Three different acid phosphatase patterns in leukaemic lymphoid T-cells.

The acid phosphatase pattern was studied in leukaemic cells from 8 patients with T-cell leukaemia (5 ALL and 3 CLL). In 2 cases the enzyme activity was focal granular with paranuclear localization as earlier demonstrated by other authors, while--in contrast to these findings--the enzyme activity in 4 cases demonstrated universal granular distribution. Almost all the cells from each patient showed the same picture. In the last 2 cases a mixed focal and universal granular pattern was observed, where half the cells possessed the focal form and the other half the universal form of granular activity. The two first-mentioned patterns were observed in cases of T-ALL as well as of T-CLL, while the mixed pattern was seen only in cases of T-ALL.