マウスCCL21/6Ckine測定ELISAキット Quantikine Mouse CCL21/6Ckine ELISA Kit

CCL21, also known as 6Ckine, TCA-4, SLC, Exodus-2, and A21, is a 12 kDa homeostatic chemokine that plays an important role in adaptive immune responses and inflammation. Unlike other CC chemokines, mouse CCL21 has a 36 amino acid (aa) C-terminal extension which mediates its attachment to carbohydrate structures and extracellular matrix components. Mature mouse CCL21 shares 71% and 84% aa sequence identity with human and rat CCL21, respectively. In mice, three genes encode CCL21, with B and C forms being identical and the A form carrying serine at aa 65 instead of leucine. Both human and mouse CCL21 signal through the chemokine receptor CCR7, while mouse CCL21 additionally can signal through CXCR3. CCL21 is constitutively presented on initial lymphatic vessels, high endothelial venules (HEV), and lymph node dendritic cells (DC). Immobilized CCL21 promotes the docking of DC to lymphatic vessels and the retention of T cells by lymph node DC, resulting in T cell priming for activation. DC interaction with the anchored chemokine can induce CCL21 cleavage and release of an 8 kDa fragment that lacks the C-terminal extension. During chronic inflammation or tissue damage, CCL21 is upregulated on local vascular endothelial cells, macrophages, T cells, and neurons. In these settings, it promotes fibrosis, inflammatory cytokine production, and neuropathic pain. The soluble chemokine is elevated in rheumatoid arthritis synovial fluid and in the serum of coronary artery disease patients. CCL21 has been shown to exert either angiogenic or angiostatic effects. These effects, in combination with the ability of CCL21 to attract immune suppressor cells (Treg and MDSC) to a tumor site can have positive or negative effects on tumor progression.