title: B cell lines from a subset of patients with common variable immunodeficiency undergo enhanced apoptosis associated with an increased display of CD95 (Apo-1/fas), diminished CD38 expression, and decreased IgG and IgA production.
abstract: Investigation of common variable immunodeficiency (CVI) is hampered by lack of a suitable in vitro models. We have developed EBV-transformed B lymphoblastoid cell lines from a selected subset of CVI patients and characterized them for phenotypic and functional properties that provide evidence for their representation of the CVI disease state. B cell lines from the patients expressed increased levels of sIgM and reduced levels of sIgD and sIgG. Essentially none of the CVI-derived B cell lines produced IgG and IgA while all produced IgM, in contrast to normal B cell lines that produced large amounts of IgG and IgM and detectable levels of IgA. Expression of CD95 (fas/Apo-1), a molecule that can induce apoptosis, was increased on the CVI B cell lines while CD38, a novel signaling molecule whose stimulation may prevent apoptosis, showed reduced expression. The B cell lines from the CVI patients exhibit increased apoptosis in vitro spontaneously, in response to anti-CD95 mAb and to X-irradiation. These phenotypic and functional changes are similar to findings on freshly derived B cells from the patients. EBV-derived B cell lines from patients with hyper-IgM immunodeficiency and X-linked agammaglobulinemia did not demonstrate increased CD95 expression or enhanced apoptosis. Thus the EBV-derived B cell lines from our selected CVI patients manifest many characteristics of the patients' fresh cells and may provide critical reagents for the further elucidation of the nature of the B cell dysfunction in the selected subset of CVI patients.
authors.affiliation: Hart and Louise Lyon Laboratory, Division of Clinical Immunology and Allergy, University of California Los Angeles School of Medicine 90024-1680, USA.
authors.forename: B C
authors.initials: BC
authors.lastname: Guo
authors.forename: A
authors.initials: A
authors.lastname: Saxon
mesh_terms: D036541:ADP-ribosyl Cyclase; D051997:ADP-ribosyl Cyclase 1; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000378:metabolism*; D017209:Apoptosis / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D016923:Cell Death / Q000276:immunology; D002461:Cell Line, Transformed; D017074:Common Variable Immunodeficiency / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000096:biosynthesis*; D007074:Immunoglobulin G / Q000096:biosynthesis*; D008562:Membrane Glycoproteins; D009699:N-Glycosyl Hydrolases / Q000378:metabolism*; D010641:Phenotype; D011947:Receptors, Antigen, B-Cell / Q000378:metabolism; D019014:fas Receptor / Q000378:metabolism*
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D008562:Membrane Glycoproteins; D011947:Receptors, Antigen, B-Cell; D019014:fas Receptor; D009699:N-Glycosyl Hydrolases; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D051997:ADP-ribosyl Cyclase 1