Fang et al. first report that patients with advanced refractory ovarian cancer who received autologous PD-1-meso CAR-T cells (secreting full-length PD-1 antibodies) treatment have expanded CAR-T cell numbers in the bloodstream, and their own CD8+ T cell activity is also significantly enhanced, indicating that CAR-T cells infused back into the human body can mobilize immune cells to target tumor cells efficiently and precisely, rapidly improving the tumor local microenvironment’s immune function to kill cancer cells without causing significant adverse reactions [440]. Here, PDCD1 is linked to cancer.