RESUMO
Human immunodeficiency virus (HIV) infectivity increases as receptor/coreceptor expression levels increase. We determined peripheral CD4, CCR5, and CXCR4 expression levels in HIV-uninfected women who used depot medroxyprogesterone acetate (DMPA; n = 32), the levonorgestrel-releasing intrauterine device (LNG-IUD; n = 27), oral contraceptive pills (n = 32), or no hormonal contraception (n = 33). The use of LNG-IUD increased the proportion of CD4(+) and CD8(+) T cells that expressed CCR5; increases in the magnitude of T-cell subset CCR5 expression were observed with DMPA and LNG-IUD use (P < .01 for all comparisons). LNG-IUD and, to a lesser extent, DMPA use were associated with increased peripheral T-cell CCR5 expression.
Assuntos
Anticoncepcionais Orais Combinados/administração & dosagem , Levanogestrel/administração & dosagem , Acetato de Medroxiprogesterona/administração & dosagem , Receptores CCR5/metabolismo , Adulto , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Anticoncepção , Escolaridade , Feminino , Soronegatividade para HIV , Humanos , Receptores CCR5/genética , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Subpopulações de Linfócitos T/metabolismoRESUMO
BACKGROUND: The long-term impact of allogeneic hematopoietic stem cell transplantation (HSCT) on human immunodeficiency virus type 1 (HIV-1) reservoirs in patients receiving combination antiretroviral therapy (cART) is largely unknown. METHODS: We studied the effects of a reduced-intensity conditioning allogeneic HSCT from donors with wild-type-CCR5(+) cells on HIV-1 peripheral blood reservoirs in 2 patients heterozygous for the ccr5Δ32 mutation. In-depth analyses of the HIV-1 reservoir size in peripheral blood, coreceptor use, and specific antibody responses were performed on samples obtained before and up to 3.5 years after HSCT receipt. RESULTS: Although HIV-1 DNA was readily detected in peripheral blood mononuclear cells (PBMCs) before and 2-3 months after HSCT receipt, HIV-1 DNA and RNA were undetectable in PBMCs, CD4(+) T cells, or plasma up to 21 and 42 months after HSCT. The loss of detectable HIV-1 correlated temporally with full donor chimerism, development of graft-versus-host disease, and decreases in HIV-specific antibody levels. CONCLUSIONS: The ability of donor cells to engraft without evidence of ongoing HIV-1 infection suggests that HIV-1 replication may be fully suppressed during cART and does not contribute to maintenance of viral reservoirs in peripheral blood in our patients. HSCTs with wild-type-CCR5(+) donor cells can lead to a sustained reduction in the size of the peripheral reservoir of HIV-1.
Assuntos
Infecções por HIV/virologia , HIV-1/isolamento & purificação , Transplante de Células-Tronco , Transplante Homólogo , Carga Viral , Antirretrovirais/administração & dosagem , Terapia Antirretroviral de Alta Atividade/métodos , Deleção de Genes , Infecções por HIV/tratamento farmacológico , HIV-1/patogenicidade , Heterozigoto , Humanos , Masculino , Receptores CCR5/genética , Receptores CCR5/metabolismo , Receptores de HIV/genética , Receptores de HIV/metabolismoRESUMO
Acute HIV infection is marked by dramatic viral replication associated with preferential replication within secondary lymphoid tissues, such as lymph nodes (LNs), that is rapidly but incompletely contained to a viral setpoint. Accumulating evidence supports a role for natural killer (NK) cells in the early control of HIV infection; however, little is known about the location of their antiviral control. Given that HIV replicates profusely in LNs during early infection, we sought to define whether changes occurred in the NK cell infiltrate within these sites during the first year of HIV infection. Surprisingly, NK cell numbers and distribution were unaltered during early HIV infection. LN NK cells expressed decreased inhibitory receptors, were more highly activated, and expressed elevated TRAIL, potentially conferring a superior capacity for NK cells to become activated and control infection. Most noticeably, KIR(+) NK cells were rarely detected in the LN during HIV infection, associated with diminished migratory capacity in the setting of reduced expression of CX3CR1 and CXCR1. Thus, incomplete control of HIV viral replication during early disease may be due to the inefficient recruitment of KIR(+) NK cells to this vulnerable site, providing HIV a niche where it can replicate unabated by early NK-cell-mediated innate pressure.
Assuntos
Infecções por HIV/imunologia , HIV/fisiologia , Evasão da Resposta Imune , Células Matadoras Naturais/metabolismo , Adulto , Idoso , Receptor 1 de Quimiocina CX3C , Movimento Celular/imunologia , Células Cultivadas , Regulação da Expressão Gênica/imunologia , HIV/patogenicidade , Infecções por HIV/virologia , Humanos , Imunidade Inata , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Células Matadoras Naturais/virologia , Linfonodos/patologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/metabolismo , Receptores de Interleucina-8A/genética , Receptores de Interleucina-8A/metabolismo , Receptores KIR/genética , Receptores KIR/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Replicação ViralRESUMO
BACKGROUND: Worldwide, approximately 90% of all human immunodeficiency virus (HIV) transmissions occur mucosally; almost all involve R5 strains. Risks of sexual HIV acquisition are highest for rectal, then vaginal, and finally oral exposures. METHODS: Mucosal lacerations may affect the rank order of susceptibility to HIV but cannot be assessed in humans. We measured relative virus transmissibility across intact mucosae in macaques using a single stock of SHIV-1157ipd3N4, a simian-human immunodeficiency virus encoding a primary R5 HIV clade C env (SHIV-C). RESULTS: The penetrability of rhesus macaque mucosae differed significantly, with rectal challenge requiring the least virus, followed by vaginal and then oral routes (P = .031, oral vs vaginal; P < .001 rectal vs vaginal). These findings imply that intrinsic mucosal properties are responsible for the differential mucosal permeability. The latter paralleled the rank order reported for humans, with relative risk estimates within the range of epidemiological human studies. To test whether inflammation facilitates virus transmission--as predicted from human studies--we established a macaque model of localized buccal inflammation. Systemic infection occurred across inflamed but not normal buccal mucosa. CONCLUSION: Our primate data recapitulate virus transmission risks observed in humans, thus establishing R5 SHIV-1157ipd3N4 in macaques as a robust model system to study cofactors involved in human mucosal HIV transmission and its prevention.
Assuntos
HIV-1/patogenicidade , Mucosa/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Vírus da Imunodeficiência Símia/patogenicidade , Animais , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos , Progressão da Doença , Suscetibilidade a Doenças/virologia , Feminino , Infecções por HIV/transmissão , Humanos , Inflamação/virologia , Mucosa Intestinal/virologia , Macaca mulatta/virologia , Mucosa Bucal/virologia , Reto/virologia , Vagina/virologia , Carga ViralRESUMO
OBJECTIVE: To define the impact of chronic viremia and associated immune activation on B-cell exhaustion in HIV infection. DESIGN: Progressive HIV infection is marked by B-cell anergy and exhaustion coupled with dramatic hypergammaglobulinemia. Although both upregulation of CD95 and loss of CD21 have been used as markers of infection-associated B-cell dysfunction, little is known regarding the specific profiles of dysfunctional B cells and whether persistent viral replication and its associated immune activation play a central role in driving B-cell dysfunction. METHODS: Multiparameter flow cytometry was used to define the profile of dysfunctional B cells. The changes in the expression of CD21 and CD95 were tracked on B-cell subpopulations in patients with differential control of viral replication. RESULTS: : Although the emergence of exhausted, CD21 tissue-like memory B cells followed similar patterns in both progressors and controllers, the frequency of CD21 activated memory B cells was lower in spontaneous controllers. CONCLUSION: Our results suggest that the loss of CD21 and the upregulation of CD95 occur as separate events during the development of B-cell dysfunction. The loss of CD21 is a marker of B-cell exhaustion induced in the absence of appreciable viral replication, whereas the upregulation of CD95 is tightly linked to persistent viral replication and its associated immune activation. Thus, these dysfunctional profiles potentially represent two functionally distinct states within the B-cell compartment.
Assuntos
Linfócitos B/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Receptores de Complemento 3d/imunologia , Viremia/imunologia , Replicação Viral/imunologia , Receptor fas/imunologia , Adulto , Fator Ativador de Células B/imunologia , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-IdadeRESUMO
In addition to neutralization, antibodies mediate other antiviral activities including antibody-dependent cellular phagocytosis (ADCP), antibody-dependent cellular cytotoxicity (ADCC), as well as complement deposition. While it is established that progressive HIV infection is associated with reduced ADCC and ADCP, the underlying mechanism for this loss of function is unknown. Here we report considerable changes in FcR expression over the course of HIV infection on both mDCs and monocytes, including elevated FcγRI expression in acute HIV infection and reduced expression of FcγRII and FcγRIIIa in chronic HIV infection. Furthermore, selective blockade of FcγRII alone was associated with a loss in ADCP activity, suggesting that FcγRII plays a central role in modulating ADCP. Overall, HIV infection is associated with a number of changes in FcR expression on phagocytic cells that are associated with changes in their ability to respond to antibody-opsonized targets, potentially contributing to a failure in viral clearance in progressive HIV-1 infection.
Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Imunidade Humoral , Imunidade Inata , Fagócitos/imunologia , Receptores Fc/genética , Receptores Fc/imunologia , Citotoxicidade Celular Dependente de Anticorpos , Doença Crônica , Feminino , Expressão Gênica , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Masculino , FagocitoseRESUMO
Listeria monocytogenes (Lm) is known to induce strong cellular immune responses. We constructed a live-attenuated Lm vector, Lmdd-BdopSIVgag, which encodes SIVmac239 gag. Intragastric (i.g.) administration of 3 × 10(12) bacteria to rhesus macaques was safe and induced anti-Gag cellular but no humoral immune responses. Boosting of Gag-specific cellular responses was observed after i.g. administration of Lmdd-BdopSIVgag to previously vaccinated RM despite preexisting anti-Lm immunity shown by lymphoproliferative responses. Surprisingly, anti-Lm cellular responses were also detected in non-vaccinated controls, which may reflect the fact that Lm is a ubiquitous bacterium. The novel, live-attenuated Lmdd-BdopSIVgag may be an attractive platform for oral vaccine delivery.
Assuntos
Portadores de Fármacos , Produtos do Gene gag/imunologia , Vetores Genéticos , Listeria monocytogenes/genética , Vacinas contra a SAIDS/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Produtos do Gene gag/genética , Imunidade Celular , Imunização Secundária/métodos , Macaca mulatta , Vacinas contra a SAIDS/administração & dosagem , Vacinas contra a SAIDS/genética , Vírus da Imunodeficiência Símia/genética , Vacinação/métodos , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologiaRESUMO
Phagocytosis can be induced via the engagement of Fcγ receptors by antibody-opsonized material. Furthermore, the efficiency of antibody-induced effector functions has been shown to be dramatically modulated by changes in antibody glycosylation. Because infection can modulate antibody glycans, which in turn modulate antibody functions, assays capable of determining the induction of effector functions rather than neutralization or titer provide a valuable opportunity to more fully characterize the quality of the adaptive immune response. Here we describe a robust and high-throughput flow cytometric assay to define the phagocytic activity of antigen-specific antibodies from clinical samples. This assay employs a monocytic cell line that expresses numerous Fc receptors: including inhibitory and activating, and high and low affinity receptors--allowing complex phenotypes to be studied. We demonstrate the adaptability of this high-throughput, flow-based assay to measure antigen-specific antibody-mediated phagocytosis against an array of viruses, including influenza, HIV, and dengue. The phagocytosis assay format further allows for simultaneous analysis of cytokine release, as well as determination of the role of specific Fcγ-receptor subtypes, making it a highly useful system for parsing differences in the ability of clinical and vaccine induced antibody samples to recruit this critical effector function.
Assuntos
Citometria de Fluxo/métodos , Imunoensaio/métodos , Fagocitose , Anticorpos/química , Anticorpos/imunologia , Anticorpos Bloqueadores/imunologia , Especificidade de Anticorpos , Linhagem Celular , Citocinas/biossíntese , Glicosilação , Infecções por HIV/imunologia , Humanos , Imunidade Inata , Imunoglobulina G/química , Imunoglobulina G/imunologia , Técnicas In Vitro , Influenza Humana/imunologia , Microscopia Confocal , Microscopia de Vídeo , Monócitos/imunologia , Receptores de IgG/imunologia , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Vacinas/imunologiaRESUMO
We sought to induce primate immunodeficiency virus-specific cellular and neutralizing antibody (nAb) responses in rhesus macaques (RM) through a bimodal vaccine approach. RM were immunized intragastrically (i.g.) with the live-attenuated Listeria monocytogenes (Lm) vector Lmdd-BdopSIVgag encoding SIVmac239 gag. SIV Gag-specific cellular responses were boosted by intranasal and intratracheal administration of replication-competent adenovirus (Ad5hr-SIVgag) encoding the same gag. To broaden antiviral immunity, the RM were immunized with multimeric HIV clade C (HIV-C) gp160 and HIV Tat. SIV Gag-specific cellular immune responses and HIV-1 nAb developed in some RM. The animals were challenged intrarectally with five low doses of R5 SHIV-1157ipEL-p, encoding a heterologous HIV-C Env (22.1% divergent to the Env immunogen). All five controls became viremic. One out of ten vaccinees was completely protected and another had low peak viremia. Sera from the completely and partially protected RM neutralized the challenge virus > 90%; these RM also had strong SIV Gag-specific proliferation of CD8⺠T cells. Peak and area under the curve of plasma viremia (during acute phase) among vaccinees was lower than for controls, but did not attain significance. The completely protected RM showed persistently low numbers of the α4ß7-expressing CD4⺠T cells; the latter have been implicated as preferential virus targets in vivo. Thus, vaccine-induced immune responses and relatively lower numbers of potential target cells were associated with protection.
Assuntos
Adenoviridae/imunologia , Produtos do Gene gag/imunologia , Proteína gp160 do Envelope de HIV/imunologia , Listeria monocytogenes/imunologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/imunologia , Adenoviridae/genética , Animais , Anticorpos Neutralizantes/sangue , Antígenos Virais/genética , Antígenos Virais/imunologia , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , ELISPOT , Produtos do Gene gag/administração & dosagem , Proteína gp160 do Envelope de HIV/administração & dosagem , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Imunidade nas Mucosas , Imunização Secundária , Interferon gama/análise , Listeria monocytogenes/genética , Macaca mulatta/imunologia , Macaca mulatta/virologia , Vírus da Imunodeficiência Símia/imunologia , Vacinação , Carga Viral , Viremia/imunologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/administração & dosagemRESUMO
Primary effusion lymphomas (PELs) are invariably infected by human herpesvirus type 8 (HHV8) and often co-infected by Epstein-Barr virus (EBV). We found that expression of major histocompatibility complex class I (MHC-I) surface molecules was significantly decreased in PEL cells when compared with HHV8 negative lymphomas, irrespective of EBV infection. MHC-I downregulation rendered PEL cells sensitive to recognition and killing by natural killer (NK) cells. Intriguingly, analysis of MHC-I non-restricted cytotoxicity in two PEL patients indicated a reduced NK cell activity when compared with healthy individuals. These data suggest that PEL outgrowth may require an impaired NK cell function.