Toxicologic and marrow transplantation studies in rhesus monkeys given dimethyl myleran

The hematologic and pathologic effects of single doses of dimethyl myleran (DMM) were evaluated in rhesus monkeys with and without the infusion of marrow. DMM 3 to 5 mg/kg produced severe but reversible myelotoxicity and no non-marrow toxicity. All animals given DMM 10 mg/kg died of marrow failure which was consistently reversed by the infusion of cryopreserved autologous marrow. At higher doses of DMM the protective effect of autologous marrow was less consistent due to increased gastrointestinal toxicity. Allogeneic engraftment was not achieved following administration of 10 mg/kg of DMM. In two animals receiving 15 mg/kg, proliferating allogeneic donor cells were present in recipient marrow seven days after marrow infusion.