10 Sep Vaginal microbiome and proteome

Disturbance in the microorganism environment of the vagina (‘dysbiosis’) is associated with increased HIV acquisition. However, the mechanisms remain largely unknown.

To investigate the association between the vaginal microbiome and the mucosal immune response, we compared cervicovaginal human proteins of 50 Rwandan female sex workers who had different cervicovaginal microbiome (VMB) compositions. These were, in order of increasing bacterial diversity: Lactobacillus crispatus-dominated VMB, Lactobacillus iners-dominated VMB, moderate dysbiosis, and severe dysbiosis. We compared relative protein abundances among these four VMB groups using two approaches: targeted (abundance of pre-defined mucosal barrier proteins) and untargeted (differentially abundant proteins among all human proteins identified). As bacterial diversity increased, we found mucus alterations, cytoskeleton alterations, increasing lactate dehydrogenase A/B as markers of cell death, increasing proteolytic activity, altered antimicrobial peptide balance, increasing proinflammatory cytokines, and decreasing immunoglobulins. Although temporal relationships cannot be derived, our findings support the hypothesis that dysbiosis causes cervicovaginal inflammation and other detrimental changes to the mucosal barrier.

Please click here for the article.