Autoantibodies are highly prevalent in non-SARS-CoV-2 respiratory infections and critical illness [CTD]. Autoantibodies are highly prevalent in non-SARS-CoV-2 respiratory infections and critical illness [CTD]

We used protein arrays to measure IgG autoantibodies associated with Connective Tissue Diseases (CTDs) and Anti-Cytokine Antibodies (ACA) in patients with non-COVID-19 infections such as influenza Overall design: Protein arrays were constructed by coupling antigens to carboxylated magnetic beads. Arrays consisting of conjugated beads were then used to probe patient serum or plasma samples, healthy control samples, and autoimmune prototype samples. Samples were run in duplicate except one sample (UP67 D7) which was run in quadruplicate. for A Luminex FLEXMAP 3D® system was used to quantitatively measure autoantibody reactivity in each sample in units of mean flourescent intensity (MFI). Positive antibody hits were statistically identified by a 5 standard deviation cutoff calculated from the MFI of healthy controls.