Controversially, in a context of diabetic retinopathy, diabetic mice lacking IFN-γ showed a more than two-time increase in the mRNA expression of vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1), retinoic-acid-receptor-related orphan nuclear receptor gamma (ROR-γt), a transcription factor of immune cells T helper (Th) 17 cells, and a more than ten-times increase in splenic IL-17-producing CD4+ cells in comparison to diabetic mice [125]. This evidence concerns the gene ICAM1 and diabetic retinopathy.