Immunochemical studies of antisera to human fibrinopeptide-B
VP Butler , DA Weber, HL Nossel, D Tse-Eng, KS LaGamma and RE Canfield
The immunochemical specificity of rabbit antisera to human fibrinopeptide-B
(FPB) has been studied by comparing the relative abilities of FPB and of
various proteins and peptides containing the NH2-terminal segment of the B
beta-chain of human fibrinogen to inhibit the binding of a radioiodinated
FPB derivative by each of seven anti- FPB sera. Anti-FBP sera varied in the
extent to which they cross- reacted with fibrinogen, the NH2-terminal
disulfide knot of fibrinogen (N-DSK), B beta 1(Pyr)-118(Met), B beta
1(Pyr)-42(Arg), and desarginyl- FPB. Anti-FPB sera have been identified
that discriminate effectively between FPB and larger FBP-containing
peptides; such antisera can be used to measure FPB in the absence of the
larger peptides or to demonstrate the presence of larger peptides such as B
beta 1(Pyr)- 42(Arg) in extracts of clinical plasma samples by means of an
increase in FPB immunoreactivity following thrombin treatment. One anti-FPB
serum has been identified that is capable of detecting desarginyl-FPB, and
this antiserum has been used in the development of a radioimmunoassay for
desarginyl-FPB. Thus, by precisely defining the specificity of anti-FPB
sera, it has been possible to identify antisera that are useful, not only
in the measurement of FPB, but also in the detection of other important
related molecules, such as B beta 1(Pyr)- 42(Arg) and desarginyl-FPB. The
immunochemical detection of these FPB- related peptides should provide
useful information concerning the action of proteolytic enzymes, such as
plasmin on the NH2-terminal segment of the B beta-chain of fibrinogen, and
of carboxypeptidase-B on free FPB, in human plasma.
Volume 59,
Issue 5,
pp. 1006-1012,
05/01/1982
Copyright © 1982 by The American Society of Hematology
