Abstract: A method is disclosed for assaying a proteolytic enzyme comprising: (a) incubating an enzyme-containing sample with an immobilized fluorescence-quenched peptide having the formula Que-Sub-Flu-Spa-Car or Flu-Sub-Que-Spa-Car wherein Sub is a peptide chain containing a specific cleavage site for said proteolytic enzyme; Flu is a fluorophore; Que is a quencher capable of absorbing fluorescent radiation emitted by the fluorophore; Spa is a direct bond or a spacing chain; and Car is a water-insoluble and/or macromolecular carrier; (b) optionally separating the liquid from the carrier material; (c) irradiating said carrier material and measuring fluorescence. Also disclosed are immobilized substrates containing specific amino acid sequences for use in such an assay, especially in an assay for aggrecanase, and metalloproteinase-1, -3 and -13 activity.

Abstract: The patent application describes a sandwich-type immunoassay for the detection and/or quantitation of collagen degradation products in biological samples such as blood, serum, plasma, sputum and cell cultures. The immunoassay uses a first antibody directed at an epitope present on a collagen molecule at a distance of up to 165 amino acids from a collagen telopeptide crosslink site, and a second antibody directed at another epitope of the crosslinked collagen molecule.