Grant: Fellowship - PA: Biomedical / Clinical HIV/AIDS Research

The overall purpose of the proposed research is to define clinical relevance of a newly defined subgroup of Gardnerella vaginalis in relation to HIV infection and bacterial vaginosis (BV), a common but poorly understood vaginal condition associated with increased risk for HIV infection. Since G. vaginalis is commonly found in healthy women without vaginal symptoms, further work is required to define subgroups as specific risk factors for HIV infection and BV. Our previous work has defined 4 subgroups of G. vaginalis, with one subgroup ("B") found to be associated with BV diagnosis in African women. Many strains of this subgroup have been found to require oxygen-free conditions to grow, suggesting that they may have been overlooked in previous studies. Therefore, we propose to determine whether specific characteristics of Group B can explain the well-recognized but still ambiguous relationship between BV and HIV. Comparative genomics of 22 strains of G. vaginalis, including 2 newly sequenced Group B strains, will define genetic profile and expression of possible disease-causing factors. Group B and comparison strains will be grown with vaginal epithelial cells in order to determine if they express pathogenic factors, induce an inflammatory cytokine profile, or express HIV stimulatory factors. This research will elucidate the microbiological basis for an extremely common vaginal condition with high but poorly defined significance for reproductive health and HIV infection.