Enzyme polymorphism in the classification of human malignant lymphoma.

Recent studies on the polymorphism of lysosomal hydrolases have shown that all individual blood cell types in the human being possess their own isoenzyme pattern. In the present study acid phosphatase activity of normal human B-lymphocytes and of four different types of low-grade malignant non-Hodgkin's lymphomas according to the Kiel classification was estimated. In addition, the isoenzyme pattern of AcP was investigated by isoelectric focusing. Chronic lymphocytic leukemia of B-cell type (N = 9) and centroblastic centrocytic follicular lymphoma (N = 10) demonstrated significantly lower values than lymphoplasmacytic/lymphoplasmacytoid lymphomas (N = 28) and plasmacytomas (N = 8). The isoenzyme pattern of normal human B-lymphocytes comprised 12 bands between pH 6.3 and 3.85. This basical pattern was shared by all four lymphoma entities. Only lymphoplasmatic lymphoplasmacytoid lymphoma and plasmacytoma revealed additional bands, which probably account for the higher net enzyme activity in these cases.