Clostridium butyricum is a probiotic bacterium with emerging scientific evidence suggesting its relevance in supporting the immune system, specifically the gut-associated lymphoid tissue (GALT), which includes Peyer's patches. Peyer's patches are lymphoid follicles in the small intestine that play a crucial role in mucosal immunity by monitoring intestinal bacteria and generating immune responses. Several preclinical studies, mostly in animal models, indicate that administration of C. butyricum can influence the function and development of Peyer's patches. For example, research has demonstrated that C. butyricum can increase IgA production, a key antibody type produced by B cells in Peyer's patches, and can modulate the balance of immune cells in the gut mucosa (Fukuda et al., 2011; Li et al., 2018). The mechanisms appear to involve the production of butyrate, a short-chain fatty acid that supports intestinal barrier function and modulates immune responses.

While these findings are promising, most evidence comes from animal studies or in vitro experiments, with limited direct clinical evidence in humans specifically targeting Peyer's patches. However, the role of C. butyricum in enhancing mucosal immunity and modifying gut microbiota composition provides a plausible rationale for its use in supporting this aspect of the immune system. Thus, there is a scientific basis for its use, but more human research is needed to establish strong clinical recommendations.