Common Connective Tissue Disorder and Anti-Cytokine Autoantibodies are Enriched in Idiopathic Multicentric Castleman Disease Patients [Protein Fragment Array]

We measued IgG autoantibodies associated with Connective Tissue Diseases (CTDs) and Anti-Cytokine Antibodies (ACA) in idiopathic Multicentric Castleman Disease (iMCD) patients and healthy controls who received the BNT162b2 vaccine. We constructed protein arrays by coupling recombinant protein antigens to fluorescent carboxylated magnetic beads and then combined the beads into two seperate arrays (i.e., the CTD and ACA arrays). We then used the protein arrays to probe iMCD patient serum samples, healthy control samples, and Hodgekin lymphoma patients for IgG autoantibodies. A Luminex FLEXMAP 3D® system was used to quantitatively measure autoantibody reactivity in units of mean flourescent intensity (MFI).