CD193, also known as C-C motif chemokine receptor 3 (CCR3), is a member of the G protein-coupled receptor (GPCR) family, characterized by its seven-transmembrane structure. It is a high-affinity receptor for various chemokines, including eotaxin-1 (CCL11), eotaxin-2 (CCL24), eotaxin-3 (CCL26), MCP-3 (CCL7), MCP-4 (CCL13), and RANTES (CCL5). CD193 is highly expressed on eosinophils, basophils, and airway epithelial cells, and is also detected in CD4+ T cells, mast cells, monocytes, platelets, and CD34+ hematopoietic progenitor cells. This receptor plays a crucial role in mediating the migration and activation of eosinophils and other inflammatory cells, contributing to allergic responses and inflammatory processes in conditions such as asthma and allergic rhinitis. Additionally, CD193 has been identified as a co-receptor for HIV-1 entry into cells.