Cloning and characterization of bone marrow cells from patients with acute lymphoid leukemia (ALL) in agar cultures

Acute lymphoid leukemias (ALL) represent malignant clonal expansions of lymphoid hemopoietic cells arrested at different stages of B- or T-cell maturation. We studied surface marker profiles and cloning capability of bone marrow (BM) cells from 22 adult ALL-patients at diagnosis (n = 15) or relapse (n = 7) in agar cultures under different culture conditions in order to develop a screening system for the classification of ALL and the detection of residual leukemia. Immunophenotyping of those 22 BM-samples enabled a classification in B- or T-linear ALL. Colony growth of BM-cells could be obtained in four out of 20 cases of ALL at diagnosis and in one case at relapse. Different stimulating factors and their combinations (GM-CSF; IL-1; IL-2; IL-3; IL-4; IL-6; placenta conditioned media (PCM); Phytohemagglutinin (PHA, 40%) and lipopolisaccaride (LPS, 1.25%)--containing conditioned media ('B-ly'); IL-1+IL-3; IL-1+IL-4; IL-1+IL-6; IL-1+B-ly) did not show an overall significant difference in stimulating ALL-clones. Immunological phenotyping of ALL-clones in these 5 cases could prove the lymphoid leukemic character of the clones obtained.

Our data show that colony growth of ALL-BM-cells is difficult. Nevertheless, in cases where colony growth could be obtained those clones showed the original surface marker profile of the leukemic cells proving the specificity of our colony assay.