title: Human immunodeficiency virus type 1 (HIV-1) infection a median of 18 months before a diagnostic western blot. Evidence from a cohort of homosexual men.
abstract: OBJECTIVE
  To study the natural history of human immunodeficiency virus type 1 (HIV-1) infection, we used an in-vitro amplification technique to detect HIV-1 nucleic acid sequences in sequential aliquots of peripheral blood mononuclear cells from homosexual men enrolled in the Multicenter AIDS Cohort Study.
  
  
  METHODS
  Blinded, longitudinal study of 24 homosexual men who were positive for HIV-1 antibodies at a recent follow-up visit.
  
  
  RESULTS
  Coded clinical samples were evaluated using two enzyme-linked immunosorbent assays (whole virus and gp120-gp41 fragment), Western blot, a p24 antigen capture assay, virus cocultivation, and in-vitro amplification of conserved regions from the HIV-1 gag and env open-reading frames. In 20 of the 24 men an HIV-1 enzymatically amplified product was detected before HIV-1 antibody seroconversion: at 42 months before seroconversion in two cases; at 36 months in one case; at 30 months in one case; at 24 months in four cases; at 18 months in eight cases; at 12 months in one case; and at 6 months in three cases (median, 18 months). In the four other men, detection of an HIV-1 enzymatically amplified product was concurrent with confirmation of antibody seroconversion by Western blot.
  
  
  CONCLUSIONS
  There is a long and variable interval between virus acquisition and a diagnostic serum antibody response, perhaps due to the prolonged, persistent infection characteristic of the lentiviruses (family Retroviridae).
authors.affiliation: Northwestern University Medical School, Chicago, Illinois.
authors.forename: S M
authors.initials: SM
authors.lastname: Wolinsky
authors.forename: C R
authors.initials: CR
authors.lastname: Rinaldo
authors.forename: S
authors.initials: S
authors.lastname: Kwok
authors.forename: J J
authors.initials: JJ
authors.lastname: Sninsky
authors.forename: P
authors.initials: P
authors.lastname: Gupta
authors.forename: D
authors.initials: D
authors.lastname: Imagawa
authors.forename: H
authors.initials: H
authors.lastname: Farzadegan
authors.forename: L P
authors.initials: LP
authors.lastname: Jacobson
authors.forename: K S
authors.initials: KS
authors.lastname: Grovit
authors.forename: M H
authors.initials: MH
authors.lastname: Lee
mesh_terms: D015492:AIDS Serodiagnosis; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D005784:Gene Amplification; D015683:Gene Products, gag / Q000032:analysis; D015488:HIV Antigens / Q000032:analysis; D016655:HIV Core Protein p24; D015658:HIV Infections / Q000175:diagnosis*; D015497:HIV-1 / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D006716:Homosexuality; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011533:Proviruses / Q000235:genetics / Q000302:isolation & purification; D013601:T-Lymphocytes; D013997:Time Factors; D014758:Viral Core Proteins / Q000032:analysis; D014776:Virus Cultivation
chemical_list: D015683:Gene Products, gag; D015488:HIV Antigens; D016655:HIV Core Protein p24; D014758:Viral Core Proteins