Agrawal Lokesh, Maxwell Christina R, Peters Paul J, Clapham Paul R, Liu Sue M, Mackay Charles R, Strayer David S
Department of Pathology and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
J Gen Virol. 2009 Mar;90(Pt 3):710-722. doi: 10.1099/vir.0.006205-0.
CCR3 has been implicated as a co-receptor for human immunodeficiency virus type 1 (HIV-1), particularly in brain microglia cells. We sought to clarify the comparative roles of CCR3 and CCR5 in the central nervous system (CNS) HIV-1 infection and the potential utility of CCR3 as a target for manipulation via gene transfer. To target CCR3, we developed a single-chain antibody (SFv) and an interfering RNA (RNAi), R3-526. Coding sequences for both were cloned into Tag-deleted SV40-dervied vectors, as these vectors transduce brain microglia and monocyte-derived macrophages (MDM) highly efficiently. These anti-CCR3 transgenes were compared to SFv-CCR5, an SFv against CCR5, and RNAi-R5, an RNAi that targets CCR5, for the ability to protect primary human brain microglia and MDM from infection with peripheral and neurotropic strains of HIV-1. Downregulation of CCR3 and CCR5 by these transgenes was independent from one another. Confocal microscopy showed that CCR3 and CCR5 co-localized at the plasma membrane with each other and with CD4. Targeting either CCR5 or CCR3 largely protected both microglia and MDM from infection by many strains of HIV-1. That is, some HIV-1 strains, isolated from either the CNS or periphery, required both CCR3 and CCR5 for optimal productive infection of microglia and MDM. Some HIV-1 strains were relatively purely CCR5-tropic. None was purely CCR3-tropic. Thus, some CNS-tropic strains of HIV-1 utilize CCR5 as a co-receptor but do not need CCR3, while for other isolates both CCR3 and CCR5 may be required.
CCR3被认为是1型人类免疫缺陷病毒（HIV-1）的共受体，尤其是在脑小胶质细胞中。我们试图阐明CCR3和CCR5在中枢神经系统（CNS）HIV-1感染中的比较作用，以及CCR3作为基因转移操纵靶点的潜在效用。为了靶向CCR3，我们开发了一种单链抗体（SFv）和一种干扰RNA（RNAi），即R3-526。两者的编码序列都被克隆到缺失Tag的SV40衍生载体中，因为这些载体能高效转导脑小胶质细胞和单核细胞衍生的巨噬细胞（MDM）。将这些抗CCR3转基因与SFv-CCR5（一种针对CCR5的SFv）和RNAi-R5（一种靶向CCR5的RNAi）进行比较，以研究它们保护原代人脑小胶质细胞和MDM免受外周和嗜神经HIV-1毒株感染的能力。这些转基因对CCR3和CCR5的下调作用相互独立。共聚焦显微镜显示，CCR3和CCR5在质膜上彼此共定位，且与CD4共定位。靶向CCR5或CCR3在很大程度上保护了小胶质细胞和MDM免受多种HIV-1毒株的感染。也就是说，一些从CNS或外周分离出的HIV-1毒株，需要CCR3和CCR5才能实现对小胶质细胞和MDM的最佳有效感染。一些HIV-1毒株相对纯粹是嗜CCR5的。没有一个是纯粹嗜CCR3的。因此，一些CNS嗜性的HIV-1毒株利用CCR5作为共受体，但不需要CCR3，而对于其他分离株，可能需要CCR3和CCR5两者。
