Generation of Immunoglobulin diversity in human gut-associated lymphoid tissue.
The organised gut associated lymphoid tissue (GALT) exists adjacent to an extensive and diverse luminal flora. The follicle associated epithelium and associated dendritic cells and lymphocytes form a tightly fortified gateway between the flora and the host that permits connectivity between them and chronic activation of the lymphoid compartment. As a consequence, plasma cell precursors are generated continuously, and in abundance, in GALT by clonal proliferation. Clonal proliferation alone on this scale would reduce the spectrum of B cell specificity. To compensate, GALT also houses molecular machinery that diversifies the receptor repertoire by somatic hypermutation, class switch recombination and receptor revision. These three processes of enhancing the diversity of mature B cells ensure that although clonally related plasma cells may secrete immunoglobulin side by side in the mucosa they rarely have identical antigen binding sites.
Spencer
Jo
J
Peter Gorer Department of Immunobiology, King's College London, Guy's Hospital Campus, St Thomas' St, London SE1 9RT, United Kingdom.
Barone
Francesca
F
Dunn-Walters
Deborah
D
D000818:Animals; D000916:Antibody Diversity; D000942:Antigens, Bacterial / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D001419:Bacteria / Q000276:immunology; D002454:Cell Differentiation; D049109:Cell Proliferation; D003713:Dendritic Cells / Q000276:immunology; D006801:Humans; D018928:Immunity, Mucosal; D007071:Immunoglobulin A, Secretory / Q000276:immunology / Q000378:metabolism; D017578:Immunoglobulin Class Switching; D007147:Immunoglobulin Light Chains / Q000235:genetics; D007422:Intestines / Q000254:growth & development / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D008221:Lymphoid Tissue / Q000254:growth & development / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D027041:Somatic Hypermutation, Immunoglobulin
D000942:Antigens, Bacterial; D007071:Immunoglobulin A, Secretory; D007147:Immunoglobulin Light Chains