Human immunodeficiency virus (HIV) Tat-reactive antibodies present in normal HIV-negative sera and depleted in HIV-positive sera. Identification of the epitope.
We have detected, in sera of normal human immunodeficiency virus (HIV)-free subjects, IgM antibodies reactive with the Tat protein of HIV in significant titers and at very high frequency, and, in HIV-positive sera, progressively lower titers as HIV pathogenesis ensues. Epitope analysis indicates that the Tat-reactive antibodies of both HIV-negative and HIV-positive sera are homologous, suggesting, therefore, that their decline in HIV-positive sera may represent attrition of a host defense factor. The identified epitope displays minimal homology with that previously defined for another set of IgM antibodies shown to be present in normal sera, deficient in HIV-positive sera, and postulated to be natural antibodies. We propose that the Tat-reactive antibodies, as well, are a set of natural antibodies and that the normal humoral immune system includes a repertoire of antibodies, nonimmunogenic in origin, that contribute to immune homeostasis and, consequently, to host resistance to HIV pathogenesis.
Rodman
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TC
Laboratory of Cell Biology, Rockefeller University, New York, New York 10021.
Pruslin
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FH
To
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Winston
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R
D000595:Amino Acid Sequence; D000918:Antibody Specificity / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology*; D005260:Female; D015696:Gene Products, tat / Q000276:immunology*; D015483:HIV Antibodies / Q000097:blood*; D015488:HIV Antigens / Q000276:immunology; D006679:HIV Seropositivity / Q000097:blood / Q000276:immunology*; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D054322:tat Gene Products, Human Immunodeficiency Virus
D000939:Epitopes; D015696:Gene Products, tat; D015483:HIV Antibodies; D015488:HIV Antigens; D007075:Immunoglobulin M; D054322:tat Gene Products, Human Immunodeficiency Virus