Immunogen: Synthetic peptide corresponding to aa 3-30 (Y3QVSSPIYDINYYTSEPCQKINVKQIAA30) of the C-terminal domain of human CCR5 (C-C chemokine receptor 5). Percent identity by BLAST analysis: Human (100%); Chimpanzee, Monkey (96%); Orangutan, Baboon (93%); Gorilla (89%).