title: Isotypes and IgG subclasses of anti-Fab antibodies in human immunodeficiency virus-infected hemophilia patients.
abstract: We reported recently that anti-Fab autoantibodies of the IgG isotype are associated with the decrease of helper/inducer (CD4+) lymphocytes in human immunodeficiency virus-infected (HIV+) hemophilia patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC). In the present study we investigated the subclass distribution of IgG-anti-Fab autoantibodies, and whether anti-Fab antibodies of the IgA and IgM isotypes also are associated with the development of AIDS. Sera of HIV+ patients with AIDS had significantly higher IgA-anti-Fab activity than HIV+ patients with ARC (p < 0.02), HIV+ patients without AIDS/ARC (p < 0.0001), HIV-negative (HIV-) patients (p < 0.001), or healthy controls (p < 0.0001). An inverse association was found between IgA-anti-Fab activity and CD4+ cell counts (r = -0.396, p < 10(-6)). In contrast, no association of CD4+ cell counts was observed with IgM-anti-Fab. However, IgM-anti-Fab was significantly increased in patients with thrombocytopenia. We found a significant association between IgA-anti-Fab activity and serum neopterin concentrations (r = 0.310, p < 10(-5)). IgG-anti-Fab activity was detected mainly in the IgG3 fraction, although in HIV+ patients with AIDS/ARC various IgG subclasses were present. Affinity-purified anti-Fab antibodies isolated from sera of AIDS patients bound to rgp120-preincubated CD4+ cells of a healthy individual, supporting our hypothesis that anti-Fab antibodies and free circulating gp120 molecules are involved in the elimination of uninfected CD4+ cells. Removal of anti-Fab autoantibodies from the circulation by immune adsorbance might be a useful approach in the treatment of AIDS.
authors.affiliation: Department of Transplantation Immunology, University of Heidelberg, FRG.
authors.forename: C
authors.initials: C
authors.lastname: Süsal
authors.forename: H H
authors.initials: HH
authors.lastname: Oberg
authors.forename: V
authors.initials: V
authors.lastname: Daniel
authors.forename: C
authors.initials: C
authors.lastname: Dörr
authors.forename: P
authors.initials: P
authors.lastname: Terness
authors.forename: A
authors.initials: A
authors.lastname: Huth-Kühne
authors.forename: R
authors.initials: R
authors.lastname: Zimmermann
authors.forename: G
authors.initials: G
authors.lastname: Opelz
mesh_terms: D000386:AIDS-Related Complex / Q000097:blood / Q000150:complications / Q000276:immunology; D000163:Acquired Immunodeficiency Syndrome / Q000097:blood / Q000150:complications / Q000276:immunology; D000888:Antibodies, Anti-Idiotypic / Q000097:blood* / Q000276:immunology; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002846:Chromatography, Affinity; D015658:HIV Infections / Q000097:blood / Q000150:complications* / Q000276:immunology; D006467:Hemophilia A / Q000097:blood / Q000150:complications* / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood / Q000276:immunology; D007140:Immunoglobulin Fab Fragments / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood* / Q000145:classification; D007132:Immunoglobulin Isotypes / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood / Q000276:immunology; D007958:Leukocyte Count; D013921:Thrombocytopenia / Q000097:blood / Q000150:complications / Q000276:immunology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D001323:Autoantibodies; D007070:Immunoglobulin A; D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G; D007132:Immunoglobulin Isotypes; D007075:Immunoglobulin M