| CPC G01N 33/564 (2013.01) [G01N 33/6893 (2013.01); G01N 2440/18 (2013.01); G01N 2800/102 (2013.01); G01N 2800/52 (2013.01)] | 7 Claims |
|
1. A method of detecting anti-citrullinated antibodies in a sample from a rheumatoid arthritis patient, comprising the steps of:
(i) contacting a plasma or serum sample obtained from the patient with a substrate comprising
at least one in vitro citrullinated antigen selected from the group consisting of a Myelin Basic Protein (MBP) peptide fragment consisting of the sequence of SEQ ID NO. 1, and an MBP peptide fragment consisting of the sequence of SEQ ID NO. 2 and
at least one additional in vitro citrullinated antigen selected from the group consisting of osteopontin (SPP1), flap endonuclease (FEN1), insulin like growth factor binding protein 6 (IGFBP6), insulin like growth factor I (IGF1), and stanniocalcin-2 (STC2) to form antibody-antigen complexes; wherein the at least one antigen and the at least one additional antigen are each linked to a haloalkane dehalogenase, wherein the substrate is coated with a ligand comprising a reactive chloroalkane capable of binding the haloalkane dehalogenase, thereby immobilizing the at least one antigen and the at least one additional antigen on the substrate;
(ii) contacting the antibody-antigen complexes with a label; and
(iii) detecting the antibody-antigen complexes, thereby detecting the anti-citrullinated antibodies in the sample by detecting the label.
|