It has been reported that after activation, CD28 co-stimulated CAR-T cells released higher levels of effector cytokines including IL-2, IFN-γ, and TNF-α, as compared to 4-1BB co-stimulated counterparts, however, conflicting data exist concerning this perception.25,26 HER2 is expressed on most solid tumors that are prone to form malignant effusion after pleural or peritoneal dissemination, including the lung, breast, gastric and ovarian cancers. Here, CD28 is linked to ovarian carcinoma.