[Acid alpha-D-mannosidase of XXXX leukocytes in the norm and during @entity1860 ].

@entity1 @entity1778 @entity1860 @entity8851
The activity and properties of acid alpha-mannosidase were studied in normal granulocytes and in two types of myeloid cells from @entity1 with @entity1860 . The activity of the enzyme in @entity1778 cells was 2-fold higher than that in normal granulocytes and in morphologically matured myeloid cells. Two latter types of cells did not differ in alpha-mannosidase activity. Kinetic properties, thermo- and pH stability of alpha-mannosidase from normal and @entity1778 cells were similar. alpha-mannosidase in @entity1778 and normal cells existed in two forms (A and B), which were easily separated on @entity8851 -cellulose column. These two forms differed in molecular mass (300 and 290 kD, respectively) and in the degree of sialylation. The quantitative ratios of A and B forms in normal and @entity1778 cells were different. In normal granulocytes and in mature cells from @entity1 this ratio was 0.60 and 0.67, respectively. In @entity1778 cells the ratio was found to be 1.31. Thus, in @entity1778 cells form A of alpha-mannosidase predominanted, whereas in normal cells the predominance of form B was observed. It was suggested therefore that in @entity1778 cells the enhanced synthesis of alpha-mannosidase occurred in parallel with the accumulation of the B form. This accumulation was assumed as the cause of enhanced activity of the enzyme in immature @entity1778 cells.
