To measure the extent of leukocyte activation we offer the following assays:
Beta-Glucuronidase is one of the granule constituents of polymorphonuclear leucocytes, which remains free in circulation after release. Plasma levels of this enzyme can be quantified via a chromogenic assay. The rate of substrate conversion is directly proportional to the concentration of enzyme present. Enzymatic activity is expressed in mU/mL.
Polymorphic nuclear (PMN) granulocytes play an important role as primary defense cells in the human body. Different mediators (e.g. cytokines, leukotrienes, activated complement factors, bacterial endotoxins, activated clotting factors and fibrinolytic factors) attract and stimulate these cells. Activated PMN granulocytes release elastase, both by degranulation and by neo-formation, and therefore elastase can be used as a marker for leukocyte activation.
Free in plasma, elastase is rapidly neutralized by a1-proteinase inhibitor (a1-PI) to form a stable complex. PMN elastase/a1-PI complexes are quantified by a sandwich ELISA. The concentration of the PMN elastase/a1-PI complex is used as a measure of PMN granulocyte activation.
Myeloperoxidase is another enzyme abundantly expressed in neuthrophils. Upon activation of the neuthrophils MPO is secreted and can be measured in plasma as marker for leukocyte activation.