title: Long latency precedes overt seroconversion in sexually transmitted human-immunodeficiency-virus infection.
abstract: Signs of latent HIV infection were sought in stored serum samples collected before overt seroconversion, confirmed by enzyme-linked immunosorbent assay (ELISA), from 9 subjects with human-immunodeficiency-virus (HIV) infection, in serum from 25 seronegative sexual partners of HIV-seropositive men and from 23 other seronegative, homosexually active men. Free HIV antigen and/or low-titre antibodies to recombinant structural (core, env) or non-structural (3' orf, sor, tat) proteins were seen 6-14 months before seroconversion in all 9 subjects who seroconverted. Antibodies against core proteins detected by western blot were usually the first sign of latent HIV infection. 5 of the 25 ELISA-negative exposed partners have shown HIV antigenaemia and antibodies against core proteins for 16-34 months. By in-situ hybridisation, HIV-specific RNA was detected in peripheral-blood non-lymphoid mononuclear cells in some of the latently infected partners. All subjects with latent HIV infection had normal numbers of T4 lymphocytes but half of them lost their in-vitro proliferative T-cell response to a recall antigen (purified protein derivative of tuberculin). Early HIV infection, characterised by a low-level and restricted antibody response towards HIV core and regulatory proteins, seems mainly to affect antigen-presenting cells.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000175:diagnosis / Q000276:immunology / Q000635:transmission*; D000914:Antibodies, Viral / Q000032:analysis*; D000956:Antigens, Viral / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D006678:HIV / Q000276:immunology*; D015483:HIV Antibodies; D015488:HIV Antigens; D006716:Homosexuality; D006801:Humans; D008297:Male; D012367:RNA, Viral / Q000032:analysis; D011994:Recombinant Proteins / Q000276:immunology; D012189:Retrospective Studies; D012725:Sexual Behavior; D013997:Time Factors; D014758:Viral Core Proteins / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D015483:HIV Antibodies; D015488:HIV Antigens; D012367:RNA, Viral; D011994:Recombinant Proteins; D014758:Viral Core Proteins