GCP-2/CXCL6 Protein, Human (HEK293, His)

CXCL6 (also known as GCP-2) is a CXC chemokine expressed by macrophages and epithelial and mesenchymal cells during inflammation. Through binding and activation of its receptors (CXCR1 and CXCR2), it exerts neutrophil-activating and angiogenic activities. In addition, CXCL6 also has antibacterial effects^[1][3].
CXCL6 is an ELR-positive CXC chemokine with a length of 77 amino acids. The NH2-terminal glutamic acid-leucine-arginine (ELR) motif is characteristic of CXC chemokines interacting with the G-protein-coupled receptors CXCR1 and CXCR2. The ELR+ CXC family which includes IL-8, the growth-regulated oncogenes (GRO-α,-β-γ), and ENA-78. The structure of CXCL6 is >75% homologous to ENA-78, but is unique in that it binds with high-affinity to both CXCR1 and CXCR2. GCP-2, similar to IL-8, activates target cells by binding to CXCR-1 and CXCR-2. Both receptors are expressed by neutrophil granulocytes, but not by other blood-derived cells, such as lymphocytes or monocytes. Activation of endothelial cells by CXCL6 causes a mitogenic response, resulting in angiogenesis. CXCL2 is expressed by epithelial cells of the airways, eyes, gastrointestinal tract, mammary glands, tonsils, macrophages, and mesenchymal cells, in particular during inflammation. Lipopolysaccharides (LPS) and the proinflammatory cytokines TNF-α and IL-1β up-regulate the expression of CXCL6, while gamma interferon has a down-regulating effect^[1][2][3].
CXCL6 mediates several processes such as inflammation, immunoreaction, cell growth, and metastasis through interaction with the chemokine receptors CXCR1 and CXCR2 in humans. CXCL6 possesses potent chemotactic and proangiogenic properties. CXCL6 is over expressed in colorectal, breast, lung and thyroid cancers. In addition, CXCL6 shows antibacterial activity against gram-positive and gram-negative pathogenic bacteria of relevance to mucosal infections is seen at submicromolar concentrations^[1][2][3].

Recombinant CXCL6 (10 ng/mL) significantly inhibits both Sirt3 mRNA and protein levels, however, the AKT and FOXO3a phosphorylation significantly increased in human brain microvascular endothelial cells (HBMECs)^[2].
Recombinant human CXCL6 (0 ng/mL, 0.1 ng/mL, 1 ng/mL, 10 ng/mL, 10 ng/mL; 72 h) elicites enhanced proliferation of HUVECs in a dose-dependent manner, and co-culture with fibroblasts caused significantly enhanced HUVEC proliferation. Recombinant CXCL6 also promotes the proliferation of HUVECs in a concentration-dependent manner^[4].
Recombinant human CXCL6 (0 ng/mL, 0.1 ng/mL, 1 ng/mL, 10 ng/mL, 10 ng/mL; 24 h) significantly promotes cancer cell invasion in HT-29 cells^[4].