N‐acetylprocainamide is a less potent inducer of t cell autoreactivity than procainamide

We have reported that an inhibitor of DNA methylation, 5‐azacytidine, makes cloned, antigen‐specific CD4 + T cells autoreactive, and that procainamide and hydralazine mimic this effect. Those results suggested that procainamide and hydralazine may induce autoimmunity by inhibiting DNA methylation and causing T cell autoreactivity. We report now that N‐acetylprocainamide, a procainamide derivative that does not induce lupus, is also a DNA methylation inhibitor, but it is 100 times less potent than procainamide in inducing T cell autoreactivity.