CCL2 and Coats disease: In conclusion, retinal vascular leakage is the fundamental pathological change in Coats disease, accompanied by the increase of various AH cytokines, including VEGF, IL-6, IL-8, MCP-1, MIP-1α, IP-10, VACM-1 and ICAM-1, which is involved in angiogenesis, increased vascular permeability and inflammatory response and may contribute to the pathogenesis and progression of the disease.