Life Science Paradigm Challenge

There’s a specific gut bug that’s way more common in women, and it might be the reason they get MS more often.

March 20, 2026

Original Paper

Female-enriched Eggerthella lenta drives neuroinflammation and IFN-γ via host receptor TLR2

bioRxiv · 10.64898/2026.03.16.711194

The Takeaway

Researchers identified that Eggerthella lenta, which is enriched in the female gut, triggers neuroinflammation by activating a specific immune receptor. This provides a direct causal link between the microbiome and the well-known sex bias in autoimmune diseases.

From the abstract

Women are at increased risk of autoimmune diseases, including multiple sclerosis (MS); however, the degree to which sex differences in the gut microbiota impact autoimmunity remains largely unexplored. Our 27-cohort meta-analysis revealed 60 sex-associated gut bacterial species. Leveraging an independent clinical cohort, we demonstrate that female-enriched species significantly associate with MS status and clinical disability (EDSS). Top female-enriched species Eggerthella lenta drove disease in