CD4 and uveitis: Immune balance can be achieved by regulating the secretion of cytokines and may contribute to the treatment of uveitis.[20] NK cells have activated and inhibitory receptors on their surface to regulate cell status,[31] CD94/NKG2A is one of the most important inhibitory molecules,[32] that CD94/NKG2A regulates the expression of in CD4 and CD8 + T cells, thereby regulating cytotoxic activity and cytokine production.