ELIMINATION OF LEUKEMIC-CELLS FROM RAT BONE-MARROW USING ANTIBODY AND COMPLEMENT

Abstract

An animal model was developed that utilizes antibody and complement to eliminate a transplantable cloned line of Wistar/Furth acute nonlymphocytic leukemia (Cl-3) from syngeneic Wistar/Furth more bone marrow. The Cl-3 leukemia grows progressively from an i.v. inoculum of 101-102 cells. Antiserum was raised in rabbits following multiple injections of Cl-3. Using optimal concentrations of absorbed antibody and complement, .apprx. 103 tumor cells could be destroyed in vitro, judge by the number of cells required to produce progressive growth in vivo. Similar incubation with antibody and complement did not affect the ability of Wistar-Furth marrow to reconstitute rats that had received lethal total-body irradiation (950 R). Each of the 33 irradiated rats that received mixtures of 104 Cl-3 and 1.6 .times. 108 nucleated bone marrow cells succumbed to leukemia within 65 days; 16 of 33 rats (48%) receiving similar inocula that had been treated with antibody and complement survived > 180 days without evidence of tumor growth. Repeated treatment of contaminated marrow with antibody and complement following removal of mature granulocytes and erythrocytes on density gradients permitted elimination of 105 Cl-3.