Isoenzyme studies in human leukemia-lymphoma cell lines--V. Induction of differentiation by T-cell derived...

A panel of human leukemia cell lines from various lineages (T-cell, pre B- and Non-T/Non-B cell, myelomonocytic and erythroleukemia cell lines) were utilised as model systems of the distant effects of differentiation-inducing activity (DIA) produced by the T-leukemia cell line HUT-102. DIA inhibited cell proliferation and induced distinct morphological changes which were more pronounced in the myelomonocytic and erythroleukemia cell lines than in the lymphoid cell lines. DIA triggered in the myelomonocytic and erythroleukemia cell lines an increase in the number of NBT-reducing cells and caused strong adherence to plastic surface. The T-cell lines showed aggregation of cells in floating clusters. In the isoenzyme analysis of the enzymes carboxylic esterase and acid phosphatase, it was found that DIA stimulated the new expression of isoenzymes and a stronger staining intensity of several isoenzyme bands in all cell lines, however, at varying degrees. HL-60 and HEL displayed newly a monocyte-specific isoenzyme. Several myelomonocytic and erythroleukemia cell lines were triggered to express the tartrate-resistant acid phosphatase isoenzyme. The cell kinetic, morphological, functional and isoenzymatic data demonstrated that DIA effected the development of the different blood cell types. However, it appears that the cells reached a new differentiation block after acquired expression of differentiation-linked features; the lymphoid cell lines were more limited in their response to DIA than the myeloid and erythroid cells.