About CCR5
This gene encodes a member of the beta chemokine receptor family, which is predicted to be a seven transmembrane protein similar to G protein-coupled receptors. This protein is expressed by T cells and macrophages, and is known to be an important co-receptor for macrophage-tropic virus, including HIV, to enter host cells. Defective alleles of this gene have been associated with the HIV infection resistance. The ligands of this receptor include monocyte chemoattractant protein 2 (MCP-2), macrophage inflammatory protein 1 alpha (MIP-1 alpha), macrophage inflammatory protein 1 beta (MIP-1 beta) and regulated on activation normal T expressed and secreted protein (RANTES). Expression of this gene was also detected in a promyeloblastic cell line, suggesting that this protein may play a role in granulocyte lineage proliferation and differentiation. This gene is located at the chemokine receptor gene cluster region. An allelic polymorphism in this gene results in both functional and non-functional alleles; the reference genome represents the functional allele. Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2015]

About PerCP-Cy5.5
PerCP-Cyanine® 5.5 (PerCP-Cy5.5) is a red-emitting tandem fluorophore that was originally designed to make the PerCP fluorophore more stable and increase signal intensity. The donor molecule, PerCP can be excited by the 488-nm blue laser and and transfers energy to the acceptor molecule, Cy5.5, which emitts light that can be captured with a 695/40 nm bandpass filter. PerCP-Cy5.5 has an excitation peak at 482 nm and an emission peak at 695 nm. There are superior alternatives to PerCP and PerCP-Cy5.5 including BB700, NovaFluor Blue 690 or PerCP-eFluor™ 710