title: Longitudinal analysis of HIV-1-specific antibody responses.
abstract: Laboratory assays for determining recent HIV-1 infection are of great public health importance for aiding in the estimation of HIV incidence. Concerns have been raised about the potential for misclassification with serology-based assays due to fluctuations in the antibody response, particularly following progression to AIDS. We characterized longitudinal antibody responses to HIV using a cohort of men who have sex with men (MSM) sampled for up to 17 years, in which 57% of the 65 study subjects included in the current analyses progressed to AIDS during the study period. Envelope-specific total IgG antibody levels, avidity, and p24-specific IgG3 levels were evaluated using a multiplexed Bio-Plex assay. For the majority of the analytes, no significant difference in IgG reactivity was observed between AIDS and non-AIDS specimens. Although a slight decline in gp120 reactivity was noted with decreasing CD4(+) T cell count, the drop in assay values was relatively minimal and would likely not lead to an increase in the misclassification rate of the assay. A peak in HIV-1 p24 IgG3 levels was observed during early infection, as confirmed by testing 1,216 specimens from 342 recent seroconverters with the Bio-Plex assay. As expected, IgG3 reactivity declined with disease progression and decreasing CD4(+) T cell count in the MSM cohort; however, 37% of the study subjects exhibited relatively high IgG3 levels late in the course of infection.
authors.affiliation: Laboratory Branch, Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention , Atlanta, Georgia .
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Curtis
authors.forename: M Susan
authors.initials: MS
authors.lastname: Kennedy
authors.forename: S Michele
authors.initials: SM
authors.lastname: Owen
mesh_terms: D000915:Antibody Affinity; D000917:Antibody Formation; D015331:Cohort Studies; D015483:HIV Antibodies / Q000097:blood*; D016655:HIV Core Protein p24 / Q000276:immunology; D015658:HIV Infections / Q000276:immunology* / Q000821:virology; D015497:HIV-1 / Q000276:immunology*; D018451:Homosexuality, Male; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008137:Longitudinal Studies; D008297:Male; D011446:Prospective Studies; D013997:Time Factors; D054299:env Gene Products, Human Immunodeficiency Virus / Q000276:immunology
chemical_list: D015483:HIV Antibodies; D016655:HIV Core Protein p24; D007074:Immunoglobulin G; D054299:env Gene Products, Human Immunodeficiency Virus