甲基-β-环湖精对人类疱疹病毒6型感染性的影响

Effects of Methyl-β-cyclodextrin on Human Herpesvirus-6A Infectivity

目的了解甲基-β-环糊精对人类疱疹病毒6型包膜胆固醇含量及其病毒感染性的影响．方法用不同浓度的甲基环糊精作用于HHV-6AGS株，经20％蔗糖缓冲液梯度离心，去除甲基-β-环糊精并纯化病毒，分剐进行病毒胆固醇含量的测定及感染HSB-2细胞，然后采用IFA法和免疫蛋白杂交等方法检测病毒受甲基环湖精作用后，其对靶细胞的结合、融合、进入的影响以及包膜糖蛋白的表达、结果甲基-β-环糊精能去除HHV-6A包膜胆固醇，病毒的感染性遭到了破坏，但可以被外源性胆固醇所恢复、HHV-6A结合宿主细胞的能力稍微受到影响，但其感染性及诱导细胞融合的能力显著减弱，包膜糖蛋白的表达不受影响．结论HHV-6A包膜胆固醇在细胞融合过程中起着重要作用，同时也是病毒进入宿主细胞的关键因素．

Objective To understand the effect of methyl-β-cyclodextrin（MβCD） on the content of cholesterol in the envelope of Human Herpesvirus-6 （HHV-6） and viral infectivity. Methods HHV-6A GS strains were treated with different concentrations of MflCD. The treated virus was subjected to ultracentrifugation through 20 % sucrose cushion to remove MβCD and phrified virus, then the cholesterol content of treated HHV-6A was measured, HSB-2 cells were infected by treated HHV-6A respectively. The roles of HHV-6A binding host cells, induced cell-fusion and the ability of entry were examined by using IFA and Western blotting post HHV6A cholesterol depletion. Results MflCD could reduce cholesterol in HHV-6 envelope, and viral infectivity was abolished, but it could be rescued by the addition of exogenous cholesterol. HHV-6 binding was affected slightly by MβCD treatment. In contrast, envelope cholesterol depletion markedly affected HHV-6 infectivity and HHV-6-induced cell fusion. The expression of envelope glycoproprotein was not affected. Conclusion These results suggest that the cholesterol present in the HHV-6 envelope plays a prominent role in the fusion process and is a key component in viral entry.