中文摘要：

目的研究HIV-1感染者不同时期分离的R5毒株的生物学特性。方法采用传统的共培养方法分离并培养HIV-1，用表达CD4和CC趋化因子受体5（CCR5）或CXC趋化因子受体4（CXCR4）的GHOST细胞系，通过流式细胞仪测定病毒辅助受体的利用和感染性，从而判断所分离毒株的CCR5嗜型（R5型毒株）；使用2ng P24病毒量感染正常人分离的外周血单个核细胞（PBMC）．ELISA法检测第1、3、5、7、10、15天的HIV-1 P24抗原．反映病毒复制能力；采用HIV-1核酸荧光定量检测试剂盒测定血浆病毒载量。数据分析采用t检验。结果HIV-1B’亚型感染者22例，其中CD4^＋细胞〉0．2×10^9／I。和CD4^＋细胞≤0．2×10^9／L各11例；昕分离的病毒仅利用CCR5辅助受体，均为R5型毒株．感染性的结果显示．来自CD4^＋细胞≤0．2×10^9／L的11株R5毒株的感染性为（7．3927±d．5842）％，而CD4^＋细胞〉0．2×10^9／L的为（2．6136±1．6105）％，差异有统计学意义（t=3．262，P〈0．05）；两组病毒复制滴度在第7天开始明显上升，培养第7、10、15天，两组病毒复制动力学差异有统计学意义（t值分别为3．771、2．509和2．260；P〈0．05），CD4^＋细胞≤0．2×10^9／L的R5毒株的复制能力较CD4^＋细胞〉0．2×10^9／L的明显增强；CD4^＋细胞≤0．2×10^9／L R5型毒株的病毒载量的对数值为（5．6068±0．8151）拷贝／mL，CD4^＋细胞〉0．2×10^9／L的为（4．7298±0．4316）拷贝／mL，两组差异有统计学意义（t=3．771，P〈0．05）。结论疾病进展过程中。即使病毒的辅助受体利用未从CCR5转变为CXCR4，但病毒的感染性和复制能力已有明显改变。

英文摘要：

Objective To study biological characteristics of R5 tropic human immunodeficiency virus （HIV）-1 strains in different disease stage. Methods Primary clinical viruses were isolated from fresh peripheral blood mononuclear cells （PBMC） using co-culture methods; meanwhile, viral co receptor usage and infectivity were tested using flow cytometry on GHOST （3） cell lines, which expressed CD4 receptor and CC chemokine receptor 5 （CCRS） or CXCR4 coreceptor; to identified CCR5 tropic viruses（R5 tropic strains）, Viral replication kinetics was detected in PBMCs. Plasma viral load was measured using an HIV-1 nucleotidc fluorescence quantifieation assay kit. Results There were 22 individuals with HIV-1 subtype B＇ infection, in which 11 were CD4 〉 0.2 × 10^9/L and 11 were CD4 ≤ 0. 2 × 10^9 / L. All isolated viruses used CCR5 coreceptor and therefore were HIV-1 R5 tropic strains. The infectivity of R5 tropic strains isolated from patients with CD4≤0.2 × 10^9/L was （7. strain from patients with CD4〉0. 2 × 10^9/1. was 392 7±4. 584 2） % ; while the infectivity of R5 tropic （2. 613 6±1. 610 5）%. There were significant statistical difference（t=3. 262, P〈0.05）. The possibility of viral replication became strong after the day 7 post-infection. There was a significant difference of viral replication between two groups in the day 7,10,15 post-infection（t value was 3. 771, 2. 509 and 2. 260 respectively, P〈 0. 05）. The possibility of viral replication was higher in CD4≤0.2 × 10^9/L group than that of CD4〉0.2 × 10^9/L group. The logarithm of viral load was （5. 606 8±0. 815 1） copies/mL in CD4≤0.2 × 10^9/L group and （4. 729 8±0. 431 6） copies/mL in CD4 〉 0. 2 × 10^9/L group. There was a significant difference between two groups（t= 3. 771 ; P〈 0.05）. Conclusion Viral infection and replicatioh are enhanced during progression of disease, even if viral coreceptor usage do not switch from CCR5 to CXCR4.