Growth-regulated Alpha Protein (GRO), also known as CXCL-1, GRO1, MGSA and SCYB1, is a chemokine belonging to the intercrine alpha (Chemokine CXC) family. It is expressed mainly by macrophages, neutrophils and epithelial cells. GRO signals through chemokine receptor CXCR1 and CXCR2, and functions to chemoattract and activate neutrophils and basophils. It is also a hematoregulatory chemokine, which suppresses hematopoietic progenitor cell proliferation. GRO has also been reported to play a role in spinal cord development, angiogenesis, wound healing and tumorigenesis.