小鼠巨细胞病毒开放阅读框M43突变株体内效应研究

The effects of the mutant of murine cytomegalovirus M43 open reading frame in vivo.

小鼠巨细胞病毒RvM4 3突变株的M4 3开放阅读框中插入Tn -gpt序列。突变株和野生型RqM4 3分别通过唾液腺注射感染免疫缺陷型小鼠CM17SCID ,在感染后不同的时间内分别取出小鼠的唾液腺 ,脾 ,肝 ,肺和肾脏 ,测定M4 3突变株的滴度。实验显示RvM4 3在唾液腺 ,脾 ,和肝中的滴度与野生型无显著性差异 ,但在感染 2 1天后 ,肾脏和肺中的病毒滴度有显著性差异。突变型和野生型感染后影响的死亡时间也存在着显著性差异。结果证实M4 3突变不影响体外细胞的复制 ,但对体内不同器官病毒的生长有不同的影响 ,同时有较弱的降低毒性的作用。研究为探索巨细胞病毒的致病机制提供了新的资料。

RvM43 mutant was generated by insertion Tn-gpt sequence in open reading frame M43 of murine cytomegalovirus(MCMV).The severe combined immunodeficiency SCID mice were infected with RvM43 and wild type virus by salivary glands injection,respectively. The salivary glands,spleens,liver,lungs and kidneys were harvested and sonicted at different timepoint. Viral titers in these organs were determined by plaque assays. Results:showed that RvM43 exhibited a titer similar to that of the wild-type virus in the salivary glands, spleen and livers. In contrast,titers of the mutant virus in the lungs, and kidneys of the infected mice at 21 days postinfection were significantly lower than those of the wild-type virus. Moreover, the death time of mice with RvM43 was significantly delayed than that of mice with wild type virus. The results support that M43 is dispensable for viral growth in NIH 3T3 cells, and suggest M43 mutant has a different effects on different organs in vivo. Moreover, the virulence of the mutant virus appeared to be weakly appeared.