"PMN-elastase assay": enzyme immunoassay for human polymorphonuclear elastase complexed with alpha 1-proteinase inhibitor.

A solid phase, enzyme-linked immunoassay is described for the quantitative determination of the complex of human granulocyte elastase (EC 3.4.21.37) with alpha 1-proteinase inhibitor. The assay employs antibody-coated test tubes and it is suitable for routine use in clinical chemistry laboratories. Data for sample stability and test characteristics are given. A reference range of 20-180 micrograms/l elastase in plasma was determined. The diagnostic significance of granulocyte elastase levels in plasma in inflammatory diseases is discussed.

Purification of alpha 1-proteinase inhibitor by triazine dye affinity chromatography, ion-exchange chromatography and gel filtration on Fractogel TSK.

The purification of plasma proteins by affinity chromatography on triazine dye matrices can be optimised with regard to the triazine dye used as a group-specific ligand. A comparison by electrophoretic and immunological means of the results of affinity chromatography with human plasma on Fractogel TSK-Blue and Fractogel TSK-Red demonstrated that the Procion Red HE-3B-containing gel was able to adsorb more plasma constituents than the Cibacron Blue F3-GA gel. The preparation of alpha 1-proteinase inhibitor obtained after chromatography on Fractogel TSK-Red showed a higher degree of purity and could easily be further purified by ion-exchange chromatography on Fractogel TSK DEAE-650 and gel filtration on Fractogel TSK HW 55, without significant loss of biological activity.

Enzyme-linked immunoassay for human granulocyte elastase in complex with alpha 1-proteinase inhibitor.

Granulocyte elastase in complex with its main inhibitor in plasma, i.e. alpha 1-proteinase inhibitor, was quantitatively determined by incubating the sample with solid-phase fixed antibodies against elastase first and reacting then with alkaline phosphatase-labelled antibodies against alpha 1-proteinase inhibitor. In normal plasma a level of 97.5 +/- 25.8 micrograms elastase/1 (mean +/- s.d., n = 43) was found, whereas moderately to markedly increased plasma concentrations were demonstrated in a variety of patients with inflammatory diseases like septicemia or rheumatoid arthritis.

Quantitative determination of creatine kinase isoenzyme catalytic concentrations in serum using immunological methods.

For the determination of creatine kinase isoenzyme catalytic concentrations in serum two methods based on immunological reactions are presented: One method uses inhibiting antibodies, which selectively block the activity of creatine kinase M subunits ("Inhibition Test"). This test is used for routine measurements of creatine kinase MB catalytic concentration; Another method uses precipitating antibodies, which allows a quantitative differentiation of creatine kinase isoenzymes MM, MB and BB ("Precipitation Test"). This test is used as a control for the Inhibition Test for the possible presence of creatine kinase BB activities in doubtful cases. Procedures, specificity, correlation and application of these methods are discussed.

[Determination of creatine kinase-MB in serum using inhibiting antibodies (author's transl)]. / Bestimmung der Aktivität von Creatinkinase MB im Serum unter Verwendung inhibierender Antikörper

A new method for the determination of creatine kinase-MB activity in the serum is presented. The principle of this method is the direct measurement of the activity of creatine kinase M subunits by inhibiting antibodies. The total test procedure takes 15 min. In the sera of all the 83 patients tested, who have clinically proven myocard infarction, creatine kinase-MB activity can be measured between the 6th and 28th hour after infarction. At the time of maximum total creatine kinase activity the percentage of creatine kinase-MB activity is between 6 and 17%, the mean value being 8%. In cases of emergency this method can be used for the differential diagnosis of elevated total creatine kinase activities of unknown origin.

[Determination of creatine phosphokinase-MB in the serum of patients with myocardial infarction by an immunological method (author's transl)]. / Immunologischer Nachweis von Creatinkinase-MB im Serum beim Myokardinfarkt.

The immunological method of determining creatine phosphokinase-MB in the serum of patients with myocardial infarction described here is based on the differential measurements of CK-activities before and after a specific immuno-precipitation of the CK-MB type. The minimum activity of the CK-MB-type which it is possible to determine with this method is 4% of the total activity. In patients with clinically confirmed myocardial infarctions 1-15% (mean 7.8%) of the total activity can be calculated as CK-activity of the MB-type on the first/second day(s) after the infarction. In patients with increased total CK-activity and without verified infarction the CK-MB content does not differ significantly from zero. The differences between the two groups are statistically significant. In patients with myocardial reinfarction the CK-MB-activity is higher than that after the first infarction. The immunological method to determine creatine-phosphokinase isoenzyme MB is of differential-diagnostic value in myocardial infarction.