Increased concentration of IL-10, a growth and differentiation factor for activated B lymphocytes, has been found increased in vitreous fluids of PVRL patients [75], in contrast with the increased concentration of IL-6 characteristic of uveitis, for which many authors have indicated that an IL-10/IL-6 ratio greater than 1.0 is useful for the diagnosis of PVRL. This evidence concerns the gene IL10 and uveitis.