Abstract

Intestinal microfold (M) cells are critical for sampling antigens in the gut and initiating the intestinal mucosal immune response. In this study, we found that the oral administration of dextran sulfate sodium (DSS) andSalmonellainfection induced colitis. In the process, the expression levels of M cell differentiation-related genes were synchronized with the kinetics of pro-inflammatory cytokines. Compared to wild-type (WT) mice,MyD88−/−mice exhibited significantly lower expression levels of M cell differentiation-related genes. However, DSS induced colitis inMyD88−/−mice but failed to promote the transcription of M cell differentiation related genes. Furthermore, the receptor activator of the Nuclear Factor-κB ligand (RANKL) upregulated the transcription of M cell differentiation related genes in murine intestinal organoids prepared from both WT andMyD88−/−mice. Meanwhile, fewer changes in M cell differentiation related genes were found inMyD88−/−mice as compared to WT mice. Hence, we concluded that myeloid differentiation factor 88 (MyD88) is an essential molecule for colitis- and RANKL-related differentiation of M cells.Keywords:colonic M cells;MyD88;colitis;DSS