EVIDENCE FOR DIFFERENTIATION OF HUMAN LEUKEMIC BLOOD-CELLS IN DIFFUSION CHAMBER CULTURE

Abstract

Peripheral blood cells of 21 patients with different forms of acute leukemia were cultured in diffusion chambers (5 .times. 105 cells/chamber) implanted i.p. in 650 R preirradiated host mice over a period of up to 21 days. In patients with acute myeloid leukemia (AML), acute erythroleukemia (AEL) or acute myelomonocytic leukemia (AMMoL), the total number of cells which developed during this culture period exceeded the implanted value and also the values for normal peripheral blood cells from 10 controls. In acute undifferentiated leukemia (AUL), 2 of 6 patients showed considerable growth whereas the others, and also 2 patients with acute lymphoid leukemia (ALL), had poor growth. Differential counts revealed that the rise in total cells was due to proliferation of blast cells and formation of granulopoietic cells. The latter exceeded the numbers from normal peripheral blood cells in 9 of 13 patients with AML, AEL or AMMoL and in 2 of 6 patients with AUL, but not in the 2 patients with ALL. The production of granulopoiesis was not restricted to proliferating cells, but included mature cells which were of abnormal morphology in some cases. From the amount of granulopoiesis and the time of its development it was assumed that they were at least partly derived from leukemic blast cells. Chromosome analyses to decide whether the granulopoietic cells were of leukemic or normal cell origin are in progress.