Macroenzymes and their clinical significance.

Macroenzymes are serum enzymes that have higher molecular mass than the corresponding enzyme normally found in serum under physiologic or pathophysiologic conditions. They are formed either by self-polymerization or by association with other serum components. Because they are cleared much more slowly than the usual enzymes, macroenzymes accumulate in the plasma and thus cause an increase in the activity of the corresponding enzyme in blood samples. Biochemically macroenzymes can be classified into two groups (macroenzymes type 1 and type 2). The importance of macroenzymes in this time is mainly in the possibility of misinterpretation of blood plasma enzyme activities. Macroenzymes are interesting also because of their association with several diseases and are being investigated as possible diagnostic markers. (Tab. 2, Ref. 20.).