CD4 and infection: To test whether the virus released from transfected cells could be inhibited byL-50 under conditions of multiple-cycle growth, virus-containing supernatantsfrom 293T transfections (containing L-50) were used to infect U87.CD4.CXCR4cells (which support multiple rounds of HIV-1 replication) and viral progenywere measured 10 days post-infection.