[Immunodominance in CD8+ T cell responses to HIV-1 synthesized epitopes].
OBJECTIVE
To investigate immunodominance in CD8+ T cell responses to human immunodeficiency virus type 1 (HIV-1) epitopes.


METHODS
Frequency of Interferon-gamma (IFN-gamma) secreting cells and the proliferation percentage of CD8+ T cells in PBMC from an HIV-1-infected long term nonprogressor (LTNP) were assessed after stimulation with either the 34 pools of 701 overlapping peptides covering the regions of HIV-1 Env, Pol, Gag, Vif, Nef, Tat or some single peptides, by using various assays including enzyme-linked immunospot (ELISPOT) and CFSE Carboxy-fluorescein diacetate, succinimidyl ester (CFSE) labeling and flow cytometry.


RESULTS
HIV-1 Gag peptides induced the highest frequency of IFN-gamma secreting cells, followed by Nef, Tat, and Vif. Meanwhile, Env and Pol failed to induce significant responses. In the IFN-gamma ELISPOT assay, stimulation with single peptide and the corresponsive peptide pool generated analogous results. In addition, the frequencies of IFN-gamma secreting cells and the proliferation percentage of CD8+ T cells detected-ELISPOT and CFSE labeling and flow cytometry were proportional, when single peptides were used for stimulation.


CONCLUSIONS
CD8+ T cells can respond to some specific HIV-1 epitopes and induce immunodominant responses. As a complimentary approach to the standard of ELISPOT assay, We recommend a novel CFSE labeling and flow cytometry assay for the examination of immunodominance in studies of HIV-1 specific proliferation percentage of CD8+ T cell responses.
Tang
Yang-Bo
YB
Institute of infectious diseases, Guangzhou Eighth People's Hospital, Guangzhou, China. yangbotang@tom.com
Tang
Xiao-Ping
XP
Jin
Xia
X
D000328:Adult; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D015658:HIV Infections / Q000276:immunology* / Q000821:virology; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology* / Q000494:pharmacology; D007371:Interferon-gamma / Q000378:metabolism
D016056:Immunodominant Epitopes; D007371:Interferon-gamma