HIV-infected subjects (2 to 15%) are able to control disease progression for many years without antiretroviral therapy. Years of intense studies of virologic and immunologic mechanisms of disease control in such individuals yielded a number of possible host genes that could be responsible for the preservation of immune functions, from immune surveillance genes, chemokines, or their receptors to anti-HIV restriction factors. A recent mBio paper by Rappocciolo et al. (G. Rappocciolo, M. Jais, P. Piazza, T. A. Reinhart, S. J. Berendam, L. Garcia-Exposito, P. Gupta, and C. R. Rinaldo, mBio 5:e01031-13, 2014) describes another potential factor controlling disease progression: cholesterol levels in antigen-presenting cells. In this commentary, we provide a brief background of the role of cholesterol in HIV infection, discuss the results of the study by Rappocciolo et al., and present the implications of their findings.
Collapse
|
37
|
Kardava L, Moir S, Shah N, Wang W, Wilson R, Buckner CM, Santich BH, Kim LJY, Spurlin EE, Nelson AK, Wheatley AK, Harvey CJ, McDermott AB, Wucherpfennig KW, Chun TW, Tsang JS, Li Y, Fauci AS. Abnormal B cell memory subsets dominate HIV-specific responses in infected individuals. J Clin Invest 2014; 124:3252-62. [PMID: 24892810 DOI: 10.1172/jci74351] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 04/10/2014] [Indexed: 11/17/2022] Open
Abstract
Recently, several neutralizing anti-HIV antibodies have been isolated from memory B cells of HIV-infected individuals. Despite extensive evidence of B cell dysfunction in HIV disease, little is known about the cells from which these rare HIV-specific antibodies originate. Accordingly, we used HIV envelope gp140 and CD4 or coreceptor (CoR) binding site (bs) mutant probes to evaluate HIV-specific responses in peripheral blood B cells of HIV-infected individuals at various stages of infection. In contrast to non-HIV responses, HIV-specific responses against gp140 were enriched within abnormal B cells, namely activated and exhausted memory subsets, which are largely absent in the blood of uninfected individuals. Responses against the CoRbs, which is a poorly neutralizing epitope, arose early, whereas those against the well-characterized neutralizing epitope CD4bs were delayed and infrequent. Enrichment of the HIV-specific response within resting memory B cells, the predominant subset in uninfected individuals, did occur in certain infected individuals who maintained low levels of plasma viremia and immune activation with or without antiretroviral therapy. The distribution of HIV-specific responses among memory B cell subsets was corroborated by transcriptional analyses. Taken together, our findings provide valuable insight into virus-specific B cell responses in HIV infection and demonstrate that memory B cell abnormalities may contribute to the ineffectiveness of the antibody response in infected individuals.
Collapse
|
38
|
Abstract
HIV-1-infected nonprogressors (NP) inhibit disease progression for years without antiretroviral therapy. Defining the mechanisms for this resistance to disease progression could be important in determining strategies for controlling HIV-1 infection. Here we show that two types of professional antigen-presenting cells (APC), i.e., dendritic cells (DC) and B lymphocytes, from NP lacked the ability to mediate HIV-1 trans infection of CD4+ T cells. In contrast, APC from HIV-1-infected progressors (PR) and HIV-1-seronegative donors (SN) were highly effective in mediating HIV-1 trans infection. Direct cis infection of T cells with HIV-1 was comparably efficient among NP, PR, and SN. Lack of HIV-1 trans infection in NP was linked to lower cholesterol levels and an increase in the levels of the reverse cholesterol transporter ABCA1 (ATP-binding cassette transporter A1) in APC but not in T cells. Moreover, trans infection mediated by APC from NP could be restored by reconstitution of cholesterol and by inhibiting ABCA1 by mRNA interference. Importantly, this appears to be an inherited trait, as it was evident in APC obtained from NP prior to their primary HIV-1 infection. The present study demonstrates a new mechanism wherein enhanced lipid metabolism in APC results in remarkable control of HIV-1 trans infection that directly relates to lack of HIV-1 disease progression. HIV-1 can be captured by antigen-presenting cells (APC) such as dendritic cells and transferred to CD4 helper T cells, which results in greatly enhanced viral replication by a mechanism termed trans infection. A small percentage of HIV-1-infected persons are able to control disease progression for many years without antiretroviral therapy. In our study, we linked this lack of disease progression to a profound inability of APC from these individuals to trans infect T cells. This effect was due to altered lipid metabolism in their APC, which appears to be an inherited trait. These results provide a basis for therapeutic interventions to control of HIV-1 infection through modulation of cholesterol metabolism.
Collapse
|
39
|
Pustylnikov S, Sagar D, Jain P, Khan ZK. Targeting the C-type lectins-mediated host-pathogen interactions with dextran. JOURNAL OF PHARMACY & PHARMACEUTICAL SCIENCES : A PUBLICATION OF THE CANADIAN SOCIETY FOR PHARMACEUTICAL SCIENCES, SOCIETE CANADIENNE DES SCIENCES PHARMACEUTIQUES 2014; 17:371-92. [PMID: 25224349 PMCID: PMC5553543 DOI: 10.18433/j3n590] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Dextran, the α-1,6-linked glucose polymer widely used in biology and medicine, promises new applications. Linear dextran applied as a blood plasma substitute demonstrates a high rate of biocompatibility. Dextran is present in foods, drugs, and vaccines and in most cases is applied as a biologically inert substance. In this review we analyze dextran's cellular uptake principles, receptor specificity and, therefore, its ability to interfere with pathogen-lectin interactions: a promising basis for new antimicrobial strategies. Dextran-binding receptors in humans include the DC-SIGN (dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin) family receptors: DC-SIGN (CD209) and L-SIGN (the liver and lymphatic endothelium homologue of DC-SIGN), the mannose receptor (CD206), and langerin. These receptors take part in the uptake of pathogens by dendritic cells and macrophages and may also participate in the modulation of immune responses, mostly shown to be beneficial for pathogens per se rather than host(s). It is logical to predict that owing to receptor-specific interactions, dextran or its derivatives can interfere with these immune responses and improve infection outcome. Recent data support this hypothesis. We consider dextran a promising molecule for the development of lectin-glycan interaction-blocking molecules (such as DC-SIGN inhibitors) that could be applied in the treatment of diseases including tuberculosis, influenza, hepatitis B and C, human immunodeficiency virus infection and AIDS, etc. Dextran derivatives indeed change the pathology of infections dependent on DC-SIGN and mannose receptors. Complete knowledge of specific dextran-lectin interactions may also be important for development of future dextran applications in biological research and medicine.
Collapse
Affiliation(s)
- Sergey Pustylnikov
- Group of Molecular Biology Research, Novosibirsk Tuberculosis Research Institute, Novosibirsk, Russia. Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | | | | | | |
Collapse
|
40
|
Van Breedam W, Pöhlmann S, Favoreel HW, de Groot RJ, Nauwynck HJ. Bitter-sweet symphony: glycan-lectin interactions in virus biology. FEMS Microbiol Rev 2013; 38:598-632. [PMID: 24188132 PMCID: PMC7190080 DOI: 10.1111/1574-6976.12052] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 09/27/2013] [Accepted: 10/14/2013] [Indexed: 01/01/2023] Open
Abstract
Glycans are carbohydrate modifications typically found on proteins or lipids, and can act as ligands for glycan-binding proteins called lectins. Glycans and lectins play crucial roles in the function of cells and organs, and in the immune system of animals and humans. Viral pathogens use glycans and lectins that are encoded by their own or the host genome for their replication and spread. Recent advances in glycobiological research indicate that glycans and lectins mediate key interactions at the virus-host interface, controlling viral spread and/or activation of the immune system. This review reflects on glycan–lectin interactions in the context of viral infection and antiviral immunity. A short introduction illustrates the nature of glycans and lectins, and conveys the basic principles of their interactions. Subsequently, examples are discussed highlighting specific glycan–lectin interactions and how they affect the progress of viral infections, either benefiting the host or the virus. Moreover, glycan and lectin variability and their potential biological consequences are discussed. Finally, the review outlines how recent advances in the glycan–lectin field might be transformed into promising new approaches to antiviral therapy.
Collapse
Affiliation(s)
- Wander Van Breedam
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | | | | | | | | |
Collapse
|
41
|
Petrara MR, Freguja R, Gianesin K, Zanchetta M, De Rossi A. Epstein-Barr virus-driven lymphomagenesis in the context of human immunodeficiency virus type 1 infection. Front Microbiol 2013; 4:311. [PMID: 24151490 PMCID: PMC3799006 DOI: 10.3389/fmicb.2013.00311] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 09/28/2013] [Indexed: 12/12/2022] Open
Abstract
Epstein-Barr virus (EBV) is a ubiquitous human γ-herpes virus which establishes a life-long asymptomatic infection in immunocompetent hosts. In human immunodeficiency virus type 1 (HIV-1) infected patients, the impaired immunosurveillance against EBV may favor the development of EBV-related diseases, ranging from lymphoproliferative disorders to B cell non-Hodgkin's lymphomas (NHL). Antiretroviral therapy (ART) has significantly modified the natural course of HIV-1 infection, resulting in decreased HIV-1 plasmaviremia, increased CD4 lymphocytes, and decreased opportunistic infections, indicating a restoration of immune functions. However, the impact of ART appears to be less favorable on EBV-related malignancies than on other AIDS-defining tumors, such as Kaposi's sarcoma, and NHL remains the most common cancer during the ART era. EBV-driven tumors are associated with selective expression of latent oncogenic proteins, but uncontrolled lytic cycle with virus replication and/or reactivation may favor cell transformation, at least in the early phases. Several host's factors may promote EBV reactivation and replication; besides immunodepression, inflammation/chronic immune stimulation may play an important role. Microbial pathogen-associated molecular patterns and endogenous damage-associated molecular patterns, through Toll-like receptors, activate the immune system and may promote EBV reactivation and/or polyclonal expansion of EBV-infected cells. A body of evidence suggests that chronic immune stimulation is a hallmark of HIV-1 pathogenesis and may persist even in ART-treated patients. This review focuses on lymphomagenesis driven by EBV both in the context of the natural history of HIV-1 infection and in ART-treated patients. Understanding the mechanisms involved in the expansion of EBV-infected cells is a premise for the identification of prognostic markers of EBV-associated malignancies.
Collapse
Affiliation(s)
- Maria R Petrara
- Viral Oncology Unit and AIDS Reference Center, Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, University of Padova Padova, Italy
| | | | | | | | | |
Collapse
|
42
|
Mailliard RB, Smith KN, Fecek RJ, Rappocciolo G, Nascimento EJM, Marques ET, Watkins SC, Mullins JI, Rinaldo CR. Selective induction of CTL helper rather than killer activity by natural epitope variants promotes dendritic cell-mediated HIV-1 dissemination. THE JOURNAL OF IMMUNOLOGY 2013; 191:2570-80. [PMID: 23913962 DOI: 10.4049/jimmunol.1300373] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The ability of HIV-1 to rapidly accumulate mutations provides the virus with an effective means of escaping CD8(+) CTL responses. In this study, we describe how subtle alterations in CTL epitopes expressed by naturally occurring HIV-1 variants can result in an incomplete escape from CTL recognition, providing the virus with a selective advantage. Rather than paralyzing the CTL response, these epitope modifications selectively induce the CTL to produce proinflammatory cytokines in the absence of target killing. Importantly, instead of dampening the immune response through CTL elimination of variant Ag-expressing immature dendritic cells (DC), a positive CTL-to-DC immune feedback loop dominates whereby the immature DC differentiate into mature proinflammatory DC. Moreover, these CTL-programmed DC exhibit a superior capacity to mediate HIV-1 trans-infection of T cells. This discordant induction of CTL helper activity in the absence of killing most likely contributes to the chronic immune activation associated with HIV-1 infection, and can be used by HIV-1 to promote viral dissemination and persistence. Our findings highlight the need to address the detrimental potential of eliciting dysfunctional cross-reactive memory CTL responses when designing and implementing anti-HIV-1 immunotherapies.
Collapse
Affiliation(s)
- Robbie B Mailliard
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Rinaldo CR. HIV-1 Trans Infection of CD4(+) T Cells by Professional Antigen Presenting Cells. SCIENTIFICA 2013; 2013:164203. [PMID: 24278768 PMCID: PMC3820354 DOI: 10.1155/2013/164203] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 04/09/2013] [Indexed: 06/02/2023]
Abstract
Since the 1990s we have known of the fascinating ability of a complex set of professional antigen presenting cells (APCs; dendritic cells, monocytes/macrophages, and B lymphocytes) to mediate HIV-1 trans infection of CD4(+) T cells. This results in a burst of virus replication in the T cells that is much greater than that resulting from direct, cis infection of either APC or T cells, or trans infection between T cells. Such APC-to-T cell trans infection first involves a complex set of virus subtype, attachment, entry, and replication patterns that have many similarities among APC, as well as distinct differences related to virus receptors, intracellular trafficking, and productive and nonproductive replication pathways. The end result is that HIV-1 can sequester within the APC for several days and be transmitted via membrane extensions intracellularly and extracellularly to T cells across the virologic synapse. Virus replication requires activated T cells that can develop concurrently with the events of virus transmission. Further research is essential to fill the many gaps in our understanding of these trans infection processes and their role in natural HIV-1 infection.
Collapse
Affiliation(s)
- Charles R. Rinaldo
- Department of Infectious Diseases and Microbiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA 15261, USA
| |
Collapse
|
44
|
Giahi L, Elmadfa I, Hoseini M, Klein P. Heat-inactivatedLactobacillus rhamnosusandLactobacillus delbrueckiiinduce efficient maturation and differential cytokine production in human monocyte derived dendritic cells. FOOD AGR IMMUNOL 2013. [DOI: 10.1080/09540105.2011.651445] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
|
45
|
Abstract
The retrovirus family contains several important human and animal pathogens, including the human immunodeficiency virus (HIV), the causative agent of acquired immunodeficiency syndrome (AIDS). Studies with retroviruses were instrumental to our present understanding of the cellular entry of enveloped viruses in general. For instance, studies with alpharetroviruses defined receptor engagement, as opposed to low pH, as a trigger for the envelope protein-driven membrane fusion. The insights into the retroviral entry process allowed the generation of a new class of antivirals, entry inhibitors, and these therapeutics are at present used for treatment of HIV/AIDS. In this chapter, we will summarize key concepts established for entry of avian sarcoma and leukosis virus (ASLV), a widely used model system for retroviral entry. We will then review how foamy virus and HIV, primate- and human retroviruses, enter target cells, and how the interaction of the viral and cellular factors involved in the cellular entry of these viruses impacts viral tropism, pathogenesis and approaches to therapy and vaccine development.
Collapse
|
46
|
García-Pérez BE, De la Cruz-López JJ, Castañeda-Sánchez JI, Muñóz-Duarte AR, Hernández-Pérez AD, Villegas-Castrejón H, García-Latorre E, Caamal-Ley A, Luna-Herrera J. Macropinocytosis is responsible for the uptake of pathogenic and non-pathogenic mycobacteria by B lymphocytes (Raji cells). BMC Microbiol 2012; 12:246. [PMID: 23113903 PMCID: PMC3559283 DOI: 10.1186/1471-2180-12-246] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Accepted: 10/12/2012] [Indexed: 12/18/2022] Open
Abstract
Background The classical roles of B cells include the production of antibodies and cytokines and the generation of immunological memory, these being key factors in the adaptive immune response. However, their role in innate immunity is currently being recognised. Traditionally, B cells have been considered non-phagocytic cells; therefore, the uptake of bacteria by B cells is not extensively documented. In this study, we analysed some of the features of non-specific bacterial uptake by B lymphocytes from the Raji cell line. In our model, B cells were infected with Mycobacterium tuberculosis (MTB), Mycobacterium smegmatis (MSM), and Salmonella typhimurium (ST). Results Our observations revealed that the Raji B cells were readily infected by the three bacteria that were studied. All of the infections induced changes in the cellular membrane during bacterial internalisation. M. smegmatis and S. typhimurium were able to induce important membrane changes that were characterised by abundant filopodia and lamellipodia formation. These membrane changes were driven by actin cytoskeletal rearrangements. The intracellular growth of these bacteria was also controlled by B cells. M. tuberculosis infection also induced actin rearrangement-driven membrane changes; however, the B cells were not able to control this infection. The phorbol 12-myristate 13-acetate (PMA) treatment of B cells induced filopodia and lamellipodia formation, the production of spacious vacuoles (macropinosomes), and the fluid-phase uptake that is characteristic of macropinocytosis. S. typhimurium infection induced the highest fluid-phase uptake, although both mycobacteria also induced fluid uptake. A macropinocytosis inhibitor such as amiloride was used and abolished the bacterial uptake and the fluid-phase uptake that is triggered during the bacterial infection. Conclusions Raji B cells can internalise S. typhimurium and mycobacteria through an active process, such as macropinocytosis, although the resolution of the infection depends on factors that are inherent in the virulence of each pathogen.
Collapse
Affiliation(s)
- Blanca Estela García-Pérez
- Immunology Department, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México, D,F, México
| | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Abstract
The discovery of host-encoded gene products that sense molecular patterns in infectious microbes, and the demonstration of their role in triggering innate and adaptive immune responses, has been a key milestone in our understanding of immunology. Twenty-three years after Janeway first outlined the fundamental concepts of the 'pattern recognition' model, and 15 years since the identification of Toll-like receptors (TLRs) as pattern recognition receptors (PRRs), new insights continue to be revealed, and questions remain. For example, innate immune responses to microbes that are mediated by PRRs have historically been viewed as the domain of innate immune cell populations such as dendritic cells and macrophages. New evidence, however, has pointed to the role of B-cell-intrinsic TLR activation in shaping antibody responses. These studies have revealed that TLRs regulate a complex transcriptional network that controls multiple steps in the development of antigen-specific antibodies. This review covers these recent developments regarding the role of TLRs in B-cell gene expression and function in vitro and in vivo, and highlights the remaining challenges in the field, with particular emphasis on the role of TLRs in antibody responses to viral infection. A more complete understanding of how TLRs regulate antibody responses will lead to improved vaccine design.
Collapse
Affiliation(s)
- Edward P Browne
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| |
Collapse
|
48
|
Baan E, de Ronde A, Luchters S, Vyankandondera J, Lange JM, Pollakis G, Paxton WA. HIV type 1 mother-to-child transmission facilitated by distinctive glycosylation sites in the gp120 envelope glycoprotein. AIDS Res Hum Retroviruses 2012; 28:715-24. [PMID: 21916748 DOI: 10.1089/aid.2011.0023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) characteristics associated with mother-to-child transmission (MTCT) are still poorly understood. We studied a cohort of 30 mothers from Rwanda infected with HIV-1 subtype A or C viruses of whom seven infected their children either during gestation or soon after birth. CD4 counts and viral load did not significantly differ between nontransmitting mother (NTM) versus transmitting mother (TM) groups. In contrast to earlier studies we not only analyzed and compared the genotypic characteristics of the V1-V5 region of the gp120 envelope of viruses found in TM and their infected children, but also included data from the NTM. No differences were found with respect to length and number of potential N-glycosylation sites (PNGS) in the V1-V2 and the V1-V5 region. We identified that viruses with a PNGS on positions AA234 and AA339 were preferably transmitted and that viruses with PNGS-N295 showed a disadvantage in transmission. We also showed that the frequency of PNGS-N339 in the viruses of TM and infected children was significantly higher than the frequency in NTM in our cohort and in viruses undergoing sexual transmission while the frequency of PNGS-N295 in children was significantly lower than the frequency in TM and acute horizontal infections. Collectively, our results provide evidence that the presence of the PNGS-N339 site and absence of the PNGS-N295 site in the gp120 envelope confers an advantage to HIV-1 when considering MTCT.
Collapse
Affiliation(s)
- Elly Baan
- Laboratory of Experimental Virology, Department of Medical Microbiology, Centre for Infection and Immunity Amsterdam (CINIMA), Academic Medical Centre of the University of Amsterdam, Amsterdam, the Netherlands
| | - Anthony de Ronde
- Laboratory of Experimental Virology, Department of Medical Microbiology, Centre for Infection and Immunity Amsterdam (CINIMA), Academic Medical Centre of the University of Amsterdam, Amsterdam, the Netherlands
| | - Stanley Luchters
- IATEC, International Antiviral Therapy Evaluation Center, Amsterdam, the Netherlands
| | - Joseph Vyankandondera
- CHUK, Centre Hospitalier Universitaire de Kigali and Belgian Technical Cooperation, Kigali, Rwanda
| | - Joep M. Lange
- IATEC, International Antiviral Therapy Evaluation Center, Amsterdam, the Netherlands
| | - Georgios Pollakis
- Laboratory of Experimental Virology, Department of Medical Microbiology, Centre for Infection and Immunity Amsterdam (CINIMA), Academic Medical Centre of the University of Amsterdam, Amsterdam, the Netherlands
| | - William A. Paxton
- Laboratory of Experimental Virology, Department of Medical Microbiology, Centre for Infection and Immunity Amsterdam (CINIMA), Academic Medical Centre of the University of Amsterdam, Amsterdam, the Netherlands
| |
Collapse
|
49
|
Wang Y, Whittall T, Rahman D, Bunnik EM, Vaughan R, Schøller J, Bergmeier LA, Montefiori D, Singh M, Schuitemaker H, Lehner T. The role of innate APOBEC3G and adaptive AID immune responses in HLA-HIV/SIV immunized SHIV infected macaques. PLoS One 2012; 7:e34433. [PMID: 22514633 PMCID: PMC3326050 DOI: 10.1371/journal.pone.0034433] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 02/28/2012] [Indexed: 01/27/2023] Open
Abstract
The AID/APOBEC family (activation induced deaminase/apolipoprotein B mRNA editing cytokine deaminase) in B cells play important roles in adaptive and innate immunity. Whereas APOBEC3G has been studied in CD4+ T cells and myeloid cells its functional potential in B cells has received little attention. AID combines two critical functions of antibodies, class switching and affinity maturation and may serve as a functional surrogate of protection. These functions were studied following systemic immunization of rhesus macaques with recombinant HLA constructs, linked with HIV and SIV antigens and HSP70 to dextran. The results showed significant upregulation of AID in CD20+ B cells, APOBEC 3G in CD27+ memory B cells and CD4+ effector memory T cells. After immunization the upregulated APOBEC 3G and AID were directly correlated in B cells (p<0.0001). Following challenge with SHIV SF162.P4 the viral load was inversely correlated with AID in B cells and APOBEC 3G in B and T cells, suggesting that both deaminases may have protective functions. Investigation of major interactions between DC, T cells and B cells showed significant increase in membrane associated IL-15 in DC and CD40L in CD4+ T cells. IL-15 binds the IL-15 receptor complex in CD4+ T and B cells, which may reactivate the DC, T and B cell interactions. The overall results are consistent with AID inhibiting pre-entry SHIV by eliciting IgG and IgA antibodies, whereas APOBEC 3G may contribute to the post-entry control of SHIV replication and cellular spread.
Collapse
Affiliation(s)
- Yufei Wang
- Mucosal Immunology Unit, King's College London, Guy's Hospital, London, United Kingdom
| | - Trevor Whittall
- Mucosal Immunology Unit, King's College London, Guy's Hospital, London, United Kingdom
| | - Durdana Rahman
- Mucosal Immunology Unit, King's College London, Guy's Hospital, London, United Kingdom
| | | | - Robert Vaughan
- Department of Tissue Typing, King's College London, Guy's Hospital, London, United Kingdom
| | | | - Lesley A. Bergmeier
- Queen Mary, University of London, Barts and The London Schools of Medicine and Dentistry, Centre for Clinical and Diagnostic Oral Sciences, London, United Kingdom
| | - David Montefiori
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, United States of America
| | | | | | - Thomas Lehner
- Mucosal Immunology Unit, King's College London, Guy's Hospital, London, United Kingdom
- * E-mail:
| |
Collapse
|
50
|
Influence of dendritic cells on B-cell responses during HIV infection. Clin Dev Immunol 2012; 2012:592187. [PMID: 22461837 PMCID: PMC3296217 DOI: 10.1155/2012/592187] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 12/11/2011] [Accepted: 12/12/2011] [Indexed: 12/23/2022]
Abstract
Dendritic cells (DCs) modulate B-cell differentiation, activation, and survival mainly through production of growth factors such as B lymphocyte stimulator (BLyS/BAFF). DC populations have been reported to be affected in number, phenotype and function during HIV infection and such alterations may contribute to the dysregulation of the B-cell compartment. Herein, we reflect on the potential impact of DC on the pathogenesis of HIV-related B cell disorders, and how DC status may modulate the outcome of mucosal B cell responses against HIV, which are pivotal to the control of disease. A concept that could be extrapolated to the overall outcome of HIV disease, whereby control versus progression may reside in the host's capacity to maintain DC homeostasis at mucosal sites, where DC populations present an inherent capacity of modulating the balance between tolerance and protection, and are amongst the earliest cell types to be exposed to the virus.
Collapse
|