Fig. 3
From: M cell-dependent antigen uptake on follicle-associated epithelium for mucosal immune surveillance
Antigen uptake receptors on the apical surface of M cells. GP2 binds to the HA1 domain of the botulinum toxin and FimH+ type 1 pili of certain bacterial species. PrPC facilitates internalization of Brucella abortus into M cells. Umod serves as an uptake receptor for Lactobacillus acidophilus. β1-integrin is activated by Aif1 to function as an uptake receptor for Yersinia spp. Antigens taken up by M cells are transcytosed to an M cell pocket, whereby antigen-presenting cells, like dendritic cells, capture the antigens