CD193 / CCR3 is a G-protein coupled receptor for several chemokines, namely CCL11 (eotaxin), CCL26 (eotaxin-3), CCL7 (MCP-4), or CCL5 (RANTES). It is highly expressed on eosinophils and basophils, and is also detected in TH1 and TH2 cells, as well as in airway epithelial cells. CD193 is the key eosinophil chemokine receptor responsible for regulation of eosinophil migration and function. This receptor may contribute to the accumulation and activation of eosinophils and other inflammatory cells in the allergic airway. It is also known to be an entry co-receptor for HIV-1.