Cytokine-like protein 1 (CYTL1) is a small widely expressed secreted protein lacking significant primary sequence homology to any other known protein. Cytokine-like 1 (CYTL1) is a novel potential cytokine that was first identified in CD34(+) cells derived from bone marrow and cord blood, and it was also found using our immunogenomics strategy. CYTL1 expression appears to be highest in the hematopoietic system and in chondrocytes; however, maintenance of cartilage in mouse models of arthritis is its only reported function in vivo. Despite lacking sequence homology to chemokines, CYTL1is predicted by computational methods to fold like a chemokine, and has been reported to function as a chemotactic agonist at the chemokine receptor CCR2 in mouse monocyte/macrophages. Recombinant CYTL1 promoted calcium flux in chondrocytes. Cytokine-like protein 1 (Cytl1), had been described as a protein expressed in CD34+ cells, and as a functional secreted protein involved in chondrogenesis and cartilage development.