Figure 1
From: Microfold (M) cells: important immunosurveillance posts in the intestinal epithelium

The morphological features of M cells. (a) Cartoon illustrating the morphological features of M cells. Note the lack of microvilli and basolateral pocket containing a mononuclear phagocyte and a lymphocyte. (b) Whole-mount immunohistochemical analysis of glycoprotein 2 (GP2)+ mature M cells (green) in the follicle-associated epithelia (FAE) of a mouse Peyer’s patch. Note the regular distribution of the M cells across the FAE. Note also that in the steady-state M cells are restricted to the FAE and are mostly absent from the surrounding villi. Tissue counterstained to detect f-actin (blue). V, villi. (c) Scanning electron micrograph of the apical surface of a M-cell. Note characteristic lack of/blunted microvilli.