CCR5 enhances both HDR and SSA DNA repair. CCR5 enhances both HDR and SSA DNA repair. A–C, Gene expression was determined from cells (CCR5+ vs. CCR5− cells derived by FACS sorting, Supplementary Fig. S5) using qRT-PCR. The relative abundance of the transcripts participating in DNA damage/repair are shown as mean ± SEM for n = 4. D, Schematic representation of the DNA repair reporter (DR-GFP) for HDR. E, HDR activity was increased in CCR5+ SUM-159 cells. The cells were cotransfected with the plasmid encoding I-SceI and the I-SceI–based DNA repair reporter DR-GFP or SA-GFP, for SSA (F) and stained with APC-labeled anti-CCR5 antibody. GFP+ cells, generated by HDR of I-SceI–induced double-strand DNA, were sorted by FACS into CCR5− and CCR5+ populations (Supplementary Fig. S8). The percentage of DR-GFP+ cells or SA-GFP–positive cells were calculated and normalized with the transfection efficiency control (NZ-GFP). G, The percentage of DR-GFP+ and SA-GFP+ cells was increased in CCR5-expressing cells compared with vector control cells. Xuanmao Jiao et al. Cancer Res 2018;78:1657-1671 ©2018 by American Association for Cancer Research