Determination of human plasma kininogen by a single radial immunodiffusion method and the bradykinin equivalent.
An SRI method is presented for the quantitation of native human plasma kininogen using a monospecific high avidity antiserum prepared against the conformational determinants of kininogen heavy chain (HC antigen). The SRI value of total human plasma kininogen averaged 0.260 +/- 0.052 g/l (+/- 2 SD) using a standard curve of normal human plasma in each assay (measuring range 0.016-0.260 g/l). The SRI data, confirmed by RIA, were compared with determination of the bradykinin equivalent by bioassay 4.30 +/- 0.052 mg/l (+/- 2 SD), generally accepted as a measure of total plasma kininogen. The SRI method does not discriminate between LMr and HMr kininogen but detects an increase of total kininogen independently of bradykinin release as a consequence of activated proteolysis. It is suggested that the SRI method can be applied to study levels of kininogen in clinical research.
D000818:Animals; D001681:Biological Assay; D001920:Bradykinin / Q000097:blood*; D000939:Epitopes / Q000032:analysis; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D005779:Immunodiffusion; D007610:Kallikreins / Q000097:blood; D007704:Kininogens / Q000097:blood* / Q000276:immunology; D008297:Male; D011863:Radioimmunoassay
D000939:Epitopes; D007704:Kininogens; D007610:Kallikreins; D001920:Bradykinin