Autoimmune antigen and serum factor antigen reactivity in a cohort of patients with systemic lupus erythematosus (SLE) and healthy controls from the ABCoN cohort.

The aim of the study was to test the hypothesis that SLE patient sera contains IgG reactivity to serum factor antigens concomitant with prototypical autoimmne antigens. We diluted patient sera 1:250 and incubated dilutions on a nitrocellulose-platform array printed with whole protein antigens. In this study, serum from 45 individuals (subsetted into high and low interferon signature as well as healthy control categories) was profiled for IgG autoantibody reactivity to whole protein autoimmune and serum factor antigens. SLE and specifically IFN high patient sera was found using the significance analysis of microarrays (SAM) algorithm to be significantly more reactive with prototypical autoimmune antigens and select serum factor array antigens.