New enzyme immunoassay of fibrin- XXXX degradation products in plasma using a monoclonal antibody.

@entity4568 @entity1 @entity2002 @entity43 @entity19 @entity5642
In several diseases, such as disseminated @entity5642 , fibrin- @entity2002 degradation products ( @entity4568 ) can be detected when serum is used. To avoid the use of serum with the risk of falsely positive and negative results, and to quantitatively measure routinely low levels of @entity4568 in plasma, we developed a solid-phase enzyme immunoassay (EIA), using a monoclonal antibody (No. @entity4568 -14). It reacts specifically with @entity4568 , but not with the parent @entity2002 -fibrin molecule. To raise the monoclonal antibodies we injected into @entity19 a whole mixture of fibrin degradation products isolated after complete lysis of a @entity1 blood clot by tissue-type plasminogen activator, because there is a chance that such products resemble @entity4568 in @entity1 ' blood more closely than antigens derived from purified @entity2002 . The EIA developed is a two-step assay ("cap-tag procedure"), in which the monoclonal antibody is attached to the wells of microtiter plates. The monoclonal antibody is specific for a neoantigenic determinant in the fragment E moiety, exposed after degradation of @entity2002 -fibrin by plasmin. The assay discriminates neither between degradation products of @entity2002 and fibrin nor between fibrin degradation products that are or are not cross-linked. It is not disturbed by the presence of @entity2002 or fibrin monomer in plasma. The assay is accurate above 60 ng @entity4568 per milliliter and has a detection limit down to approximately 10 ng @entity4568 per milliliter when the supernatant of a lysed blood clot is used as calibration material. In frozen, then thawed plasma specimens from normal individuals, @entity4568 values varied between 30 and 110 ng/ml. Plasma of @entity1 with disseminated @entity5642 and of @entity1 receiving thrombolytic therapy had increased @entity4568 values. In @entity1 with @entity43 , @entity4568 concentrations in plasma varied with the clinical course of the disease. Results indicate that the EIA for @entity4568 in plasma is promising as a diagnostic tool in different clinical situations.
