Effecters on human placental alkaline phosphatase activity

1993 ◽  
Vol 31 (2) ◽  
pp. 145-151 ◽  
Author(s):  
M. G. Roig ◽  
N. I. Ghaïs ◽  
F. J. Burguillo ◽  
J. M. Cachaza ◽  
J. F. Kennedy
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Placental Alkaline Phosphatase ◽  
Human Placental Alkaline Phosphatase

Macromolecular alkaline phosphatase and an immunoglobulin G that inhibited alkaline phosphatase in a patient's serum.

1983 ◽  
Vol 29 (2) ◽  
pp. 375-378 ◽  
Author(s):  
H Nakagawa ◽  
K Umeki ◽  
K Yamanaka ◽  
N Kida ◽  
S Ohtaki
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Immunoglobulin G ◽  
Significant Loss ◽  
Placental Alkaline Phosphatase ◽  
Type Ii ◽  
Intestinal Alkaline Phosphatase ◽  
Adult Type ◽  
Heat Stable

Abstract Macromolecular alkaline phosphatase (EC 3.1.3.1) was found in the serum of a patient suffering from myasthenia gravis (adult type II) complicated with thymoma, and was shown by immunoelectrophoresis to be bound to immunoglobulins A and G (IgG). Placental alkaline phosphatase, complexed with either the patient's serum or IgG purified from the patient's serum, remained at the origin on electrophoresis, with significant loss of activity. Intestinal alkaline phosphatase, complexed with either the patient's serum or the patient's IgG, migrated to a position similar to that of the macromolecular alkaline phosphatase in the patient's serum on electrophoresis. About 50% of the placental alkaline phosphatase activity was inhibited with 0.1-0.2 g of the patient's IgG per liter, but 6.93 g of the IgG per liter was required for about 20% inhibition of the intestinal alkaline phosphatase activity. The complex of intestinal alkaline phosphatase with the patient's IgG was fairly heat stable. From these results, we concluded that the macromolecular alkaline phosphatase in the patient's serum consisted of intestinal alkaline phosphatase and IgG that was specific for placental alkaline phosphatase.

scholarly journals Isolation and characterization of a Chinese hamster ovary (CHO) mutant defective in the second step of glycosylphosphatidylinositol biosynthesis

1996 ◽  
Vol 313 (1) ◽  
pp. 253-258 ◽  
Author(s):  
Victoria L. STEVENS ◽  
Hui ZHANG ◽  
Michelle HARREMAN
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Chinese Hamster Ovary ◽  
Chinese Hamster Ovary Cells ◽  
Chinese Hamster ◽  
Second Step ◽  
Molecular Defect ◽  
Placental Alkaline Phosphatase ◽  
Isolation And Characterization

Mutant cell lines defective in the biosynthesis of glycosylphosphatidylinositol (GPI) described to date were isolated by selecting cells which no longer expressed one or more endogenous GPI-anchored proteins on their surface. In this study, a new mutant in this pathway was isolated from ethylmethanesulphonate-mutagenized Chinese hamster ovary cells stably transfected with human placental alkaline phosphatase (PLAP) as a marker of GPI-anchored proteins. A three-step protocol was employed. In the first step, cells with decreased surface expression of PLAP were selected by four rounds of complement-mediated lysis with an anti-(alkaline phosphatase) antibody. The surviving cells were cloned by limiting dilution and those with low levels of total alkaline phosphatase activity were selected in the second step. Finally, the ability of each clone to synthesize the first three intermediates in GPI biosynthesis in vitro was assessed to determine which cells with low alkaline phosphatase activity harboured a defect in one of these reactions. Of 230 potential mutants, one was defective in the second step of GPI biosynthesis. Microsomes from this mutant, designated G9PLAP.85, were completely unable to deacetylate either endogenous GlcNAc-phosphatidylinositol (PI) synthesized from UDP[6-3H]GlcNAc or exogenous GlcNAc-PI added directly to the membranes. Complementation analysis with the Thy-1-deficient murine lymphoma cells demonstrated that G9PLAP.85 has a molecular defect distinct from these previously described mutants. Therefore, these results suggest that mutants in GPI biosynthesis could be selected from almost any cell line expressing a GPI-anchored marker protein.

Two new methods for separating and quantifying bone and liver alkaline phosphatase isoenzymes in plasma.

1984 ◽  
Vol 30 (7) ◽  
pp. 1182-1186 ◽  
Author(s):  
S B Rosalki ◽  
A Y Foo
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Wheat Germ ◽  
Placental Alkaline Phosphatase ◽  
Diagnostic Laboratory ◽  
New Methods ◽  
Cellulose Acetate Membranes ◽  
Wheat Germ Lectin ◽  
Liver Fraction

Abstract We describe two new methods for the separation and quantification of the bone and liver isoenzymes of alkaline phosphatase (EC 3.1.3.1) in plasma. In the first, we use wheat-germ lectin to precipitate the bone isoenzyme. About 80% of this, but minimal liver isoenzyme, is precipitated. The activity of the bone isoenzyme is calculated from measuring the alkaline phosphatase activity in the precipitate, that of liver alkaline phosphatase by subtracting the activity of the bone isoenzyme from total alkaline phosphatase activity. The liver fraction will also contain biliary, intestinal, and placental alkaline phosphatase if these are present in the original plasma, but correction for such activity is readily made. In the second method, samples are separated on cellulose acetate membranes that, before electrophoresis, have been soaked in buffer containing wheat-germ lectin. The bone isoenzyme is retarded and clearly separated from the liver fraction, allowing these isoenzymes to be quantified by densitometry. Both methods are rapid, reproducible, and suitable for use in the diagnostic laboratory.

Improved method for quantitative determination in serum of alkaline phosphatase of skeletal origin.

1981 ◽  
Vol 27 (12) ◽  
pp. 2002-2007 ◽  
Author(s):  
J R Farley ◽  
C H Chesnut ◽  
D J Baylink
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Serum Alkaline Phosphatase ◽  
Total Serum ◽  
Placental Alkaline Phosphatase ◽  
Serum Alkaline Phosphatase Activity ◽  
Total Body Calcium ◽  
Post Menopausal ◽  
Skeletal Alkaline Phosphatase

Abstract In this quantitative method for detection of skeletal alkaline phosphatase (EC 3.1.3.1) activity in human serum, intestinal and placental alkaline phosphatase activities are recognized by their susceptibility to inhibition by L-phenylalanine, and skeletal and hepatic alkaline phosphatases are distinguished by their different sensitivities to inactivation by heat. Alkaline phosphatase isoenzymes prepared from organ sources may behave differently from the corresponding isoenzymes in serum. Our procedure allows us to include organ-derived internal standards of skeletal, intestinal, and biliary alkaline phosphatase to minimize between-assay variation. In preliminary applications, we have found that (a) total serum alkaline phosphatase activity is extremely variable in post-menopausal osteoporotic subjects and is not a reliable index of skeletal alkaline phosphatase activity; (b) seven osteoporotic patients responding to therapy with sodium fluoride with increased bone formation showed increased skeletal alkaline phosphatase activity in their serum as compared with age-matched controls (p less than 0.005); and (c) 10 post-menopausal osteoporotic patients responding to therapy with stanozolol with increased total body calcium showed an increase in circulating skeletal alkaline phosphatase activity (p less than 0.001).

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