Characterisation of vaginal <i>Lactobacillus</i> isolates from South African women towards the development of a biotherapeutic to optimise the vaginal microbiome

Abstract

HIV is a leading cause of morbidity and mortality in sub-Saharan Africa, where adolescent girls and young women are three times more likely to acquire HIV than their male counterparts. A key risk factor for HIV is bacterial vaginosis (BV), a condition characterised by the loss of beneficial <i>Lactobacillus</i> species and increased abundance of non-optimal, inflammatory bacteria. Although BV affects approximately 25% of women in sub-Saharan Africa, effective therapeutics are lacking. Live biotherapeutics containing optimal <i>Lactobacillus</i> spp. represent a promising strategy to improve BV treatment outcomes and reduce HIV infection risk. We isolated 181 vaginal <i>Lactobacillus</i> spp. from 25 BV-negative South African women and characterized 50 selected isolates. This led to the identification of live biotherapeutic candidates for African women with distinct genomes compared to isolates from other geographical regions. This study contributes to current knowledge of the characteristics that should be considered when screening novel isolates for this purpose.