Project description:We tested orphan TCR autoreactivity using the peptide MHC-TCR chimeric receptor (MCR) co-culture system. In this system, cognate antigen recognition leads to TCR specific NFAT activation in MCR reporter cells expressing a mouse I-Ab MHC class II extracellular domain covalently linked to candidate peptides and an intracellular TCR signaling domain. We used mixed autoimmune bone marrow chimera spleens and kidneys as sources of cDNA to generate a transcriptome-wide library of natural autoantigen peptides . We cloned this cDNA-derived peptide (CDP) autoantigen library into the MCR retroviral backbone and transduced NFAT reporter cells to make a murine autoantigen MCR reporter library (MCR-Lib). We then used this library to screen orphan TCRs identified by scTCR-seq for autoreactivity.
Project description: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.
Project description:We used protein arrays to measure IgG2a 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.
Project description:We used protein arrays to measure IgG 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.
Project description:Roughly one-half of mice with partial defects in two immune tolerance pathways (AireGW/+Lyn-/- mice) spontaneously develop severe damage to their retinas due to T cell reactivity to Aire-regulated interphotoreceptor retinoid-binding protein (IRBP). Single cell T cell receptor (TCR) sequencing of CD4+ T cells specific for a predominate epitope of IRBP showed a remarkable diversity of autoantigen-specific TCRs with greater clonal expansions in mice with disease. TCR transgenic mice made with an expanded IRBP-specific TCR (P2.U2) of intermediate affinity exhibited strong but incomplete negative selection of thymocytes. This negative selection was absent in IRBP-/- mice and greatly defective in AireGW/+ mice. Most P2.U2+/- mice and all P2.U.2+/-AireGW/+ mice rapidly developed inflammation of the retina and adjacent uvea (uveitis). Aire-dependent IRBP expression in the thymus also promoted Treg differentiation, but the niche for this fate determination was small, suggesting differences in antigen presentation leading to negative selection vs. thymic Treg differentiation and a stronger role for negative selection in preventing autoimmune disease in the retina.