Stauber R H, Rulong S, Palm G, Tarasova N I
ABL-Basic Research Program, NCI-FCRDC, Frederick, Maryland, 21702-1201, USA.
Biochem Biophys Res Commun. 1999 May 19;258(3):695-702. doi: 10.1006/bbrc.1999.0511.
Highly fluorescent virions of T- and M-tropic HIV-1 strains were obtained by incorporation of the viral accessory protein Vpr, fused to the green fluorescent protein, in trans. The fluorescent virions displayed normal morphology, were infectious, and could be used for direct visualization of HIV-1 attachment and trafficking in various cell lines. More than 90% of the viral particles were found to enter the cells by direct membrane fusion in T-cells, CD4+ HeLa cells, and macrophages. Visualizing HIV-1 attachment and entry in the absence or presence of CD4 and/or the appropriate coreceptors indicated that CD4 is the major receptor for virus attachment in the case of JR-CSF and NL-4-3 HIV-1 isolates; however, the coreceptors are required for membrane fusion. Internalization of the coreceptor CXCR4 inhibited entry, but did not prevent virus binding suggesting that transient downregulation of the coreceptor(s) may not be the most efficient way of blocking HIV infection in vivo.
通过反式导入与绿色荧光蛋白融合的病毒辅助蛋白Vpr，获得了具有高荧光性的T嗜性和M嗜性HIV-1毒株的病毒颗粒。这些荧光病毒颗粒呈现正常形态，具有感染性，可用于直接观察HIV-1在各种细胞系中的附着和运输情况。发现超过90%的病毒颗粒通过直接膜融合进入T细胞、CD4+ HeLa细胞和巨噬细胞。在存在或不存在CD4和/或适当共受体的情况下观察HIV-1的附着和进入，结果表明，对于JR-CSF和NL-4-3 HIV-1分离株，CD4是病毒附着的主要受体；然而，膜融合需要共受体。共受体CXCR4的内化抑制了进入，但并未阻止病毒结合，这表明共受体的瞬时下调可能不是体内阻断HIV感染的最有效方式。
