Bacterial microbiome and host inflammatory gene expression in foreskin tissue

Area of Science:

• Microbiology
• Immunology
• Genomics

Background:

• The penile epithelial microbiome's role in health and disease is largely unknown.
• Understanding the penile microbiome is crucial for male reproductive health.

Purpose of the Study:

• To investigate the penile foreskin microbiome composition in adolescent males.
• To determine if short-term antiretroviral drug use alters the penile microbiome.
• To explore the relationship between the penile microbiome and host inflammatory gene expression.

Main Methods:

• RNA sequencing and 16S rRNA gene sequencing were performed on foreskin tissue from 144 adolescent males in South Africa and Uganda.
• Participants received placebo or short-course antiretroviral drugs (emtricitabine + tenofovir disoproxil fumarate or emtricitabine + tenofovir alafenamide).
• Bacterial populations and gene expression related to innate immunity and inflammation were analyzed.

Main Results:

• A diverse anaerobic penile microbiome was identified, with *Corynebacterium acnes* more prevalent in South African participants.
• No significant differences in bacterial populations were observed between placebo and antiretroviral drug recipients.
• Bacterial taxa abundance showed a negative correlation with inflammatory and innate immune gene expression.

Conclusions:

• Short-course antiretroviral use did not impact the penile tissue microbiome.
• The penile microbiome appears to be inversely associated with inflammatory responses, suggesting a commensal role.
• Further research is needed to elucidate the complex interactions between the penile microbiome and host immunity.