The eosinophil cationic protein (ECP) is a basic secretion protein involved in the immune response system. ECP levels in biological fluids are an indicator of eosinophil-specific activation and degranulation and are currently used for the clinical monitoring and diagnosis of inflammatory disorders. A polyclonal epitope-specific antibody has been obtained by immunizing rabbits with a conjugated synthetic peptide. A sequence corresponding to a large exposed loop in the human ECP three-dimensional structure (D115-Y122) was selected as a putative antigenic epitope. The antibody was purified on an affinity column using recombinant ECP (rECP) as antigen. The antibody (D112P123 Ab) specifically recognizes rECP and its native glycosylated and nonglycosylated forms in plasma, granulocytes, and sputum. The antibody detects as little as Ing of rECP, can be used both in reducing and nonreducing conditions, and does not cross-react with the highly homologous eosinophil-derived neurotoxin or other proteins of the pancreatic ribonuclease superfamily.
|Journal||Journal of Leukocyte Biology|
|Publication status||Published - 7 Jul 2001|