title: A novel human B cell subpopulation representing the initial germinal center population to express AID.
abstract: We have identified a novel mature human B-cell subpopulation in the human tonsil that has characteristics of both naive B cells and germinal center B cells including the expression of activation-induced cytidine deaminase (AID), which is essential for the process of immunoglobulin somatic hypermutation and class-switch recombination. These cells are clearly somatically hypermutated, albeit modestly. Their phenotype (IgD(+)CD38(-)CD23(-)FSC(hi)CD71(+)) is unique and suggests they may be intermediate between both naive and germinal center cells. Morphologically they are also distinct from other B-cell subpopulations. The evidence presented suggests these cells may be the founder cells of the germinal center reaction (a pro-GC cell) and may be the normal counterpart of the mantle cell lymphoma cell.
authors.affiliation: Program in Molecular Immunogenetics, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA.
authors.forename: Grant R
authors.initials: GR
authors.lastname: Kolar
authors.forename: Darshna
authors.initials: D
authors.lastname: Mehta
authors.forename: Rosana
authors.initials: R
authors.lastname: Pelayo
authors.forename: J Donald
authors.initials: JD
authors.lastname: Capra
mesh_terms: D051997:ADP-ribosyl Cyclase 1 / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology* / Q000201:enzymology*; D015415:Biomarkers; D048430:Cell Shape; D018920:Coculture Techniques; D003564:Cytidine Deaminase / Q000378:metabolism*; D018858:Germinal Center / Q000166:cytology* / Q000201:enzymology*; D006801:Humans; D007072:Immunoglobulin D / Q000276:immunology; D018655:Lymphocyte Count; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D017455:Receptors, IgE / Q000276:immunology; D014158:Transcription, Genetic / Q000235:genetics; D000098830:AICDA (Activation-Induced Cytidine Deaminase)
chemical_list: D015415:Biomarkers; D007072:Immunoglobulin D; D017455:Receptors, IgE; D051997:ADP-ribosyl Cyclase 1; D000098830:AICDA (Activation-Induced Cytidine Deaminase); D003564:Cytidine Deaminase