The technology behind Olink® Explore enables exceptional specificity and outstanding data quality in high-multiplex protein biomarker discovery applications, and the workflow includes steps where double-stranded DNA (dsDNA) is produced during analysis. Some human autoimmune diseases such as Systemic Lupus Erythematosus (SLE) result in high blood titers of autoantibodies, including those directed against dsDNA, which could potentially interfere with the Olink analysis. In the technical note described here, we present robust evidence that Olink Explore is fully compatible with serum samples from SLE patients.
A thorough study design was used to generate multilayers of evidence that Olink Explore provides high quality proteomic data even in the presence of anti-dsDNA autoantibodies and the data were orthogonally verified using an alternative commercial protein assay technology. Protein analysis was conducted on 88 serum samples comprising healthy controls and SLE patients with varying levels of SLE associated autoantibodies measured by standard clinical diagnostics. Olink data, including standard QC evaluation, detectability and perturbed data patterns were assessed, with no evidence seen for any interference from dsDNA autoantibodies on assay performance and data quality.
The measured concentrations of anti-dsDNA antibodies were then plotted against the median NPX of all assays per sample, and this showed that the global median NPX per sample was stable and consistent across the different study groups, irrespective of autoantibody status, confirming that anti-dsDNA antibodies did not interfere with the assay or negatively impact the results. Finally, orthogonal verification of a subset of the assays measured with Olink Explore was carried out by directly comparing the data with those from a bead-based immunoassay technology (Luminex). This comparison showed a good correlation between the two methodologies in almost all cases.