Chemotaxis Induced by CXCL6/GCP‑2 and Neutralization by Human CXCL6/GCP‑2 Antibody. Recombinant Human CXCL6/|
GCP‑2 (Catalog # 333-GC) chemoattracts the BaF3 mouse pro‑B cell line transfected with human CXCR2 in a dose-dependent manner (orange line). The amount of cells that migrated through to the lower chemotaxis chamber was measured by Resazurin (Catalog # AR002). Chemotaxis elicited by Recombinant Human CXCL6/
GCP‑2 (80 ng/mL) is neutralized (green line) by increasing concentrations of Goat Anti-Human CXCL6/GCP‑2 Antigen Affinity-purified Polyclonal Antibody (Catalog # AF333). The ND50 is typically 0.8‑4.0 µg/mL.
GCP-2 (granulocyte chemotactic protein-2) also known as CXCL6, is a CXC chemokine initially isolated as a neutrophil chemoattractant from the MG-63 osteosarcoma cell line. Among human CXC chemokines, GCP-2 is most closely related to ENA-78 (78% amino acid (aa) sequence identity in the mature peptide region and 86% identity in the signal sequence). The structure and sequence of the genes for human GCP-2 and ENA-78 also exhibit close similarity suggesting the two genes may have originated from a gene duplication. LIX (LPS-induced CXC chemokine) was initially cloned as a gene induced by LPS in mouse fibroblasts. The predicted LIX protein sequence is identical to a previously purified mouse protein designated mouse GCP-2 based on its amino sequence similarity (60% sequence identity) to human GCP-2. Mouse GCP-2/LIX is also 54% identical with human ENA-78 at the amino acid sequence level.
Human GCP-2 cDNA encodes a propeptide of 114 amino acid residues with a predicted 37 aa residue signal peptide and 77 aa residue mature protein. Several forms of natural GCP-2 have been isolated from MG-63 conditioned media, indicating that GCP-2 undergoes limited processing at both the N- and C-termini. Human GCP-2 is a primary response gene whose induction by cytokines is attenuated by dexamethasone.
Human GCP-2 and mouse GCP-2/LIX have been shown to chemoattract and activate neutrophils, but not eosinophils and monocytes. It is likely that GCP-2 activities are mediated via the human or mouse CXCR2.