The invention belongs to the technical field of
cellular immunotherapy, and particularly relates to a PD-1
gene knockout MUC1-targeting CAR-
T cell as well as a preparation method and application thereof. An MUC1-targeting
chimeric antigen receptor is prepared firstly, wherein the MUC1-targeting
chimeric antigen receptor comprises an
antigen binding structural domain, a transmembrane structural domain, a co-stimulation structural domain and an
intracellular signal transduction structural domain. Tn
glycosylation MUC1 is used as a target spot, the target spot specificity is high, off-target is not likely to occur, and the safety of the CAR-T cells is improved. On the basis, the PD-1
gene knockout MUC1-targeting CAR-
T cell is obtained, and after the PD-1
gene is knocked out and the CAR-
T cell is transfused back into a body, the CAR-T
cell failure and inactivation caused by PD-L1 expressed by tumors cannot occur, so that the efficient specific
cell killing effect on
tumor cells is achieved, and the
curative effect of the CAR-T
cell is improved.