亚洲系与非洲系寨卡病毒株对神经胶质细胞感染性及稳定性差异研究

Comparison of the infectivity and stability of Asian versus African lineage Zika virus in glial cells

目的明确亚洲系ZIKV与非洲系ZIKV感染性与稳定性的差异。方法选择亚洲系SZ01与非洲系MR766病毒株在神经胶质细胞中展开研究。使用CCK8法检测SZ01与MR766对星形胶质细胞U251、U87和神经胶质母细胞瘤细胞T98G感染性差异;qRT-PCR或病毒空斑法检测SZ01与MR766在游离状态和感染细胞状态时,对37℃和40℃的耐受能力;最后,通过使用病毒空斑法检测反复冻融对SZ01与MR766稳定性的影响。结果ZIKV对U251、U87的感染性高于T98G,SZ01对星形神经胶质细胞的感染性强于MR766;游离状态下,SZ01对40℃的耐受能力高于MR766;在40℃高温下,SZ01在神经胶质细胞内的增殖速度快于MR766;SZ01对于反复冻融的耐受性高于MR766。结论亚洲系ZIKV的感染性及稳定性均显著高于非洲系ZIKV,或与其持续性感染致病有关。

Infection of pregnant women by Asian lineage Zika virus(ZIKV)is more likely to cause microcephaly in infants than African lineage ZIKV.To further clarify the differences in infectivity and stability between Asian and African lineage ZIKV,we selected Asian lineage SZ01 and African lineage MR766 strains for study in glial cells.First,we examined the difference in infectivity between SZ01 and MR766 on U251 and U87 astrocytes,and T98G glioblastoma cells,by using CCK8 assays.Subsequently,we examined the tolerance of SZ01 and MR766 to 37℃and 40℃in the free and infected cell states,by using qRT-PCR or viral plaque assays.Finally,we examined the effect of repeated freezing and thawing on the stability of SZ01 and MR766 with viral plaque assays.ZIKV had higher infectivity in U251 and U87 than T98G,and SZ01 was more infectious to astrocytes than MR766.SZ01 tolerated 40℃better than MR766 in the free state.SZ01 proliferated faster than MR766 in glial cells at 40℃.The tolerance of SZ01 to repeated freezing and thawing was higher than that of MR766.The above findings suggest that the infectivity and stability of Asian lineage ZIKV are significantly higher than those of African lineage ZIKV,possibly because of its persistent infection and pathogenicity.