Lactobacillus-Deficient Cervicovaginal Bacterial Communities Are Associated with Increased HIV Acquisition in Young South African Women

Immunity. 2017 Jan 17;46(1):29-37. doi: 10.1016/j.immuni.2016.12.013. Epub 2017 Jan 10.


Elevated inflammation in the female genital tract is associated with increased HIV risk. Cervicovaginal bacteria modulate genital inflammation; however, their role in HIV susceptibility has not been elucidated. In a prospective cohort of young, healthy South African women, we found that individuals with diverse genital bacterial communities dominated by anaerobes other than Gardnerella were at over 4-fold higher risk of acquiring HIV and had increased numbers of activated mucosal CD4+ T cells compared to those with Lactobacillus crispatus-dominant communities. We identified specific bacterial taxa linked with reduced (L. crispatus) or elevated (Prevotella, Sneathia, and other anaerobes) inflammation and HIV infection and found that high-risk bacteria increased numbers of activated genital CD4+ T cells in a murine model. Our results suggest that highly prevalent genital bacteria increase HIV risk by inducing mucosal HIV target cells. These findings might be leveraged to reduce HIV acquisition in women living in sub-Saharan Africa.

Keywords: HIV acquisition; HIV susceptibility; female genital tract (FGT); mucosal immunology; sub-Saharan Africa; vaginal microbiome.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Bacteria, Anaerobic
  • CD4-Positive T-Lymphocytes / immunology
  • Cervix Uteri / microbiology*
  • Cohort Studies
  • Female
  • Flow Cytometry
  • HIV Infections / microbiology*
  • Humans
  • Lactobacillus
  • Mice
  • Microbiota / immunology
  • Prevotella
  • South Africa
  • Vagina / microbiology*