携带Aβ37-42肽段的重组乙肝病毒表面抗原病毒样颗粒的制备

Preparation of a recombinant hepatitis B virus surface antigen virus-like particles expressing Aβ37-42

目的采用杆状病毒表达系统制备携带Aβ37-42肽段的重组乙肝病毒表面抗原(HBsAg)病毒样颗粒(VLPs)。方法将Aβ42分子的C末端6个氨基酸进行3个串联后,插入到HBsAg的113 aa与114 aa之间,利用Bac-to-Bac杆状病毒表达系统,构建表达HBsAg Aβ37-42的重组杆状病毒载体,转染Sf9细胞,Western blot鉴定目的蛋白表达情况,用氯化铯(CsCl)密度梯度超速离心纯化,电镜观察VLPs的形态。结果制备并纯化出HBsAg VLPs和携带Aβ37-42肽段的HBsAg VLPs(HBsAgAβ37-42 VLPs)。结论制备携带Aβ抗原表位的重组HBsAg作为一种阿尔茨海默病(AD)疫苗具有一定的可行性,值得进一步探讨。

Objective To prepare a recombinant hepatitis B virus surface antigen （HBsAg） virus-like particles （VLPs） which carried the peptides of Aβ37-42 by using baculovirus expression system.Methods For constructed an expressing HBsAg Aβ37-42 recombinant bacmid,the encoding sequence of six amino acid short peptide from the carboxy terminus of Aβ42 peptide in triplicate were inserted into HBsAg between 113 aa and 114 aa.When the recombinant bacmid contained the gene of interest was confirmed,it was transfected to Sf9 cells for producing recombinant baculovirus and amplifying the baculoviral stock.The recombinant protein was identified by Western blot.The patterns of the VLPs were observed by transmission electron microscopy after the recombinant protein was purified by using CsCl density gradient centrifugation.Results HBsAg VLPs and HBsAg VLPs expressing Aβ37-42 （HBsAgAβ37-42 VLPs） were successfully constructed and purified.Conclusion The expression of Aβ antigen epitope by HBsAg VLPs is successful and the result is applicable for further in vivo investigation as a candidate vaccine of Alzheimer＇s disease （AD）.