Morphological Study of Microfold Cells of Intestinal Lymphoid Follicles in Peyer’s Patches
A study was made of the morphology of microfold cells (M cells) of the human and rat Peyer's patch, and the morphological changes occurring due to aging and disease were examined. In the mature rat, the microfolds were classified into four types, and the microfolds were found to differ according to age. A microfold jutting out as a long, thin projection was noted in a patient with an intestinal infection. There was a close relationship between the enclosure of lymphoid cells by M cells and age in that with increasing age there were more M cells with enclosed lymphoid cells as well as more lymphoid cells within one M cell. It was also shown that pinocytosis as described by Fawcett occurs along with micropinocytosis in the incorporation of macromolecules.