RESUMO
Several host factors have been implicated in resistance to HIV infection in individuals who remain HIV-seronegative despite exposure. In a cohort of HIV-serodiscordant heterosexual couples, we investigated interactions between systemic inflammation and T-cell activation in resistance to HIV infection. Males and females in stable long-term relationships with either HIV-infected or uninfected partners were recruited, blood T-cell activation (CD38, HLA-DR, CCR5 and Ki67) and plasma cytokine concentrations were evaluated. The HIV-negative exposed individuals had significantly lower frequencies of CCR5+ CD4+ and CD8+ T cells than unexposed individuals. Mean fluorescence intensity of CCR5 expression on CD4+ T cells was significantly lower in HIV-negative exposed than unexposed individuals. Protective CCR5 haplotypes (HHA/HHF*2, HHF*2/HHF*2, HHC/HHF*2, HHA/HHA, HHA/HHC and HHA/HHD) tended to be over-represented in exposed compared with unexposed individuals (38% versus 28%, P = 0·58) whereas deleterious genotypes (HHC/HHD, HHC/HHE, HHD/HHE, HHD/HHD and HHE/HHE) were under-represented (26% versus 44%; P = 0·16). Plasma concentrations of interleukin-2 (P = 0·02), interferon-γ (P = 0·05) and granulocyte-macrophage colony-stimulating factor (P = 0·006) were lower in exposed compared with unexposed individuals. Activation marker expression and systemic cytokine concentrations were not influenced by gender. We conclude that the dominant signature of resistance to HIV infection in this cohort of exposed but uninfected individuals was lower T-cell CCR5 expression and plasma cytokine concentrations.
Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Casamento , Receptores CCR5/metabolismo , Linfócitos T/imunologia , Adulto , Exposição Ambiental/efeitos adversos , Feminino , Regulação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Infecções por HIV/epidemiologia , Soropositividade para HIV , Haplótipos , Humanos , Interferon gama/sangue , Interleucina-2/sangue , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Receptores CCR5/genética , África do SulRESUMO
BACKGROUND: Persistent genital infections with high-risk HPV types increase risk of cervical disease and cancer. Since genital inflammation increases HIV acquisition risk and cancer progression, we evaluated whether HPV infection induces cytokine expression in the reproductive tract. METHODS: Genital cytokines concentrations were measured in 93 HIV-infected and 72 uninfected women. HPV typing was done by Roche Linear array. Persistence and clearance of HPV were evaluated using longitudinal data. RESULTS: Infection with HPV did not influence genital cytokine concentrations. In contrast, HIV-infected women had higher IL-1α, IL-6, IL-8, IP-10, MCP-1 and G-CSF concentrations compared to HIV-uninfected women, and HPV-infections that were more prevalent, persistent and multi-type. CONCLUSION: HPV did not influence inflammatory cytokine levels in the genital tract, although immune suppression may favor persistence.
Assuntos
Infecções por HIV/complicações , Infecções por Papillomavirus/complicações , Infecções do Sistema Genital/virologia , Adulto , Coinfecção , Citocinas/metabolismo , Feminino , Seguimentos , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Inflamação/virologia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Infecções do Sistema Genital/imunologiaRESUMO
BACKGROUND: Functional analysis of mononuclear leukocytes in the female genital mucosa is essential for understanding the immunologic effects of HIV vaccines and microbicides at the site of HIV exposure. However, the best female genital tract sampling technique is unclear. METHODS AND FINDINGS: We enrolled women from four sites in Africa and the US to compare three genital leukocyte sampling methods: cervicovaginal lavages (CVL), endocervical cytobrushes, and ectocervical biopsies. Absolute yields of mononuclear leukocyte subpopulations were determined by flow cytometric bead-based cell counting. Of the non-invasive sampling types, two combined sequential cytobrushes yielded significantly more viable mononuclear leukocytes than a CVL (p<0.0001). In a subsequent comparison, two cytobrushes yielded as many leukocytes (â¼ 10,000) as one biopsy, with macrophages/monocytes being more prominent in cytobrushes and T lymphocytes in biopsies. Sample yields were consistent between sites. In a subgroup analysis, we observed significant reproducibility between replicate same-day biopsies (r = 0.89, p = 0.0123). Visible red blood cells in cytobrushes increased leukocyte yields more than three-fold (p = 0.0078), but did not change their subpopulation profile, indicating that these leukocytes were still largely derived from the mucosa and not peripheral blood. We also confirmed that many CD4(+) T cells in the female genital tract express the α4ß7 integrin, an HIV envelope-binding mucosal homing receptor. CONCLUSIONS: CVL sampling recovered the lowest number of viable mononuclear leukocytes. Two cervical cytobrushes yielded comparable total numbers of viable leukocytes to one biopsy, but cytobrushes and biopsies were biased toward macrophages and T lymphocytes, respectively. Our study also established the feasibility of obtaining consistent flow cytometric analyses of isolated genital cells from four study sites in the US and Africa. These data represent an important step towards implementing mucosal cell sampling in international clinical trials of HIV prevention.
Assuntos
Leucócitos Mononucleares/patologia , Vagina/patologia , Adolescente , Adulto , Biópsia/métodos , Separação Celular , Sobrevivência Celular , Ensaios Clínicos como Assunto , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/prevenção & controle , Humanos , Reprodutibilidade dos Testes , Irrigação Terapêutica , Adulto JovemRESUMO
Cervical cytobrush sampling is a relatively non-invasive method for obtaining mucosal cells from the female genital tract. To define mucosal immune cells sampled by cervical cytobrushing and to validate this approach for local immunity studies, we investigated the impact of human immunodeficiency virus (HIV) status and inflammation on the yield and composition of cervical cytobrush specimens. Cervical cytobrush samples were obtained from 89 chronically HIV-infected and 46 HIV-negative women. The HIV-infected women had significantly higher yields of CD3(+), CD45(+), CD19(+), CD14(+), Langerin(+) and CD24(+) cells than the uninfected women. While cytobrush-derived T cells from uninfected women were predominantly CD4(+) (4.2 CD4 : 1 CD8), CD8(+) T cells were predominant in HIV-infected women (0.6 CD4 : 1 CD8). The majority of CD4(+) and CD8(+) T cells from HIV-infected and uninfected women were of the effector memory (CD45RA(-) CCR7(-) CD27(-)) phenotype. HIV-infected women had significantly elevated levels of interleukin (IL)-1beta, IL-6 and IL-8 in cervical supernatants compared with uninfected women. We observed a significant positive correlation between T-cell counts and IL-1beta, tumour necrosis factor (TNF)-alpha and IL-12 concentrations. Neutrophil counts correlated significantly with cervical concentrations of IL-1beta, TNF-alpha, IL-8, IL-6 and IL-10. Antigen-presenting cell numbers correlated significantly with TNF-alpha and IL-12 concentrations. HIV-infected women on antiretroviral therapy had similar levels of cervical lymphocyte infiltration and inflammation to women naïve to therapy. In conclusion, we suggest that inflammation at the cervix and HIV infection are likely to be key determinants in the absolute number of mucosal immune cells recovered by cervical cytobrushing.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Colo do Útero/imunologia , Infecções por HIV/imunologia , HIV-1 , Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/virologia , Colo do Útero/virologia , Doença Crônica , Citocinas/biossíntese , Citocinas/imunologia , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Inflamação/imunologia , Inflamação/virologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Mucosa/imunologia , Neutrófilos/imunologia , Neutrófilos/virologia , Carga Viral/imunologiaRESUMO
The female genital tract is the major route of heterosexual human immunodeficiency virus (HIV) acquisition and transmission. Here, we investigated whether HIV-specific CD8 T-cell-mediated immune responses could be detected in the genital mucosa of chronically HIV-infected women and whether these were associated with either local mucosal HIV shedding or local immune factors. We found that CD8(+) T-cell gamma interferon responses to Gag were detectable at the cervix of HIV-infected women but that the magnitude of genital responses did not correlate with those similarly detected in blood. This indicates that ex vivo HIV responses in one compartment may not be predictive of those in the other. We found that increased genital tumor necrosis factor alpha (TNF-alpha) and interleukin-10 (IL-10) levels correlated significantly with levels of Gag-specific CD8(+) T cells at the cervix. Women who were detectably shedding virus in the genital tract had significantly increased cervical levels of TNF-alpha, IL-1beta, IL-6, and IL-8 compared to women who were not detectably shedding virus. We were, however, unable to detect any association between the magnitude of cervical HIV-specific responses and mucosal HIV shedding. Our results support the hypothesis that proinflammatory cytokines in the female genital tract may promote HIV replication and shedding. In addition, we further show that inflammatory cytokines are associated with increased levels of HIV-specific CD8 effector cells at the genital mucosa but that these were not able to control genital HIV shedding.