title: Early detection of antibodies against rDNA-produced HIV proteins with a flow cytometric assay.
abstract: There is evidence that some human immunodeficiency virus (HIV)-infected individuals have prolonged periods of seronegativity. A flow cytometric immunoreactive bead (IRB) assay is described for quantitative, simultaneous, and early detection of antibodies to HIV. Polystyrene beads of four diameters, each size coated with a different HIV recombinant DNA-produced protein (p24, p31, gp41, or gp120), bound anti-HIV antibodies detected with fluorescent antiglobulin. The IRB assay was performed on a panel of blood donor samples, many giving consistently false-positive enzyme immunoassay (EIA) and indeterminant Western blot (WB) results. The IRB assay proved as sensitive and more specific than currently licensed EIA and WB tests. Results on serial samples from eight HIV-infected individuals indicated that quantitation of anti-p24 by IRB assay may be useful in monitoring disease progression. Sequential pre- and post-EIA seroconversion sera from 35 HIV-infected homosexual men were tested by the IRB assay using IgM- and IgG-specific fluorescent probes. All 35 cases were IRB assay positive for at least one rDNA-p either before (17 of 35, 49%) or at the time of EIA positivity. Eleven cases (31%) initially had only IgM anti-HIV, primarily to gp41 (17%). In two individuals, the IgM response was detected at least 18 months before EIA seroconversion. The IRB assay is a widely applicable analytic procedure, potentially useful in pretransfusion anti-HIV screening of blood.
authors.affiliation: Department of Laboratory Medicine, School of Medicine, University of California, San Francisco 94143.
authors.forename: J J
authors.initials: JJ
authors.lastname: Scillian
authors.forename: T M
authors.initials: TM
authors.lastname: McHugh
authors.forename: M P
authors.initials: MP
authors.lastname: Busch
authors.forename: M
authors.initials: M
authors.lastname: Tam
authors.forename: M J
authors.initials: MJ
authors.lastname: Fulwyler
authors.forename: D Y
authors.initials: DY
authors.lastname: Chien
authors.forename: G N
authors.initials: GN
authors.lastname: Vyas
mesh_terms: D005434:Flow Cytometry / Q000379:methods / Q000592:standards; D015483:HIV Antibodies / Q000032:analysis* / Q000096:biosynthesis; D015488:HIV Antigens / Q000276:immunology; D016655:HIV Core Protein p24; D015699:HIV Envelope Protein gp120; D015700:HIV Envelope Protein gp41; D006679:HIV Seropositivity / Q000097:blood* / Q000175:diagnosis; D015497:HIV-1 / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007124:Immunoenzyme Techniques / Q000592:standards; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D008863:Microspheres; D011994:Recombinant Proteins / Q000276:immunology*; D012191:Retroviridae Proteins / Q000276:immunology*; D014759:Viral Envelope Proteins / Q000276:immunology
chemical_list: D015483:HIV Antibodies; D015488:HIV Antigens; D016655:HIV Core Protein p24; D015699:HIV Envelope Protein gp120; D015700:HIV Envelope Protein gp41; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011994:Recombinant Proteins; D012191:Retroviridae Proteins; D014759:Viral Envelope Proteins