HIV-1 MN Env 15-mer peptides better detect HIV-1 specific CD8 T cell responses compared with consensus subtypes B and M group 15-mer peptides.
OBJECTIVE
To compare the ability of three Env (15-mer) peptide sets derived from the HIV-1 MN, the subtype B consensus, and the group M consensus to detect HIV-1 specific interferon (IFN)-gamma responses in HIV-1 subtype B infected subjects.


METHODS
Peripheral blood mononuclear cells were obtained from 17 HIV-1 subtype B seropositive and 5 HIV-1 seronegative subjects. Peptide matrices comprising each peptide set were used in IFN-gamma Elispot assays to screen for T cell epitopes. Following matrix deconvolution, individual peptides were analyzed by IFN-gamma intracellular cytokine-staining to confirm and characterize the responding cells.


RESULTS
HIV specific IFN-gamma responses were detected in 17 of 17 HIV-1 seropositive and none of 5 HIV-1 seronegative subjects by Elispot. Within the 17 HIV-1 seropositives, 16, 14, and 11 subjects responded to MN, B consensus, and group M env peptides, respectively. Responses were confirmed by intracellular cytokine analysis in 14 subjects and were in the CD3CD8 compartment. Cross-recognition of 'equivalent' peptides (i.e., peptides mapping to the same sequence region from the three peptide sets) was observed in 9 of 17 subjects. Peptide set specific responses to individual peptides were also observed; 11, 1, and 1 subjects demonstrated peptide set specific responses to MN, B consensus, and consensus group M, respectively.


CONCLUSIONS
MN derived Env peptides were better able to detect HIV-1 specific CD8 T cell responses, many of which were not detectable by the equivalent clade or group consensus peptides. No single peptide set detected all the IFN-gamma responses within an individual. These results demonstrate the importance of reagent selection for monitoring of HIV responses in HIV-1 infected individuals and subsequently vaccine recipients.
Rutebemberwa
Alleluiah
A
Henry M. Jackson Foundation and the US Military HIV Research Program, Rockville, Maryland 20850, USA. arutebemberwa@hivresearch.org
Currier
Jeffrey R
JR
Jagodzinski
Linda
L
McCutchan
Francine
F
Birx
Deborah
D
Marovich
Mary
M
Cox
Josephine H
JH
D000328:Adult; D018791:CD4 Lymphocyte Count; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D016384:Consensus Sequence / Q000235:genetics / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015686:Gene Products, env / Q000378:metabolism*; D015658:HIV Infections / Q000235:genetics / Q000276:immunology*; D015497:HIV-1 / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007111:Immunity, Cellular / Q000235:genetics / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D019562:Viral Load
D015686:Gene Products, env; D007371:Interferon-gamma