title: Phenotypic Analysis of a Population of IgA+ Cells in the Follicle-Associated Epithelium of Mouse Peyer's Patches.
abstract: The follicle-associated epithelium (FAE) selectively transports prions, viruses, pathogenic bacteria, commensal microflora, and even secretory IgA (SIgA)-immune complexes from the intestinal lumen to underlying gut-associated lymphoid tissues like Peyer's patches. The FAE consists of a single layer of columnar epithelial cells that includes enterocytes and M (microfold) cells, intermingled with dendritic cells (DCs), macrophages, and naïve and memory B and T lymphocytes. In this report we describe a population of IgA+ cells that reside within and immediately below the FAE in mouse Peyer's patches. Immunofluorescence microscopy analysis indicated that the FAE-associated IgA+ cells were negative for surface antigen markers specific for B cells (B220), T cells (CD3), DCs (CD11c), and plasma cells (CD138). The IgA+ cells were also negative Ki-67 and IRF4, indicating that they are not mature B cells or plasma cells. The IgA+ cells were, however, often found in close proximity to DCs, leading us to speculate that the population of IgA+ cells in the FAE constitutes an atypical subset of B cells involved in mucosal antigen surveillance and/or immune recall.
authors.affiliation: Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, New York, 12208, United States of America.
authors.forename: Maria Olga
authors.initials: MO
authors.lastname: Hernandez
authors.affiliation: Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, New York, 12208, United States of America; Department of Biomedical Sciences, University at Albany, Albany, New York, 12208, United States of America.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Mantis
mesh_terms: D000818:Animals; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D002462:Cell Membrane / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology; D020895:Enterocytes / Q000166:cytology; D004847:Epithelial Cells / Q000166:cytology; D005260:Female; D007091:Image Processing, Computer-Assisted; D007070:Immunoglobulin A / Q000276:immunology*; D007075:Immunoglobulin M / Q000276:immunology; D007413:Intestinal Mucosa / Q000382:microbiology; D019394:Ki-67 Antigen / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D010581:Peyer's Patches / Q000276:immunology*; D010641:Phenotype; D013601:T-Lymphocytes / Q000166:cytology
chemical_list: D007070:Immunoglobulin A; D007075:Immunoglobulin M; D019394:Ki-67 Antigen