Janas Alicia M, Dong Chunsheng, Wang Jian-Hua, Wu Li
Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
Virology. 2008 Jun 5;375(2):442-51. doi: 10.1016/j.virol.2008.01.044. Epub 2008 Mar 10.
Human immunodeficiency virus type 1 (HIV-1) enters dendritic cells (DCs) through endocytosis and viral receptor-mediated fusion. Although endocytosis-mediated HIV-1 entry can generate productive infection in certain cell types, including human monocyte-derived macrophages, productive HIV-1 infection in DCs appears to be dependent on fusion-mediated viral entry. It remains to be defined whether endocytosed HIV-1 in DCs can initiate productive infection. Using HIV-1 infection and cellular fractionation assays to measure productive viral infection and entry, here we show that HIV-1 enters monocyte-derived DCs predominately through endocytosis; however, endocytosed HIV-1 cannot initiate productive HIV-1 infection in DCs. In contrast, productive HIV-1 infection in DCs requires fusion-mediated viral entry. Together, these results provide functional evidence in understanding HIV-1 cis-infection of DCs, suggesting that different pathways of HIV-1 entry into DCs determine the outcome of viral infection.
1型人类免疫缺陷病毒（HIV-1）通过内吞作用和病毒受体介导的融合进入树突状细胞（DCs）。尽管内吞作用介导的HIV-1进入在某些细胞类型中可产生有效感染，包括人单核细胞衍生的巨噬细胞，但DCs中的有效HIV-1感染似乎依赖于融合介导的病毒进入。DCs中内吞的HIV-1是否能引发有效感染仍有待确定。我们使用HIV-1感染和细胞分级分离测定法来测量有效病毒感染和进入，结果表明HIV-1主要通过内吞作用进入单核细胞衍生的DCs；然而，内吞的HIV-1不能在DCs中引发有效HIV-1感染。相比之下，DCs中的有效HIV-1感染需要融合介导的病毒进入。这些结果共同为理解HIV-1对DCs的顺式感染提供了功能证据，表明HIV-1进入DCs的不同途径决定了病毒感染的结果。
