Cook D G, Fantini J, Spitalnik S L, Gonzalez-Scarano F
Department of Neurology, University of Pennsylvania Medical Center, Philadelphia 19104-6146.
Virology. 1994 Jun;201(2):206-14. doi: 10.1006/viro.1994.1287.
The primary receptor for the human immunodeficiency virus (HIV) is the CD4 molecule. However, a large body of evidence has demonstrated that some cells that do not express the CD4 receptor can be infected by HIV-1 and HIV-2, indicating that an alternative mechanism of infection must exist for some cell types. Recently it was reported that antibodies against the glycosphingolipid, galactosylceramide (Gal beta 1-1'Cer;GalCer), blocked infection of several CD4 negative cell lines derived from the brain and colon. The hypothesis that GalCer might be involved in the process of HIV entry into these cells was further supported by the finding that recombinant gp120 bound GalCer with high affinity in a high performance thin layer chromatography (HPTLC) binding assay. We have examined the interactions between GalCer and gp120, and found that the oligosaccharides that constitute a large proportion of the molecular mass of this glycoprotein are not involved in binding to this glycolipid. Furthermore, using a panel of monoclonal and monospecific antibodies we have determined that gp120 binds GalCer, and the related molecule 3' sulfo galactosylceramide (sulfatide), at a site that is conformationally close to the its principal neutralizing domain (V3 loop) or at the V3 loop itself.
人类免疫缺陷病毒（HIV）的主要受体是CD4分子。然而，大量证据表明，一些不表达CD4受体的细胞也能被HIV - 1和HIV - 2感染，这表明某些细胞类型必定存在另一种感染机制。最近有报道称，针对糖鞘脂半乳糖基神经酰胺（Galβ1 - 1'Cer；GalCer）的抗体可阻断源自脑和结肠的几种CD4阴性细胞系的感染。在高效薄层色谱（HPTLC）结合试验中发现重组gp120与GalCer具有高亲和力，这一发现进一步支持了GalCer可能参与HIV进入这些细胞过程的假说。我们研究了GalCer与gp120之间的相互作用，发现构成该糖蛋白大部分分子量的寡糖并不参与与这种糖脂的结合。此外，我们使用一组单克隆和单特异性抗体确定，gp120在一个构象上靠近其主要中和结构域（V3环）或在V3环本身的位点与GalCer及相关分子3' - 磺基半乳糖基神经酰胺（硫苷脂）结合。
