Parallel detection of autoantibodies with microarrays in XXXX .

@entity1 @entity852 @entity291 @entity4166 @entity17353 @entity1252 @entity6558 @entity792 @entity309 @entity785
BACKGROUND: Clinical needs often dictate testing for several autoantibodies in a single @entity1 with evidence of @entity792 . We developed a microarray containing 15 autoantigens for the detection of autoantibodies in @entity792 . METHODS: We synthesized recombinant @entity17353 , @entity4166 , SSA 52-kDa antigen, SSA 60-kDa antigen, SSB antigen, and Jo-1 antigen and prepared anti-nuclear antibody antigens. Cyclic citrullinated peptide, histone, goat IgG for detection of rheumatoid factor, double-stranded DNA, and single-stranded DNA were purchased, as were recombinant small nuclear ribonucleoprotein U1, topoisomerase I, and Smith antigen (Sm). All 15 antigens were of @entity1 origin except @entity291 thymus Sm. Proteins were printed on @entity852 . The arrays were incubated with serum samples and then with horseradish peroxidase-conjugated secondary antibodies and chemiluminescent substrates, and light signals were captured by a charge-coupled device camera-based chip reader. Antibodies were quantified by use of calibration curves. Positive samples were confirmed by commercially available methods. RESULTS: The detection limit of the microarray system was 20 pg of IgG printed on the @entity852 support. More than 85% of the confirmed positive sera were detected as positive with the microarray system based on cutoff values established with the microarray system. The imprecision (CV) of the microarrays was <15% for all 15 autoantibody assays, with the exception of single-stranded DNA (18% and 23%) within and between batches. Characteristic autoantibody patterns were seen in @entity1 with clinical diagnoses of @entity309 (n = 83), @entity1252 (n = 71), @entity785 (n = 36), @entity6558 (n = 38), and Sjogren syndrome (n = 20). CONCLUSIONS: This microarray system provides results similar to those by conventional methods. Assessment of the diagnostic accuracy of the system remains to be done.
