Bacterial vaginosis is a common reproductive infection in which commensal vaginal lactobacilli
are displaced by a mixed population of pathogenic bacteria. Bacterial vaginosis increases susceptibility
to HIV, and it has been suggested that host innate immune responses to pathogenic bacteria
contribute to enhanced infection, yet the cellular mechanisms mediating the increased HIV susceptibility
We evaluated the HIV-enhancing effects of bacterial vaginosis by inoculating endocervical epithelia with Atopobium
vaginae, a bacterial vaginosis-associated bacteria, and assaying secreted factors for HIV-enhancing activity. When epithelia
and A. vaginae were cocultured, we observed increased HIV-enhancing activity mediated by secreted low molecular
weight factors. From this complex mixture we identified several upregulated host proteins, which functioned in combination
to enhance HIV infection.
These studies suggest that the host immune response to bacterial vaginosis-associated bacteria results in the release of
HIV-enhancing factors. The combined activity of bacterial vaginosis-induced proteins likely mediates HIV enhancement.