PSMB9 and colitis: While resistance to DSS-induced colitis was observed in single immunosubunit-deficient mice, lacking either β1i/LMP2, β2i/MECL-1 or β5i/LMP7 [15]–[17], we used β2i/MECL-1&β5i/LMP7-deficient T-cells to determine the effects of immunosubunit deficiency in development of T-cell transfer colitis.