Flow cytometry analysis was performed using NovoCyte 2060R (ACEA Biosciences, San Diego, CA, USA) according to previous report (17 (link)). The transduction efficiency of IM19 CAR gene into T cells was detected using a phycoerythrin (PE)-labeled anti-CAR antibody which was developed by Immunochina Pharmaceuticals for recognizing the scFv of IM19. PE-anti-CD4 and FITC-anti-CD8 antibodies (BD Biosciences, San Jose, CA, USA) were used to detect the CD4/CD8 ratio. The APC-anti-CD45RA and FITC-anti-CD62L antibodies (Biolegend, San Diego, CA, USA) were used to evaluate the ratio of memory T cells.