CCL3L3 and HIV-1 infection: The affinity of CCL3L1 binding to CCR5 was much higher than that to CCL3 and CCL5, and CCL3L1 is the most potent agonist of CCR5 and suppresses HIV-1 infection [142, 143], whereas CCL7/MCP-3 is the main antagonistic ligand of CCR5.