3,4-DAA is an orally active Anthranilic acid derivative with potent immunosuppressive activities. 3, 4-DAA can alleviate the severity of colitis through inhibiting Th1 cells response, promoting Th2 cytokines expression and inducing CD4⁺CD25⁺ T cells expression^[1]. 3,4-DAA suppressed expression of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) release from EOC20 cells induced by IFN-γ and Lipopolysaccharide^[2].