Loss of B cell Tolerance is TCR Dependent [IgG2c CTD array]

We used protein arrays to measure IgG2c autoantibodies associated with Connective Tissue Diseases (CTDs) from retrogenic chimeras Sera was isolated from irradiated Icos-/-;CD45.1 mice reconstituted with 564Igi;Icos-/- bone marrow mixed with Icos-/-;CD45.1 bone marrow and WT bone marrow (BMchim.564) or retrogenic HSCs expressing TCR-A (BMchim.564-Icos.RAG-TCRA), TCR-B (BMchim.564-Icos.RAG-TCRB), or TCR-C (BMchim.564-Icos.RAG-TCRC). 564Igi (564homo) and 564Igi;Icos-/- (564homo.Icos) sera were included as controls. 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. A Luminex FLEXMAP 3D® system was used to quantitatively measure autoantibody reactivity in each sample in units of mean flourescent intensity (MFI).