CCR5 and HIV-1 infection: For example, treatment of CD4+ lymphocytes or their progenitor cells with ZFN, TALENs, or CRISPR/Cas9 designed to knock out the C-C chemokine receptor type 5 (CCR5) coreceptor of HIV was demonstrated to effectively protect cells from HIV-1 infection in vitro [8,9,10,11], in mouse model [8], or in clinical trials [12] (Sangamo Bioscience reports).