Protective effects of human breast milk-derived exosomes on inflammatory bowel disease through modulation of immune cells
Ki‐Uk Kim, Jisu Kim, Hyunjun Jang, Kang Bin Dan, Bo Kyeong Kim, Yong Woo Ji, Dae Yong Yi, Hyeyoung Min
Abstract
Human breast milk (HBM)-derived exosomes play a crucial role not only in infant nutrition but also in modulating inflammation, immunity, and epithelial cell protection. This study investigated how HBM-derived exosomes regulate immune cell development and function. The exosomes promoted the differentiation of naïve CD4 + T cells into Treg and Th2 cells while suppressing their differentiation into Th17 and Th1 cells. They also enhanced the proliferation of intestinal epithelial Caco-2 cells and reduced apoptosis in dextran sulfate sodium (DSS)-damaged caco-2 cells. In a DSS-induced colitis mouse model, the exosomes significantly alleviated disease severity, as evidenced by improvements in colon length, disease activity index, and histology grades. Furthermore, the exosomes normalized CD4 + T cell subsets in the spleen, mesenteric lymph nodes, and colon, restoring levels comparable to controls. These findings suggest that HBM-derived exosomes hold promise as a potential therapeutic strategy for inflammatory bowel disease by modulating T-cell responses and protecting intestinal epithelial cells.