Analysis of the exposure of induced HIV glycoprotein epitopes in a potential HIV pseudovirion vaccine
- 作者：Gerard Devitt ; Vanessa Emerson ; Thorsten Pisch ; Oliver T. Keppler ; Valerie Bosch
- 关键词：HIV vaccine ; HIV pseudovirions ; HIV-Env induced epitopes
- 刊名：Vaccine
- 出版年：2007
- 期刊代码：89_0264410x
- 类别：imm
- 出版时间：8 March 2007
- 卷：25
- 期：12
- 页码：2161-2167
- 文件大小：314 K
摘要
Functionally conserved HIV-Env epitopes, which are induced during the process of Env-mediated membrane fusion, represent interesting immunogens, which may elicit broad neutralising antibody responses. In this report, we analyse a pseudovirion (PV)-based HIV vaccine preparation, potentially enriched in such induced Env-conformations. The vaccine has been prepared by mixing and incubating Env-PVs, with incorporated fusion-defective Env, with PVs, which have incorporated functional CD4 and CXCR4 proteins. Here, we demonstrate that three different monoclonal antibodies (CG10, 17b and 48d), recognising a region of gp120 overlapping with the coreceptor binding site, and a further antibody, 8F101, recognising a CD4-induced epitope outside of the coreceptor site, bind to Env molecules in the putative PV vaccine mixture but not at all, or less strongly, to native Env-PVs. In all cases, antibody binding required an interaction of the Env-PVs with CD4 whereas CXCR4 was dispensible. These results confirm that in the PV vaccine preparation, CD4-induced Env epitopes are accessible and that these, as well as other induced epitopes “downstream” from CD4 binding, may function as immunogens to elicit potentially cross-neutralising humoral immune responses.