Table 2. Cellular sources of chemokines and their receptors involved in asthma.
| Chemokine | Cellular source in the lung | Cognate receptor | Receptor expression in asthma |
|---|---|---|---|
| Eotaxin (CCL11) | Epithelial cell, alveolar macrophage,″endothelial cell, smooth muscle cell,″fibroblast, eosinophil, lymphocyte | CCR3 | Eosinophils, basophils, mast cells |
| Eotaxin-2 (CCL24) | Unknown | CCR3 | Eosinophils, basophils, mast cells |
| RANTES (CCL5) | Epithelial cell, smooth muscle, eosinophil | CCR1, CCR3, CCR5 | Eosinophils, monocytes, activated″T cells |
| MCP-1 (CCL2) | Epithelial cell, fibroblast,″alveolar macrophage | CCR2 | Monocytes, macrophages, basophils,″activated T cells |
| MCP-3 (CCL7) | Epithelial cell | CCR1, CCR2, CCR3 | Eosinophils, basophils, monocytes,macrophages, activated T cells |
| MCP-4 (CCL13) | Epithelial cell | CCR2, CCR3 | Eosinophils, basophils, monocytes,″macrophages, activated T cells |
| MDC (CCL22) | Smooth muscle cell, alveolar″macrophage, bronchiolar epithelium | CCR4 | Monocytes, Th2 cells |
| TARC (CCL17) | Bronchiolar epithelial cells | CCR4 | Monocytes, Th2 cells |
| MIP-1α (CCL3) | Epithelial cell | CCR1, CCR5 | Eosinophils, monocytes, activated″T cells |
| IL-8 (CXCL8) | Alveolar macrophage | CXCR1, CXCR2 | Neutrophils |
IL-8, interleukin-8; MCP, monocyte chemoattractant protein; MDC, macrophage-derived chemokine; MIP, macrophage inflammatory protein; RANTES, regulated upon activation, normal, T-cell expressed, and secreted; TARC, thymus and activation-regulated chemokine.