Tersmette M, van Dongen J J, Clapham P R, de Goede R E, Wolvers-Tettero I L, Geurts van Kessel A, Huisman J G, Weiss R A, Miedema F
Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands.
Virology. 1989 Feb;168(2):267-73. doi: 10.1016/0042-6822(89)90266-3.
Human immunodeficiency virus (HIV) infection was studied by means of CD4-expressing human-murine T-cell hybrids, containing a variable amount of human chromosomes. Fusion of the HPRT- murine cell line BW5147 with human T-cell acute lymphoblastic leukemia or normal human blood cells resulted in a panel of human-murine T-cell hybrids. For this study, we used four hybrids containing all or several human chromosomes, which all expressed the CD4 antigen, as assessed by different anti-CD4 monoclonal antibodies (e.g., OKT4A, Leu-3a, and MT151) and, in addition, a variable number of other human T-cell antigens. For infection, HTLV-IIIB-infected H9 cells, pretreated with mitomycin C, and cell-free concentrated supernatants from these cells were used. In cells of inoculated cultures of the CD4+ T-cell hybrids, no viral antigen could be demonstrated. Culture supernatants of inoculated hybrids, except for an initial rise due to the virus inoculum, never showed reverse transcriptase activity above background. Cocultivation of these cell cultures with H9 cells did not result in detectable virus replication. Cocultivation of CD4-expressing hybrid cells with HIV-infected cells did not result in syncytium formation. Moreover, these hybrids were resistent to infection with vesicular stomatitis virus (VSV)-HIV pseudotypes. These findings imply that expression of the CD4 antigen on the cell surface is not sufficient for productive infection with HIV. The infectivity block observed in these hybrids seems to occur at the level of virus penetration, presumably at the stage of membrane fusion events.
利用表达CD4的人鼠T细胞杂交体对人类免疫缺陷病毒（HIV）感染进行了研究，这些杂交体含有数量不等的人类染色体。HPRT-鼠细胞系BW5147与人T细胞急性淋巴细胞白血病细胞或正常人血细胞融合，产生了一组人鼠T细胞杂交体。在本研究中，我们使用了四个含有全部或几条人类染色体的杂交体，通过不同的抗CD4单克隆抗体（如OKT4A、Leu-3a和MT151）评估，它们均表达CD4抗原，此外还表达数量不等的其他人类T细胞抗原。对于感染实验，使用了经丝裂霉素C预处理的HTLV-IIIB感染的H9细胞以及这些细胞的无细胞浓缩上清液。在接种的CD4+T细胞杂交体培养物的细胞中，未检测到病毒抗原。接种的杂交体的培养上清液，除了因病毒接种物导致的最初升高外，从未显示出高于背景的逆转录酶活性。这些细胞培养物与H9细胞共培养未导致可检测到的病毒复制。表达CD4的杂交细胞与HIV感染细胞共培养未导致合胞体形成。此外，这些杂交体对水泡性口炎病毒（VSV）-HIV假型感染具有抗性。这些发现表明，细胞表面CD4抗原的表达不足以实现HIV的有效感染。在这些杂交体中观察到的感染阻断似乎发生在病毒穿透水平，大概是在膜融合事件阶段。
