AUTHOR=Pyles Richard B. , Miller Aaron L. , Maxwell Carrie , Dawson Lauren , Richardson-Harman Nicola , Swartz Glenn , O'Neill Cynthia , Walker Cattlena , Milligan Gregg N. , Madsen Timothy , Motamedi Massoud , Vargas Gracie , Vincent Kathleen L. 

TITLE=Characterization of the Ovine Vaginal Microbiome and Inflammation Patterns as an Improved Testing Model of Human Vaginal Irritation

JOURNAL=Frontiers in Reproductive Health

VOLUME=Volume 3 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/reproductive-health/articles/10.3389/frph.2021.714829

DOI=10.3389/frph.2021.714829

ISSN=2673-3153

ABSTRACT=Development of therapies targeted to improve women’s health have utilized direct vaginal delivery as a more effective and less toxic method of protection from HIV and other pathogens. Vaginal applicants and delivery devices that provide sustained effects have met with increasing acceptability, but efficacy and toxicity outcomes have not been successfully predicted by preclinical in vitro studies and animal modeling. We have explored the utilization of sheep as a model for testing the safety of vaginal applicants and devices based on spatial and structural similarities to the human vagina. As recently noted by the FDA, an additional safety measure is the impact on the vaginal microbiome (VMB) that is known to contribute to vaginal health and influence pathogen susceptibility and drug metabolism. To advance the utility of the sheep vaginal model, we completed a thorough molecular characterization of the ovine VMB utilizing both next generation sequencing (NGS) and PCR methods. The process also created a custom PCR array to quantify ovine VMB community profiles in affordable, higher throughput fashion. The results from vaginal swabs (>475 samples) collected from nonpregnant crossbred Dorset and Merino ewes treated with selected vaginal applicants or collected as sham samples established 16 community types (VMB CTs). To associate VMB CTs with eubiosis or dysbiosis, we also completed custom ELISAs for 6 cytokines identifying IL1B, IL8, TNFa and CXCL10 as useful markers to support characterization of ovine vaginal inflammation. The results indicated Pasteurella, Actinobacillus, Pseudomonas, Bacteroides, Leptotrichia and E. coli were common markers of eubiosis (low inflammatory marker expression) while Haemophilus, Ureaplasma and Corynebacterium associated with dysbiosis (high cytokine levels). Utilizing the optimized work flow we also confirmed the utility of three commonly used vaginal applicants for impact on the VMB and inflammatory state producing a dataset that supports the recommendation for the use of sheep for testing of vaginal applicants and devices as part of preclinical pipelines.