HPV and microbiota dynamics in the vaginal environment
Human papillomaviruses (HPVs) are among the most oncogenic infectious agents known to humans. They are responsible for nearly all cervical cancers and a large fraction of other anogenital or oropharyngeal cancers. HPVs are also among the most prevalent sexually transmitted infections (STIs). Fortunately, more than 90% of HPV infections in young adults are cleared within three years. Yet, despite their prevalence, we know little about their dynamics.
I will present ongoing work stemming from the PAPCLEAR clinical study, which we implemented in Montpellier (France) to tackle this question and followed 149 young women for a median duration of 290 days. Every two months, we measured HPV viral loads, immune cell counts, and cytokines in the cervical region, along with circulating anti-HPV antibody titers. By analysing these longitudinal data with Bayesian hierarchical statistical models, we obtained the first picture of HPV infection kinetics and the associated immune response.
In the same cohort, we followed the composition of the vaginal microbiota using metabarcoding methods targeting the 16S RNA. This dataset is one of the largest in Europe but represents one of the densest longitudinal follow-ups to date. Using Markov Chain modelling, we analysed how the various community state types vary over time along with covariates associated with community shifts. Furthermore, using a community ecology model, we found that resource availability in the vaginal environment could explain transitions between optimal and non-optimal vaginal microbiota compositions.
Given the impact of the vaginal microbiota on susceptibility to STIs, fertility, and general well-being, this improved understanding of the vaginal ecosystem can have direct implications for women’s health.
