A test for determining the anti-coagulation level in blood samples is based on ascertaining the presence of heparin-antithrombin-III complex therein. This may be done with the aid of antibodies against thrombin-antithrombin-III complex, such antibodies being used e.g. in the form of a latex reagent or a bloodcell reagent.
Disclosed herein are assays for measuring the amount of heparin present in a biological sample. The assays use a positively charged polycarbodiimide heparin-inhibitor compound and antibodies which recognize heparin when bound to the carbodiimide inhibitor but do not react with free heparin.
This invention pertains to a method of detecting, in a sample obtained from an individual, anti-heparin antibodies which inhibit the formation of the heparin accelerated antithrombin III-thrombin complex. In the present method, the presence of such anti-heparin antibodies are detected directly (by detecting the presence of anti-heparin antibodies themselves) or indirectly (by detecting the presence or formation of the heparin accelerated antithrombin III-thrombin complex). In one embodiment of the present method, antibodies which react with or interfere with the heparin pentasaccharide which binds antithrombin III in such a manner that binding to antithrombin III is inhibited are detected. In a specific embodiment of the present method, the anti-heparin antibody detected is one which reacts with or interferes with the disaccharide UA-2S/GlcNs-6 present in residues IV and V of the heparin pentasaccharide that binds antithrombin III.
A reagent for determination of human blood coagulation factor XIII for reversed passive hemagglutination reaction which comprises sensitized erythrocytes prepared by sensitizing animal erythrocytes with specific anti-human factor XIII antibody, and a kit using the reagent are disclosed.
A new and useful method for assaying proteases, in which an excess of tagged proteinaceous inhibitor of a protease is mixed in solution with a sample containing the protease to form a mixture of a tagged inhibitor-protease complex and free tagged inhibitor. The complex is separated from the tagged inhibitor and the tag measured. Alternatively, anti-protease antibody may be added to bind the complex so that assay specificity and/or separation is enhanced. The method of this invention is applicable to assaying minute quantities of clinically significant proteases e.g. renin, kallikrein, thrombin occurring in serum, plasma, urine and other tissues.
A low ionic strength suspending medium for immunologic reactions which includes a salt solution, a buffer, gelatin, albumin, and an organic solute to control osmolality.
