Detection of HIV-1-specific CTL responses in Clade B infection with Clade C Peptides and not Clade B consensus peptides.
The variability of HIV-1 sequences within and between persons in vivo complicates immunologic screening with a fixed sequence, and using peptides based on consensus sequences therefore has become a common practice for pathogenesis and vaccine studies. Here, we screen a cohort of HIV-1-infected persons in the United States for CD8+ T lymphocyte (CTL) responses using Gag peptides based on the Clade C primary isolate DU422 and the consensus sequence for Clade B. Surprisingly, the DU422 and Clade B consensus peptides are similar in sensitivity, but many responses are detected only by one set or the other. About equal numbers of discordantly detected responses are specific to consensus Clade B peptides as DU422 peptides. A minority of discordant detection is due to the varying frames of the peptide sets and therefore a technical artifact; the majority is due to sequence differences. This lack of superiority of the Clade B consensus peptides to detect CD8+ T lymphocyte responses is an unexpected finding that suggests that detection of HIV-1-specific cellular immunity with these peptides may be significantly insensitive and raises questions as to whether screening with a single sequence adequately reflects responses to the viral swarm in vivo.
Sabado
Rachel Lubong
RL
Department of Medicine, Geffen School of Medicine, UCLA Medical Center, University of California, Los Angeles 90095, USA.
Kilpatrick
Stephanie
S
Ali
Ayub
A
Dagarag
Mirabelle
M
Ng
Hwee L
HL
Cao
Huyen
H
Yang
Otto O
OO
D000328:Adult; D000595:Amino Acid Sequence; D015331:Cohort Studies; D016384:Consensus Sequence; D005260:Female; D015683:Gene Products, gag / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010455:Peptides / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
D015683:Gene Products, gag; D016056:Immunodominant Epitopes; D010455:Peptides