25-hydroxycholesterol restricts human norovirus replication in human intestinal enteroids

We explored the antiviral potential of 25-hydroxycholesterol (25-HC), a key regulator of cholesterol homeostasis, different human norovirus genotypes on different jejunal human intestinal enteroid (HIE) cell lines. The results provide novel insights into host-pathogen interactions and the modulation of innate immune responses in the gastrointestinal environment. We found several key findings from our study. Pretreatment of HIEs with 25-HC significantly inhibited human norovirus replication in a dose-dependent manner. 25-HC treatment upregulated innate immune response pathways while concurrently downregulating genes involved in cholesterol biosynthesis. Reduced expression of PCSK9, which plays a crucial role in cholesterol metabolism and ACAT2, which catalyzes the conversion of free cholesterol into cholesteryl esters, was observed in 25-HC-treated HIEs. 25-HC treatment also stimulated the production of immune mediators, including CCL2, CCL20, and IL-23, suggesting broader immunomodulatory effects. Collectively, our findings support a potential therapeutic role for 25-HC in limiting norovirus infection and provide a foundation for further exploration of cholesterol derivatives in antiviral strategies.