Biology subjects

Frempong, J. F.

Publications and source records attributed to Frempong, J. F..

2 recordsLinked to original sources

bioRxiv2025

Microbiota-derived indole metabolites inhibit rotavirus infection in vitro and in vivo and in human infants

Rotavirus (RV) is the leading cause of life-threatening gastroenteritis in children under five despite effective RV vaccines availability, necessitating novel protective strategies for high-risk populations. Gut microbiota can modulate RV susceptibility and vaccine immunogenicity, yet underlying mechanisms are poorly characterized. Here, we demonstrate that microbiota-derived indole metabolites confer protection against RV infection. In healthy adults, higher fecal indole-3-acetic acid (IAA) and indole-3-propionic acid (IPA) levels associated with reduced fecal RV shedding following challenge. In human intestinal enteroids (HIEs), IAA pre-treatment inhibited human RV Wa G1P[8] replication via the aryl hydrocarbon receptor (AhR) pathway. In mice, treatment with AhR agonist indole-3-carbinol (I3C) significantly reduced fecal shedding of murine RV strain EDIM-Cambridge. Finally, Zambian infants with active RV infection exhibited lower fecal IAA and IPA levels than age-matched healthy controls. These findings demonstrate that microbiota-derived AhR ligands consistently inhibit RV infection across three experimental models and hold promise for protecting at-risk pediatric populations.

microbiology↗

bioRxiv2021

Cysteine dependence in Lactobacillus iners constitutes a novel therapeutic target to modify the vaginal microbiota

Vaginal microbiota composition affects several important reproductive health outcomes. Lactobacillus crispatus-dominant bacterial communities have favorable associations whereas anaerobe-dominant communities deficient of lactobacilli are linked to poor outcomes, including bacterial vaginosis (BV). Lactobacillus iners, the most abundant vaginal species worldwide, has adverse associations compared to L. crispatus, but standard metronidazole treatment for BV promotes L. iners-dominance, likely contributing to post-treatment relapse. L. iners is under-studied because it fails to grow in standard Lactobacillus media in vitro. Here we trace this in vitro phenotype to a species-specific cysteine requirement associated with limitations in cysteine-related transport mechanisms and show that vaginal cysteine concentrations correlate with Lactobacillus abundance in vivo. We demonstrate that cystine uptake inhibitors selectively impede L. iners growth and that combining an inhibitor with metronidazole thus promotes L. crispatus dominance of defined BV-like communities. These findings identify a novel target for therapeutic vaginal microbiota modulation to improve reproductive health.

microbiology↗