title: Development of a radioimmunoassay for [DES-ARG9]-bradykinin.
abstract: Antisera to [des-Arg9]-bradykinin were elicited in rabbits immunized with the peptide conjugated to thyroglobulin and/or ovalbumin. Sera were screened for the presence of antibody with three radioactive antigens, mono-125I-labeled derivatives of [Tyr1, des-Arg]-kallidin, [Tyr, des-Arg]-bradykinin, and [Tyr, des-Arg]-bradykinin that were prepared by treating mono-125I-labeled [Tyr]-kallidin, [Tyr]-bradykinin, and [Tyr]-bradykinin with carboxypeptidase B. Of the six animals immunized, five produced antibodies to [des-Arg]-bradykinin as evidenced by the ability of their sera to bind at least 33% of the added radioactivity at a final dilution of 1:500. Sensitivity and specificity studies were performed with each labeled antigen and a dilution of antiserum that bound 30-50% of the radioactivity. The best labeled antigen-antibody combination, with respect to titer, sensitivity, and specificity was obtained with [mono-125I-Tyr, des Arg]-bradykinin and serum from a rabbit immunized with [des-Arg]-bradykinin conjugated to ovalbumin with toluene diisocyanate. The lowest concentration of [des-Arg]-bradykinin inhibiting 50% of this radioactive antigen binding was 0.23 ng/ml and the lowest concentration which could be distinguished from no [des-Arg]-bradykinin added was 67 pg/ml. This antiserum cross-reacts with bradykinin and lysyl-bradykinin about 9% but not with methionyl-lysyl-bradykinin.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D001920:Bradykinin / Q000031:analogs & derivatives* / Q000097:blood; D043424:Carboxypeptidase B; D002268:Carboxypeptidases / Q000494:pharmacology; D005260:Female; D007705:Kinins / Q000378:metabolism; D008297:Male; D011817:Rabbits / Q000276:immunology; D011863:Radioimmunoassay
chemical_list: D007705:Kinins; C024626:bradykinin, des-Arg(9)-; D002268:Carboxypeptidases; D043424:Carboxypeptidase B; D001920:Bradykinin