CCR5 and HIV-1 infection: To investigate their susceptibility or resistance to HIV-1 infection, CCR5-/CR1, CCR5-/CR2 and CCR5-/CR3 cells along with mock-transduced TZM.bl cells were infected with a panel of 5 HIV-1 pseudotypes and one retroviral control in a single-round infectivity assay [37], [41].