Antibody reagents specific for IgA- alpha 1 antitrypsin complex indicative of rheumatoid arthritis

摘要

The assay of rheumatoid arthritis by reference to IgA- alpha 1 antitrypsin complex present in analytes is facilitated by ligands comprising an antibody domain specific for an antigenic determinant of a complex of human IgA and alpha 1-antitrypsin, said antibody domain being substantially non reactive with free human IgA and free human alpha 1-antitrypsin. The ligands may be monoclonal antibodies to the naturally occurring IgA- alpha 1AT complex. Alternatively monoclonal or polyclonal antibodies to a synthetic peptide, preferably including an amino acid sequence: Val-Ser-Val-Val-Met-Ala-Glu-Val-Asp-Gly-Thr-Cvs-Tyr linked by cysteine bridge to the amino acid sequence. Gly-Met-Phe- Asn-Ile-Gin-His-Cys-Lys-Lys-Leu-Ser-Ser are IgA- alpha AT specific.