Project description:<p>Preterm birth is the leading cause of neonatal morbidity and mortality. A failure to predict and understand the causes of preterm birth have limited effective interventions and therapeutics. From a cohort of 2,000 pregnant women, we performed a nested case control study on 107 well-phenotyped cases of spontaneous preterm birth (sPTB) and 432 women delivering at term. Modern and innovative Bayesian modeling of vaginal microbiota identified features of these communities associated with PTB. Seven bacterial taxa were shown to have relative abundances significantly associated with an increased risk of sPTB, with a stronger effect in African American women. However, higher vaginal levels of β-defensins significantly decreased the risk of sPTB associated with the vaginal microbiota in an ethnicity-dependent manner. These findings hold promise for the development of novel diagnostics that could more accurately identify women at risk for sPTB early in pregnancy and offer new therapeutic strategies that would include immune modulators and microbiome-based therapeutics to reduce this significant health burden.</p>
Project description:A lactobacilli dominated microbiota in most pre and post-menopausal women is an indicator of vaginal health. A Nugent scoring system serves as a proxy for determining the ratio of lactobacilli to other vaginal inhabitants where a high score usually represents a diseased state, whilst an intermediate score represents a warning zone. The objective of this double blinded, placebo-controlled crossover study was to evaluate in 14 post-menopausal women with an intermediate score, the effect of vaginal administration of probiotic L. rhamnosus GR-1 and L. reuteri RC-14 on the microbiota and host response. The probiotic treatment did not result in changes to clinical parameters such as dryness, irritation and comfort, compared to when placebo was applied. Analysis using 16S rRNA sequencing and metabolomics profiling revealed that the proportional abundance of Lactobacillus was increased following probiotic administration as compared to placebo, which was weakly associated with an increase in lactate levels. Analysis of host responses by microarray showed the probiotics had an immune-modulatory response and multiplex cytokine analysis showed up-regulation of IL-5. This is the first study to use an interactomic approach for the study of vaginal probiotic administration in post-menopausal women. It shows that in some cases multifaceted approaches are required to detect the subtle trigger molecular changes induced by the host to instillation of probiotic strains. A total of 35 total RNA samples extracted from vaginal brushes were analyzed on Affymetrix Gene 2.0 ST arrays from 14 Participants collected over multiple visits including administration of either a probiotic supplement or placebo control.
