Elsevier

Thrombosis Research

Volume 12, Issue 4, April 1978, Pages 653-665
Thrombosis Research

Comparative immunochemical characterization of products of plasmin and leukocyte protease cleavage of human fibrinogen

https://doi.org/10.1016/0049-3848(78)90255-4Get rights and content

Abstract

Plasmin-dependent as well as a plasmin-independent alternative pathways for fibrinolysis have been recognized, but means of discriminating between the products of these two pathways have not been established. To this end, a major product of the cleavage of human fibrinogen by neutral leukocyte proteases, a 270,000 MW derivative designated Fragment I, has been immunochemically compared with the D:E complex produced by plasmic cleavage. Both classes of cleavage fragments exhibited absolute antigenic deficiency relative to native fibrinogen. Differences in the expression of residual native fibrinogen determinants were distinctive and localized to both the D and the E domains of the molecule; quantitative differences were predominantly localized to the D domain, whereas differences in competitive inhibition slopes were restricted to the E domain. The cleavage-associated neoantigens, fg-Dneo and fg-Eneo, were expressed differently by the two types of cleavage products. In contrast to the complete expression of fg-Eneo by the plasmic D:E complex, this neoantigen was minimally expressed by Fragment I but somewhat comparable to that of plasmic fragment X. Fragment I was clearly distinguishable from the plasmic cleavage products with respect to the expression of fg-Dneo. The competitive inhibition slopes differed, and Fragment I was antigenically incomplete for fg-Dneo. It is concluded that the cleavage products of fibrinogen generated by neutral leukocyte proteases and by plasmin are immunochemically distinguishable; and assays for fg-Dneo may provide a means for discrimination of the pathways of fibrinolysis mediated by these enzymes.

References (21)

There are more references available in the full text version of this article.

Cited by (8)

View all citing articles on Scopus
View full text