Quantification of C1 esterase inhibitor in human serum by enzyme-linked immunosorbent assay: Correlation with turbidimetric immunoassay

C1 inhibitor of serine proteases (C1-INH) performs a regulatory function in the complement system and vascular permeability. Deficiency C1-INH leads to various forms angioedema, including hereditary angioedema (HAE). The cause HAE is genetically determined violation synthesis C1-INH. A decrease level 50% relative norm an increase production bradykinin, which basis for diagnosis HAE. development affordable ELISA quantitative determination popular direction clinicians. During new kit C1-INH, two mouse monoclonal antibodies (mAb) with different epitope specificities were obtained. On their basis, sandwich-type was developed. specificity obtained mAb's confirmed using medical device “Berinert”. To prepare calibrators, affinity purified from human blood plasma sorbent immobilized mAbs. identity protein by PAGE electrophoresis, immunoblotting, mass spectrometry on MALDI-TOF/TOF UltrafleXtreme spectrometer. assess quality indicators developed reagents kit, studies carried out accordance GOST R 51352-2013 TU 21.20.23-041-01967164-2022. Values indicators: accuracy — 93.53%; measurement linearity interval 22.00-176.07 ng/mL. Using test system, we examined 28 sera healthy donors 7 patients In same samples, content turbidimetric method, "Diagnostic vitro immunochemical specific proteins. Model: C1-esterase (C1 EsteraseInhibitor)" (Aptec, Belgium). correlation coefficient 0.94 (p < 0.05). It found that diagnostic sensitivity 100%. As result study, original "Reagent enzyme-linked immunosorbent assay C1-inhibitor (C1-inh PS)".