目的：通过流式细胞术观察拯救CIAV M突变株对宿主细胞MSB1的生长周期及凋亡的影响。方法：拯救CIAV M突变株接于MDCC-MSB1细胞系（试验组），并相应设立阴性组（正常SPF鸡肝脏细胞液），阳性组（CUX-1标准毒株），进行培养24hr-48hr。用PI及FITC Annexin V染色方法，用流式细胞仪测定宿主细胞生长周期及凋亡，并用SPSS13.0进行结果统计学分析。结果：接种拯救CIAV M突变株的宿主细胞G0/G1期的累积细胞百分率为59.33%±4.04%，S期为32.92%±3.65%，G2/M期为7.75%±3.11%，与阴性组相比，G0/G1期细胞累积百分率有所上升；与CUX组相比，G0/G1期有所下降，但结果经统计学分析，差异均不显著（P>0.05）。试验组宿主细胞凋亡率为37.00%±4.65%，与阴性组相比，凋亡率上升，统计学差异显著（P<0.05）；与阳性组相比，凋亡率下降，统计学差异显著（P<0.05）。结论：本次试验结果显示，经过VP3基因突变的CIAV M突变株，经过病毒拯救并回归本动物后，对宿主细胞MSB1的生长周期没有显著的抑制，但能引起宿主细胞的显著性凋亡，且凋亡程度与CUX-1引起的宿主细胞凋亡率相比有所降低。可以表明，通过VP3密码子移位的基因突变，能够将CIAV的致凋亡作用降低，从而相应降低病毒的致病性，为以后构建CIAV减毒疫苗株奠定理论基础。

objective: To observe the effect of rescued mutant CIAV on the host cell cycle and apoptosis of MDCC-MSB1 through flow cytometry. Methods: MDCC-MSB1 was inoculated with rescued mutant CIAV M strain after 24 hours or 48 hours, while the negative control and the positive control were established. Cell cycle phase and apoptosis of MSB1 was detected by flow cytometry(FCM) with PI staining and FITC Annexin V staining. The acquirement was analysis by SPSS 13.0. Results: The percentage of G0/G1 phase of MDCC-MSB1 cultured with rescued mutant CIAV M strain was 59.33%±4.04%，the percentage of S phase was 32.92%±3.65% and that of G2/M phase was 7.75%±3.11%. The percentage of G0/G1 phase of the test group was larger than that of the negative control, in contrast to the positive control, however the differences were not markable(P>0.05). The apoptosis rate of MDCC-MSB1 cultured with rescued mutant CIAV M strain was 37.00% ± 4.65%, higher than that of negative control, while lower than the positive group, and the differences were significant(P <0.05). Conclusion: The results showed that the inhibition of the host cell cycle by rescued mutant CIAV M strain was not noticeable. The apoptosis of the host cell induced by vp3 gene mutation of CIAV was obvious. The consequence intimated that the vp3 gene mutation of CIAV reserved some characteristics of the virus pathogenicity, which can cause the lower apoptosis rate of cells compared to that of CUX-1, and the fundament theory was established through this study.