CCR5 and infection: Host-directed approaches aim to render target cells resistant to infection or to enhance antiviral immunity in mucosal compartments (212), CCR5 remains a leading gene-editing target, with multiple studies demonstrating disruption of CCR5 using zinc finger nucleases (ZFNs), TALENs, and CRISPR is feasible in vitro, ex vivo, and in vivo (212–215).