Twenty-five patients (61.0%) and seven patients (26.9%) developed severe infections within 30 days post-CAR T-cell infusion in the G-CSF group and non-G-CSF group, respectively, including 14 upper respiratory tract infections, 13 pneumonias, 5 bacteremias, 1 intestinal infection and 1 skin soft tissue infection according to the infection site. This evidence concerns the gene CSF3 and Recurrent upper respiratory tract infections.