Summary
We have developed a two-step enzyme immunoassay (EIA) that allows the quantitation
of degradation products derived from fibrinogen (FbgDP) and that does not detect degradation
products derived from cross-finked (XDP) or noncrosslinked fibrin (fdp).
The EIA is based on two monoclonal antibodies (FDP-14 and Y-18), developed in our
institute. FDP-14 is used as catching antibody. It complexes exclusively with degradation
products, irrespective whether these are derived from fibrinogen or from fibrin. It
does not complex with intact fibrinogen or fibrin. Y-18 is reactive with fibrinogen
and fibrinopeptide A-comprising fibrinogen fragments. It is used, conjugated with
horse-radish peroxy-dase, as tagging antibody.
The FbgDP-EIA is highly specific, accurate and sensitive. The coefficient of variation
is between 3 and 8%; the lower detection limit is less than 0.025 μg/ml.
The assay has been applied to plasma from patients with suspected disseminated intravascular
coagulation (DIC), to plasma from patients undergoing streptokinase (SK) therapy for
acute myocardial infarction and to plasma from newborn babies.
DIC patients had no or very low levels of FbgDP, but high levels of other degradation
products, SK-treated patients showed high levels of degradation products two hours
after termination of the SK infusion. A considerable fraction of these degradation
products was shown to be FbgDP. Plasma from newborn babies contained elevated levels
of FbgDP associated with prolonged prothrombin times.
Keywords
Enzyme immunoassay - Primary fibrinogenolysis - Monoclonal antibodies - Fibrinogen
degradation
