Abstract: The invention is directed to a method for activating CAR cells having at least one chimeric antigen binding receptor in a sample by incubating the sample with at least one substrate provided on its surface with at least one anti-CAR idiotype antibody and/or at least one antigen selected from the group consisting of CD19, CD20, CD22, BCMA, CD33, MSLN, CD123, HER2, GD2, EGFR, PSMA, MUC1, CD318, TSPAN8, CD66c, CEA, CLA, CD276, FolR1, CLEC12A, CLL-1 and CD371, and with at least one costimulatory molecule selected from the group consisting of CD28, CD2, CD6, CD26, CD53 and LFA-1 characterized in that the sample is incubated with the at least substrate in suspension thereby activating the CAR T cells to express markers selected from the group consisting of mRNA, effector molecules or cell surface activation markers.

Abstract: The invention is directed to a Conjugate for labelling a target moiety on a cell, characterized by general formula (II): Xo-P-Ym, with Y: MHC-complex targeting TCR molecules, P: enzymatically degradable spacer, X: detection moiety, o: integer between 5 and 25, m: integer between 2 and 1000, wherein X and P; P and Y are covalently bound to each other and Y is bound to P via the C-terminus.