Lectin binding defines and differentiates M-cells in mouse small intestine and caecum

M-cell surface glycoconjugate expression was investigated by applying a panel of lectins to whole fixed mouse Peyer's and caecal patches. While the majority of lectins failed to identify mouse M-cells, the lectin Euonymus europaeus differentially stained the surface of M-cells in both mouse Peyer's and caecal patches, and the lectins Ulex europaeus II and Bandeiraea simplicifolia I isolectin B4 identified M-cells in the Peyer's and caecal patch follicle associated epithelium, respectively. These three mouse M-cell markers failed to identify rat and rabbit Peyer's patch M-cells, although both Euonymus europaeus and Ulex europaeus II differentially stained M-cells in the periphery of rabbit caecal patch domes. These site and species related variations in M-cell surface glycoconjugate expression may reflect the local microorganism populations and will have important implications if orally delivered vaccines and drugs are to be targeted to M-cells via their surface glycoconjugates.