Objective: The HLA-A*30-B*13-C*06 haplotype is reported to be associated with slow disease progression in the HIV-1-infected Northern Han Chinese population, but the mechanism remains unknown.Design: Gag-specific T-cell responses and gag sequencing were performed in nine B' clade HIV-1-infected HLA-A*30-B*13-C*06-positive slow progressors to understand HLA-associated viral control.Methods: Interferon-gamma ELISPOT assays were performed to determine the Gag-specific T-cell responses and cross-reactivity to variant peptides. Longitudinal HIV-1 gag sequencing was performed at the clonal level.Results: The overlapping peptides (OLP)-48: RQANFLGKIWPSHKGRPGNF (RL42 Gag(434-453)); OLP-2: GQLDRWEKIRLRPGGKKKYR (RL42 Gag(11-30)); OLP-15: VQNLQGQMVHQPISPRTLNA (RL42 Gag(135-154)) and OLP-16: HQPISPRTLNAWVKV-VEEKA (RL42 Gag(144-163)) were dominant in HLA-A *30-B*13-C*06-positive patients. A new epitope [HQPISPRTL (Gag(144-152), HL9)] within OLP-15 and OLP-16 was identified. Results showed that strong cross-reactive responses to multiple immunodominant peptides were associated with better clinical outcomes. In addition, efficient cross-recognition of HL9 autologous variants developed in patients was associated with high CD4(+) T-cell counts. However, two patients who had developed mutations to their dominant responses during the follow-up experienced decrease in CD4(+) T-cell counts. It appears that Gag-specific T-cell responses against one or more unmutated epitopes or cross-recognition of autologous epitope variants contribute to slow disease progression in HLA-A *30-B*13-C*06-positive patients.Conclusion: We conclude that a single 'appropriate' Gag-specific T-cell response appears to be sufficient to protect patients from disease progression. HLA-A*30-B *13-C*06-positive individuals benefited from having a choice of numerous immunodominant gag epitopes for T cells to react. The study offers new insight for future design of T-cell-based HIV-1 vaccine. Copyright (C) 2015 Wolters Kluwer Health, Inc. All rights reserved.

Objective To evaluate the reproducibility of an in-house HIV-1 drug resistance(HIVDR) genotyping test.Methods The reproducibility of an in-house HIVDR genotyping test was evaluated with 204 plasma samples,which had been tested from 2008 to 2010.The samples were randomly selected and retested with the same method.A fragment of HIV pol gene was extracted from plasma samples,amplified and sequenced.Drug resistance-related mutations were identified and interpreted through Stanford HIVdb program,and were compared with the results of previous testing.Results The rates of concordance in the overall resistance and resistance to specific antiretroviral drugs were 98.5%(201/204)and 92.2 %(188/204) between the results of the first and second testing,respectively.One hundred and sixty-seven(81.9%)specimens had same levels of resistance to specific antiretroviral drugs between the two sets of results.However,the discordant drug resistance-related mutations were found in 84 samples,among which 159 discordant codons were discovered.Most(149) of the codons were partially discordant.The inconsistent codons were most frequently found at position 71(13/204,6.4%) of the protease and 103(12/204,5.9%) of the reverse transcriptase(RT), respectively.Ten completely discordant codons were found at position 71 of the protease.Nucleoside reverse transcriptase inhibitor(NRTI) resistance-related sites were found at position 67,69,70,215 and 219 and non-nucleoside reverse transcriptase inhibitor(NNRTI) resistance-related sites were found at position 90,181 and 221 of RT regions,respectively.Conclusions The results revealed high concordance rates in both the incidence and the degree of drug resistance.The reproducibility of the in-house drug genotyping test procedure can be optimized by further standardization and personnel training.

Objective To analyze the character of Pol-specific T lymphocyte responses and identify immunodominant region recognized in Chinese HIV-1 recombinant subtype B/C infectors at different stages of diseases. Methods Eleven Chinese HIV-1 recombinant subtype B/C infectors infected in 18 months, 25 which infected time more than 3 years and 10 HIV-1-seronegative healthy individuals were enrolled. HIV-1-specific T lymphocyte responses were analyzed by an IFN-γ ELISPOT assay against 249 overlapping peptides spanning HIV-1 Pol protein in the present study. Results Pol-specific T lymphocyte responses of IFN-γsecretion were identified in 8 (72.73%) out of 11 infectors infected in 18 months, the specific T lymphocytes are mainly targe-ted at six peptides which amino acid position from Pol 481 to 631 in reverse transcriptase region: Pol5581, Pol5582, Pol5587, Pol5609, Pol5610 and Pol5615. There was a negative correlation between the breadth of re-sponse and peripheral CD4+ T cell count (P=0.0212, r=-0.762) ; Responses were identified in 15 (60%) out of 25 chronic infectors, the specific T lymphocytes are mainly targeted at four peptides which amino acid po-sition from Pol 241 to 295: Pol5521, Pol5525, Pol5526, Pol5531 and another peptide: Pol5638 which amino acid position from Pol 708 to 722 in reverse transcriptase region. There was a positive correlation between the magnitude of Pol-specific IFN-γ secretion T lymphocyte responses and plasma viremia (P = 0.006 95 , r = 0.660) . None of the seronegative healthy individuals gave the positive responses. Conclusion Chinese HIV-1 recombinant subtype B/C infectors at different stages of diseases mainly recognized different re-gions of Pol.

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.

Objective: To investigate high-risk sexual behavior among HIV-positive former commercial blood donors in rural central and eastern China. Methods: From December 2003 to May 2004, a cross-sectional study was conducted to investigate demographic characteristics, sexual behaviors, condom use, and known HIV status among HIV-positive commercial blood donors. A total of 796 subjects were recruited for the study. Results: Of the 796 study subjects, 53.0% (258/487) did not use condoms, 10.9% (53/487) inconsistently used condoms, and 36.1% (176/487) consistently used condoms with a steady sex partner in the past three months. Age (OR, 0.57; 95% CI: 0.39, 0.82), years of education (OR, 1.90; 95% CI: 1.27,2.84) and known HIV status (OR, 1.66; 95% CI: 1.12,2.45) were independently and positively associated with condom use with a steady sex partner. Of those subjects without a steady sexual partner in the past year, 63.6% (14/22) did not use condoms, 9.1% (2/22) inconsistently used condoms, and 27.3% (6/22) consistently used condoms. Conclusion: HIV counseling and education should be focused on HIV-positive blood donors to prevent a secondary spread of HIV through unsafe sexual practices.