All three isoforms of GRO are CXC chemokines that can signal through the CXCR1 or CXCR2 receptors. The GRO proteins chemoattract and activate neutrophils and basophils. GRO/MGSA also stimulates mitogenesis in certain human melanoma cells. Recombinant human GRO/MGSA is a 7.8 kDa protein consisting of 73 amino acids including the 'ELR' motif common to the CXC chemokine family that bind to CXCR1 or CXCR2.