Liver- and Placenta-Like Alkaline Phosphatases (EC 3.1.3.1) Isoenzymes in Normal Human Neutrophils

Abstract

Alkaline phosphatase (AP) has been characterized in the neutrophil polymorphonuclear leukocytes (PMN) from 14 healthy adults. The biochemical properties of the isoenzymes were analyzed by the following methods: enzyme assays, slab gel electrophoresis, thermostability, inhibition pattern using four chemical inhibitors, and immunological specificity. In normal PMNs, two types of AP have been found: a thermolabile isoenzyme identical to the liver/bone/kidney type and a thermostable isoenzyme with respect to its electrophoretic properties, its level of thermostability, its immunological specificity, the thermostable isoenzyme resembles the placental form more closely than the intestinal form. These results are consistent with the proposal that granulocyte AP is a heterogeneous enzyme. Two enzyme forms appear to be expressed in this blood cell.

Changes in Neutrophil Alkaline Phosphatase Patterns in a Case of Chronic Myelomonocytic Leukemia

“…The main features revealed in the patient's NAP show a distinct difference from those of the normal enzyme [13]. In the case reported here, it appears as a shift in the heterogeneity of the component of NAP.…”

“…Conversely, in heated fractions, the results observed with the inhibitors used give val ues roughly similar to those of placental ALP, al though with more pronounced sensitivity to leucine. As for immunochemical behavior of NAP, reactivity with antiplacental ALP antibodies is very reduced; the antiliver isoenzyme antibodies show a stronger reaction, which however does not overlap that of the normal liver isoenzyme usually found in normal granulocytes [13]. Biochemical and histochemical as says of NAP in this case of chronic myelomonocytic leukemia demonstrate a high rate of specific enzyme activity.…”

“…Polymorphonuclear leukocyte preparation and biochemical methods (cell separation, enzyme activity, heat stability studies, en zyme kinetics with inhibitors, use of specific antibodies against ALP isoenzymes, electrophoresis) have been reported in a previous work [13].…”

An Enzymatic Marker in Mothers of Trisomy 21 Children: Neutrophil Alkaline Phosphatase

“…The procedure of cell sepa ration has been previously reported [10]. The contam inating nonneutrophil leukocytes were estimated.…”

“…The methods have been reported in a previous paper [10]. After cell sonication, an antiproteolytic agent, 1 mmol/1 phenylmethylsulfonyl fluoride, was added to the homogenate.…”