The IC50 values determined in the MTT assay was 18 ± 3 pM, 21 ± 3 pM, and 27 ± 13 pM for CHO CFPS-produced RIT and 86 ± 30 pM, 116 ± 40 pM, and 52 ± 10 pM for E. coli CFPS-produced RIT on CD7-positive Jurkat, HSB-2, and ALL-SIL cells, respectively. The gene discussed is CD7; the disease is acute lymphoblastic leukemia.