Determination of human XXXX -antithrombin III complex in plasma with an enzyme-linked immunosorbent assay.

@entity1 @entity1150 @entity556 @entity1151
An enzyme-linked immunosorbent assay (ELISA) was developed for the determination of @entity556 -antithrombin III complex (TAT) in @entity1 plasma. The test system follows the sandwich principle and uses two different antibodies directed against @entity1 @entity556 and human antithrombin III, respectively. The antibodies bind selectively to the corresponding antigen moieties of TAT. The assay was calibrated with definite concentrations of preformed purified TAT added to TAT-poor plasma. The lower limit of sensitivity of the assay was 0.5 microgram/l. Mean coefficients of variation of 4.2% (intraassay) and 3.5% (interassay) were found for TAT concentrations between 2 and 60 micrograms/l. A reference range from 0.85 to 3.2 micrograms/l was calculated from TAT concentration in plasma samples from 88 healthy donors (mean value +/- SD: 1.45 +/- 0.4 micrograms/l). In plasma samples from @entity1 with @entity1151 (n = 17), TAT concentrations between 3 and 25 micrograms/l were measured. In 15 @entity1 with @entity1150 , TAT was found up to 3 to 25 micrograms/l. From these data we conclude that measurement of TAT can be a sensitive parameter for specific detection of a latent activation of the clotting pathway.
