Analysis of Nef-specific interferon-γ secretion responses in HIV-1 B/C recombinant virus infectors

Abstract

Objective To analyze characteristics of Nef-specific T lymphocyte responses in Chinese HIV-1 recombinant subtype B/C infectors. Methods 19 HIV-1 recombinant subtype B/C infectors infected within 1 year, 40 chronic infectors infected for more than 3 years were enrolled in this cohort study. Elispot assay was used to observe HIV-1 specific T lymphocyte responses in HIV-1 recombinant subtype B/C infectors. Results Nef-specific T lymphocyte responses of interferon-gamma secretion were identified in 15 Chinese HIV-1 recombinant subtype B/C infectors infected within 1 year. The specific T lymphocytes were mainly targeted at four peptides which span from Nef 83 to 135: EVA7081.1, EVAT081.5, EVA7081.6 and EVAT081.48. Responses were identified in 29(75. 2%) infectors with more than 3 years of infection and the specific T lymphocytes were mainly targeted at three peptides which span from Nef 63 to 101 : EVA7081.43, EVA7081.44, EVAT081.45, EVA7081.47, EVA7081.48 and EVA7081.49. The average magnitude of response in infectors with less than 1 year of infection was 284. 13 SFC/106 PBMC. The average magnitude of response in infectors with more than 3 years of infection was 152. 44 SFC/106 PBMC. There was a significant difference between the two groups (U = 91. 000, P = 0. 002). Conclusions HIV-1recombinant subtype B/C infectors at different stages of diseases (less than 1 year and more thank 3 years) can recognize central region of Nef. The magnitude of Nef-specific IFN-γ secretion T lymphocyte responses in this cohort gradually decrease with disease progression. Key words: HIV infections; HIV-1; Nef Gene products,human immunodeficiency virus; T-lymphocytes; Interferon type Ⅱ