Morphological, immunophenotypical and isoenzymatic profiles of human leukemia cells and derived T‐cell lines

Abstract

Six monoclonal leukemia cell lines (MOLT 12‐17) were established from three patients with acute leukemia. Two of the patients' samples were of the T‐ALL type, the third had morphological, isoenzymatic and immunological features of AMoL. The cell lines resulting from these original cells displayed distinct, but stable marker profiles. A comparison between primary cells and resulting cell lines showed that the cell lines established from patients with T‐ALL (MOLT 12, 13, 14 and MOLT 16, 17) expressed similar phenotypes and isoenzyme patterns, but were different in a few specific aspects. The changes suggest a modulation of marker expression in vitro or an arrest at a more immature stage of differentiation than the original cells. The cell line MOLT 15 established from the case of AMoL exhibited a quite discordant profile when compared to the primary sample: the cells lacked all previously found myelomonocytic antigens and a monocyte‐specific esterase isoenzyme, but expressed the T‐cell associated CD7 antigen and had rearrangements and RNA transcripts of the T‐cell receptor β and γ chain genes. This striking discrepancy between the patient's malignant cells and the corresponding cell line suggests that subpopulation selection had occurred in culture.