GENETIC CO-INACTIVATION OF MACROPHAGE-TROPIC AND T-TROPIC HIV-1 CHEMOKINE CORECEPTORS CCR-5 AND CXCR-4 BY INTRAKINES

CC-chemokine receptor (CCR)-5 is the principal coreceptor for the entr y of macrophage (M)-tropic HIV-1 viruses into a cell, while CXC-chemok ine receptor (CXCR)-4 is the principal coreceptor for T cell line (T)- tropic HIV-1. In this study, we utilized a novel intracellular chemoki ne (intrakine) strategy to co-inactivate genetically both CCR-5 and CX CR-4 in human lymphocytes. The principle of co-inactivation of CCR-5 a nd CXCR-4 was illustrated by targeting the CC-intrakine and CXC-intrak ine to the lumen of the endoplasmic reticulum (ER) for intracellular b lockade of the transport of newly synthesized chemokine coreceptors to the cell surface. The lymphocytes with the phenotypic knock-out of CC R-5 and CXCR-4 were found broadly to resist the infection of M-tropic, T-tropic and dual-tropic HIV-1 viruses. Moreover, the transduced lymp hocytes retained normal cell features, including the responsiveness to mitogen and recall antigen stimulation. Thus, this study, to our know ledge, is the first to demonstrate that genetic co-inactivation of the M- and T-tropic HIV-1 principal coreceptors in lymphocytes or other c ells could be a viable strategy for the long-term control of HIV-1 inf ection.