Patent ID: 9034592
Filing Date: 2015-05-19
Classification: C07K,G01N

Abstract:
1. An immunoassay method for determining if a patient has heart failure, comprising the steps of: a) contacting a blood sample from the patient with a first antibody, or binding fragment thereof, specific for a region of a ring structure of BNP and proBNP, the region consisting of the amino acid sequence FGRKMDRISSSS (SEQ ID NO:3) or to a portion of this region, to obtain a first order immune complex; b) contacting the first order immune complex with a second antibody, or binding fragment thereof, to obtain a second order immune complex, the second antibody, or binding fragment thereof, not recognizing free BNP, free proBNP, or a free fragment thereof, or free first antibody, or which recognizes them with 10-fold or less affinity than it recognizes the first order immune complex, the second antibody being AB-BNP2, Ab-BNP4, or a binding fragment thereof; and c) determining if the patient has heart failure by detecting a concentration of the second order immune complex in the sample, an increased concentration of the second order immune complex relative to that in a healthy subject being indicative of an increased concentration of BNP and/or proBNP in the sample and that the patient has heart failure.