TFRC and brain neoplasm: The in vitro and in vivo efficacy of two such targeted protein toxins was studied: (1) Tf-CRM107, a conjugate of human TR and full-length DT with two point mutations in the B chain with reduced toxin binding (CRM107) [56], and (2) 454A12-rRA, a conjugate of a mAb (454A12) to the human TR and recombinant ricin A chain (rRA), against TR-expressing brain tumors.