摘要目的:通过突变的方式构建含有鼠 Thy1.1基因或鼠 Thy1.2基因的HIV-1 CRF07_BC感染性克隆，建立CRF07_BC亚型体外竞争试验。 方法:用鼠 Thy1.1基因和鼠 Thy1.2基因替换CRF07_BC亚型感染性克隆pXJDC6291-13 Nef区前218个碱基，构建成CRF07_BC感染性克隆BCEA1和BCEA2质粒。BCEA1和BCEA2进行293T细胞转染后获得病毒，测定病毒滴度，以等比例病毒含量共感染PM1细胞，在感染的第3、4、5、6天收集细胞并用 Thy1.1和 Thy1.2特异性抗体标记细胞，并进行流式细胞检测病毒适应性。通过"TFitness"程序(http：//bis.urmc.rochester.edu/vFitness)计算病毒相对适应性。并观察耐药位点K103 N、多态性位点K166R相对于CRF07_BC亚型相对适应性的影响。 结果:CRF07_BC亚型BCEA1和BCEA2两病毒的相对适应性(1+s)结果为1.06±0.23693，无统计学差异，建立了CRF07_BC亚型体外生长竞争性试验。利用该体外生长竞争试验验证K103 N和K166R突变株与野生株的相对适应性，BCEA2-K103 N/BCEA1相对适应性是0.728282±0.16608、BCEA2-K166R/BCEA1是0.883385±0.19023、BCEA2-K103 N+K166R/BCEA1是0.804604±0.06164。K103耐药位点突变株与野生株相对适应性存在统计学差异。结论:建立HIV-1 CRF07_BC病毒适应性的体外生长竞争试验，基于该体外竞争试验，HIV-1 K103 N的耐药毒株的病毒适应性降低。

abstractsObjective:To establish an in vitro growth competition assay using HIV-1 CRF07_BC infectious clone containing the mouse Thy1.1 gene or Thy1.2 gene. Methods:The mouse Thy1.1 gene and Thy1.2 gene were used to replace the 218 bases of Nef region of the CRF07_BC infectious clone (pXJDC6291-13) and construct the CRF07_BC infectious clones BCEA1 and BCEA2 plasmid. BCEA1 and BCEA2 plasmids were transfected into 293T to obtain the virus and the viral titration was measured. PM1 cells were co-infected with an equal virus. On the 3 rd to 6 th day of infection the cells were collected and labeled with specific antibodies Thy1.1 and Thy1.2. The viral fitness was detected by flow cytometry. Through "TFitness" (http: //bis.urmc.rochester.edu/vFitness) the relative viral fitness was calculated. The influence K103 N and K166R on the relative fitness of HIV-1 CRF07_BC were observed. Results:The relative fitness (1+ s) of CRF07_BC subtypes BCEA1 and BCEA2 viruses were 1.06±0.23693, which was not statistically significant. An in vitro growth competition assay for CRF07_BC was established. The in vitro growth competition assay was used to verify the relative fitness of the K103 N and K166R mutant strains to the wild strain. The relative fitness of BCEA2-K103 N/BCEA1 was 0.728282±0.16608, BCEA2-K166R/BCEA1 was 0.883385±0.19023, BCEA2-K103 N+ K166R/BCEA1 was 0.804604±0.06164. The relative fitness of K103 N resistant mutant strain and the wild strain was significantly different.Conclusions:An in vitro growth competition assay for the fitness of HIV-1 CRF07_BC virus was established. Based on the in vitro growth competition assay, the HIV-1 K103 N resistant mutant strain has reduced viral fitness.