title: Neutralization of HTLV-III/LAV replication by antiserum to thymosin alpha 1.
abstract: An antiserum prepared against thymosin alpha 1, a hormone secreted by the thymus gland, effectively neutralized the AIDS-associated virus [HTLV-III/LAV (clone BH-10)] and blocked its replication in H9 cells. Reverse transcriptase activity and expression of the HTLV-III/LAV antigens p15 and p24 were inhibited by purified immunoglobulin G preparations of antisera to thymosin alpha 1. The antiviral activity of the antiserum was found to be due to a region of homology between thymosin alpha 1 and p17, a product of the gag gene of HTLV-III/LAV. Comparison of the primary sequences of thymosin alpha 1 and the gag protein revealed a 44% to 50% homology in an 18-amino acid region, between positions 11 and 28 on thymosin alpha 1 and 92 and 109 on the gag protein. The effectiveness of the thymosin alpha 1 antiserum and of immunoglobulin G-enriched preparations in blocking replication of HTLV-III(BH-10) in H9 cells suggests a novel approach to the development of an AIDS vaccine. A vaccine directed against the gag protein might overcome the problem of genetic drift in the envelope region of the virus and be useful against all genetic variants of HTLV-III/LAV.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000382:microbiology; D000328:Adult; D000818:Animals; D002648:Child; D017977:Deltaretrovirus / Q000187:drug effects* / Q000502:physiology; D015683:Gene Products, gag; D006801:Humans; D007106:Immune Sera / Q000276:immunology / Q000494:pharmacology*; D007074:Immunoglobulin G / Q000276:immunology; D011817:Rabbits / Q000276:immunology; D012191:Retroviridae Proteins / Q000276:immunology; D000077596:Thymalfasin; D013947:Thymosin / Q000031:analogs & derivatives* / Q000276:immunology; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D015683:Gene Products, gag; D007106:Immune Sera; D007074:Immunoglobulin G; D012191:Retroviridae Proteins; D013947:Thymosin; D000077596:Thymalfasin