IMPROVED GROWTH OF INVITRO COLONIES IN HUMAN ACUTE-LEUKEMIA WITH FEEDING CULTURE METHOD

Abstract

Bone marrow cells freshly aspirated from 10 untreated adult patients with acute nonlymphocytic leukemia were cultured by 2 methods: the conventional agar culture method for myeloid colony formation and its modification by daily feeding with culture medium. In 5 patients, colonies grew in higher numbers (4.7- to 330-fold) with feeding than without. Three patients grew colonies only with feeding. Two of these 3 patients required L-ascorbic acid in the fed medium for colony growth. Colonies did not grow from the remaining 2 patients by any method. In 7 patients the number of colonies grown with feeding was up to 170 times higher, than those from normal control marrows, which grew the same number of colonies regardless of feeding or L-ascorbic acid. Peroxidase and Wright''s stains indicated the myeloid differentiation of the cells in the leukemic marrow colonies. The leukemic origin of the colonies was proven by chromosomal analysis. The wide range of linearity between the number of cells plated and the number of colonies grown permits quantitative assay of colony-forming leukemic cells. This assay should be valuable for studies of chemotherapy, growth regulation and differentiation of leukemic cells.