Characterisation of a Soluble High Molecular Weight e Fragment Released by Plasmin from Cross-linked Fibrin

The heterogeneity of fragments released by plasmin degradation of cross-linked human fibrin has been examined. Six components (labelled 1–6) have been detected by PA gel electrophoresis and the two components (3 and 4) that make up the D dimer complex have been examined in relation to fragments D and E. Using two dimension Immunoelectrophoresis (with PA gel in the first dimension) and immunodiffusion, together with SDS PA gel electrophoresis of the fragments and their subunits, it has been shown that the more anodic component (band 4) of the complex is D dimer. Band 3, which is the recently reported high MW component (Gaffney et al., Clin. Sci. Mol. Med., in press) that reacts with antisera to fragments D and E, is shown to be a strong non-covalent association of D dimer and E. This observed heterogeneity of the components of fibrin digestion is significantly more complex than has been previously reported.