A conjugate constituted by a monoclonal anti-Thy 1.2 antibody chemically coupled to the toxic subunit of ricin was synthesized. The conjugate was specifically cytotoxic for Thy 1.2+ (EL 4) but not for Thy 1.2− (BW5147) thymoma cells. In vitro treatment of bone marrow-leukemia cell mixtures (10:1 and 1:1 bone marrow to EL 4 cell ratios) with anti-Thy 1.2-ricin A chain totally eradicated EL 4 tumor cells, while the number of myeloid colony-forming units and pluripotent colony-forming units developed in vitro and in vivo was unaffected, which suggested that the treatment had no toxic side effects at least on the precursor cells examined.
ASJC Scopus subject areas
- Cancer Research