S228: ACTIVATED SUMOYLATION RESTRICTS MHC CLASS I ANTIGEN PRESENTATION TO CONFER IMMUNE EVASION IN LYMPHOMA. (23rd June 2022) - Demel, U. M.; Böger, M.; Yousefian, S.; Grunert, C.; Hotz, P.; Haas, S.; Müller, S.; Wirth, M.; Schick, M.; Keller, U.