title: Persistent high frequency of human immunodeficiency virus-specific cytotoxic T cells in peripheral blood of infected donors.
abstract: Human immunodeficiency virus (HIV)-specific cytotoxic T lymphocytes (CTLs) are thought to play a major role in the immune response to HIV infection. The HIV-specific CTL response is much stronger than previously documented in an infectious disease, yet estimates of CTL frequency derived from limiting-dilution analysis (LDA) are relatively low and comparable to other viral infections. Here we show that individual CTL clones specific for peptides from HIV gag and pol gene products are present at high levels in the peripheral blood of three infected patients and that individual CTL clones may represent between 0.2% and 1% of T cells. Previous LDA in one donor had shown a frequency of CTL precursors of 1/8000, suggesting that LDA may underestimate CTL effector frequency. In some donors individual CTL clones persisted in vivo for at least 5 years. In contrast, in one patient there was a switch in CTL usage suggesting that different populations of CTLs can be recruited during infection. These data imply strong stimulation of CTLs, potentially leading some clones to exhaustion.
authors.affiliation: Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, United Kingdom.
authors.forename: P A
authors.initials: PA
authors.lastname: Moss
authors.forename: S L
authors.initials: SL
authors.lastname: Rowland-Jones
authors.forename: P M
authors.initials: PM
authors.lastname: Frodsham
authors.forename: S
authors.initials: S
authors.lastname: McAdam
authors.forename: P
authors.initials: P
authors.lastname: Giangrande
authors.forename: A J
authors.initials: AJ
authors.lastname: McMichael
authors.forename: J I
authors.initials: JI
authors.lastname: Bell
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002999:Clone Cells; D017931:DNA Primers; D015683:Gene Products, gag / Q000096:biosynthesis / Q000235:genetics; D015684:Gene Products, pol / Q000096:biosynthesis / Q000235:genetics; D015750:Genes, gag; D015751:Genes, pol; D006678:HIV / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D015658:HIV Infections / Q000276:immunology* / Q000635:transmission / Q000821:virology; D006467:Hemophilia A / Q000150:complications; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D017260:Receptor-CD3 Complex, Antigen, T-Cell / Q000096:biosynthesis / Q000235:genetics; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis / Q000235:genetics; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000821:virology*; D014158:Transcription, Genetic
chemical_list: D017931:DNA Primers; D015683:Gene Products, gag; D015684:Gene Products, pol; D017260:Receptor-CD3 Complex, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta