An Accelerated Red-Cell Hemagglutination Inhibition Immunoassay for Measuring Fibrinogen Degradation Products in Human Serum

Summary

A further modification of Merskey’s hemagglutination inhibition assay for measurement of fibrinogen degradation products (FDP) in human serum was developed. Blood is clotted in the presence of protamine chloride (25 u/ml), in addition to thrombin and s-aminocaproic acid, and at room temperature. Defibrination is complete within 5 min even in blood obtained from patients on heparin treatment. The hemagglutination immunoassay was also considerably accelerated by immediate addition of sensitized red cells to the mixtures of antiserum and antigen dilutions at 37° C. Accurate readings of FDP titers may thus be obtained within 20 min following venipuncture.

^* Address requests for reprints to: Prof. E. A. Beck, Hamatologisches Zentrallabor, Inselspital, CH-3008 Bern, Switzerland.

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