Impact of human immunodeficiency virus 1 infection and inflammation on the composition and yield of cervical mononuclear cells in the female genital tract.

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.

Impact of mucosal inflammation on cervical human immunodeficiency virus (HIV-1)-specific CD8 T-cell responses in the female genital tract during chronic HIV infection.

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.