MUC1 and neoplasm: Accordingly, when short epitopes bearing different tumor-associated carbohydrate antigens, such as the Tn determinant (α-O-GalNAc-Ser/Thr), are presented to the immune system, these molecules are recognized by anti-MUC1 antibodies.1 However, due to these structures possessing the natural O-glycosidic linkage, these molecules are susceptible to degradation by endogenous glycosidases, leading to shorter half-lives.