Detection and Characterization of Autoantibodies Against Modified Self-Proteins in SLE Sera After Exposure to Reactive Oxygen and Nitrogen Species

There are over 120 types of autoantibodies found in the blood of SLE patients against cellular and extracellular components in both their native and posttranslationally modified forms. In recent years, these autoantibodies have provoked interest as initiators of pathology and as biomarkers of disease activity. Often, the host antigens employed in lab-based and commercially developed immunoassays use non-human antigen or non-modified host antigen as a probe for autoantibodies. Here, we describe methods to posttranslationally modify host antigens, which better represent the antigen recognized by autoantibodies in vivo. This has implications in developing immunoassay with greater sensitivity and specificity.