Analysis of hepatitis C virus (HCV) subtypes in HIV/HCV co-infected and HCV mono-infected individuals in Guangdong province / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To explore the transmission routes, genotypes/subtypes distribution and genetic character of HCV in HIV/HCV co-infected and HCV mono-infected individuals in Guangdong Province.</p><p><b>METHODS</b>Reverse transcription (RT) nested PCR was performed to amplify the HCV NS5B gene region from 95 HIV/HCV co-infected and 99 HCV mono-infected individuals lived in Guangdong province. The PCR products were then sequenced for HCV subtyping. Genetic analysis was done by MEGA4 software.</p><p><b>RESULTS</b>(1) HIV/HCV co-infected individuals infected HCV mostly through injection drug use (IDU, 78.9%), the HCV subtypes were identified as 6a (53.7%), 3a (17.9%), 1b (15.8%), 3b (11.6%) and 1a (1.0%) respectively, the genetic distance within subtype 1b was longer than those within other subtypes, the predominant HCV subtype in HIV/HCV co-infected individuals infected through IDU was 6a (60.0%). (2) HCV mono-infected individuals infected HCV mostly through blood or blood products transfusions (80.8%), the HCV subtypes were identified as 1b (67.7%), 6a (17.2%), 3a (6.1%), 2a (5.0%), 3b (2.0%), 4a (1.0%) and 5a (1.0%) respectively, the genetic distance within subtype 1b was also longer than those within other subtypes, the predominant HCV subtype in HCV mono-infected individuals infected through blood or blood products transfusions was 1b (76.2%).</p><p><b>CONCLUSION</b>The diversity of HCV subtypes in HIV/HCV co-infected and HCV mono-infected individuals in Guangdong Province was high, both the major transmission route and HCV subtype between HIV/HCV co-infected individuals and HCV mono-infected individuals were different.</p>

Study on human leukocyte antigen-[ restriction sites in human immunodeficiency virus type 1 specific CD8~+T cell responses / 中华传染病杂志

Objective To investigate human immunodeficiency virus type 1 (HIV 1)specific CD8'T cell responses and related human leukocyte antigenⅠ(HLA-I)restriction sites.Methods Four Epstein-Barr virus (EBV)strains-transformed B-lymphoblastoid cell lines (BLCL)from periph eral blood monocytes (PBMC)of 4 healthy individuals were established.Using synthesized peptides in HIV-1 Gag,Vif and Nef regions as epitopes and using BLCL as antigen presenting cells (APC), the frequency of interferon-7(IFN-?)secreting cells in CD8 T cells from a HIV-infected long term nonprogressor by enzyme-linked immunospot (ELISPOT)assay in vitro were assessed.Moreover, matching analysis of HI.A-Ⅰrestriction sites were performed.Results HIV-1 epitopes were presen ted restrictively by HLA-Ⅰmolecules in specific CD8 T cell responses,and this antigen presenting had high specificity.HLA-Ⅰrestriction sitesA03,A26,C04andC08 contributed to presentepitopes in HIV-1 C-ag region,A03 and C08 to HIV-1 Nef as well.Conclusion HLA-Ⅰrestriction sites may include A03,A26,C04 and C08 in HIV-1 Gag region,and A03,C08 in Nef region.

Immunodominance in CD8+ T cell responses to HIV-1 synthesized epitopes / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate immunodominance in CD8+ T cell responses to human immunodeficiency virus type 1 (HIV-1) epitopes.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>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.</p>