Lactate dehydrogenase isoenzymes in normal and malignant human lymphoid cells

Intracellular lactate dehydrogenase (LD) isoenzyme patterns were studied in the malignant cells of patients with a variety of lymphoid malignancies. These were compared with intracellular LD isoenzyme patterns of normal lymphoid cells and were also correlated with immunologic cell surface marker characteristics. Results showed that, in general, the malignant B cells of Burkitt's lymphoma and the lymphoblasts of T-cell acute lymphoblastic leukemia had isoenzyme patterns similar to those of normal B and T cells, respectively. The isoenzyme patterns of malignant lymphoid cells from patients with non-T, and non-B acute lymphoblastic leukemia, cutaneous T-cell lymphoma, and chronic lymphocytic leukemia were more heterogeneous. These data, although based on small numbers of patients, are consistent with the hypothesis that LD isoenzymes may reflect differences in the maturational status of cells within a single diagnostic category.