New Approach for M-Cell-Specific Molecules Screening by Comprehensive Transcriptome Analysis
1 Supramolecular Biology, International Graduate School of Arts and Sciences, Yokohama City University, Kanagawa 230-0045, Japan
2 Laboratory for Epithelial Immunobiology, Research Center for Allergy and Immunology, RIKEN, Kanagawa 230-0045, Japan
3 Research Institute for Biological Sciences, Tokyo University of Science, Noda, Chiba 278-0022, Japan
4 Department of Pathology and Laboratory Medicine, Emory Vaccine Center, School of Medicine, Emory University, Atlanta, GA 30322, USA
Received 2 June 2009 ; accepted 2 July 2009.
A minor population of M cells within the follicle-associated epithelium (FAE) of intestinal Peyer's patches (PPs) serves as a major portal for entry of exogenous antigens. Characterization of the mammalian M cells, including identification of M-cell surface molecules used for bacterial uptake, has been hampered by their relative rarity. In contrast, M cells constitute virtually all of the FAE cells in the avian bursa of Fabricius. We therefore performed comparative gene expression profiling of chicken and murine FAE to identify commonly expressed genes by M cells in both species. The comprehensive transcriptome analysis revealed that 28 genes were commonly up-regulated in FAE from both species. In situ hybridization revealed that annexin A10 (Anxa10) mRNA was scattered in FAE, and co-localized with Ulex europaeus agglutinin-1 binding to M cells. Whole-mount immunostaining also revealed that cellular prion protein (PrPC) was expressed on the luminal side of the apical plasma membrane of M cells, and co-localized with grycoprotein 2 that recognizes only M cells in murine PP. Our findings identify new M-cell-specific molecules through using comprehensive transcriptome analysis. These conserved molecules in M cells of mice and chickens may play essential roles in M-cell function and/or differentiation.
Key words: M cell; the bursa of Fabricius; annexin A10; cellular prion protein
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