Peyer’s Patches of SCID Mice After Syngeneic Normal Bone Marrow Transplantation

Abstract

The gut-associated lymphoid tissue (GALT), which is present in all vertebrates as ileal Peyer’s patches, consists of tightly packed follicles that are separated by small T cell areas and contain 95% surface IgM-positive B cells (Reynaud et al. 1991). Antigens and microorganisms in the intestinal lumen are separated from the lymphoid cells of Peyer’s patches by follicle-associated epithelium (FAE) containing M cells (reviewed by Neutra et al. 1996a). M cells are clearly different from neighbouring enterocytes and goblet cells and are specialized for transepithelial transport of antigens and microorganisms (Giannasca and Neutra 1994). The apical membranes of M cells contain glycoconjugates that may mediate the binding of lectins and lectin-like microbial surface proteins (Gebert and Hach 1993). Recent lectin binding studies have identified fucosylated glycoconjugates unique to the apical surfaces and cytoplasmic contents of mouse M cells (Clark et al. 1993; Falk et al. 1994).