RESUMO
Pathogenic autoantibodies arise in many autoimmune diseases, but it is not understood how the cells making them evade immune checkpoints. Here, single-cell multi-omics analysis demonstrates a shared mechanism with lymphoid malignancy in the formation of public rheumatoid factor autoantibodies responsible for mixed cryoglobulinemic vasculitis. By combining single-cell DNA and RNA sequencing with serum antibody peptide sequencing and antibody synthesis, rare circulating B lymphocytes making pathogenic autoantibodies were found to comprise clonal trees accumulating mutations. Lymphoma driver mutations in genes regulating B cell proliferation and V(D)J mutation (CARD11, TNFAIP3, CCND3, ID3, BTG2, and KLHL6) were present in rogue B cells producing the pathogenic autoantibody. Antibody V(D)J mutations conferred pathogenicity by causing the antigen-bound autoantibodies to undergo phase transition to insoluble aggregates at lower temperatures. These results reveal a pre-neoplastic stage in human lymphomagenesis and a cascade of somatic mutations leading to an iconic pathogenic autoantibody.
Assuntos
Autoanticorpos/genética , Doenças Autoimunes/genética , Linfócitos B/imunologia , Linfoma/genética , Animais , Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Linfócitos B/patologia , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas de Transporte/genética , Evolução Clonal/genética , Evolução Clonal/imunologia , Ciclina D3/genética , Guanilato Ciclase/genética , Humanos , Proteínas Imediatamente Precoces/genética , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Proteínas Inibidoras de Diferenciação/genética , Linfoma/imunologia , Linfoma/patologia , Camundongos , Mutação/genética , Mutação/imunologia , Proteínas de Neoplasias/genética , Análise de Sequência de DNA/métodos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Proteínas Supressoras de Tumor/genética , Recombinação V(D)J/genéticaRESUMO
MicroRNA (miRNA) regulation clearly impacts animal development, but the extent to which development-with its resulting diversity of cellular contexts-impacts miRNA regulation is unclear. Here, we compared cohorts of genes repressed by the same miRNAs in different cell lines and tissues and found that target repertoires were largely unaffected, with secondary effects explaining most of the differential responses detected. Outliers resulting from differential direct targeting were often attributable to alternative 3' UTR isoform usage that modulated the presence of miRNA sites. More inclusive examination of alternative 3' UTR isoforms revealed that they influence â¼10% of predicted targets when comparing any two cell types. Indeed, considering alternative 3' UTR isoform usage improved prediction of targeting efficacy significantly beyond the improvements observed when considering constitutive isoform usage. Thus, although miRNA targeting is remarkably consistent in different cell types, considering the 3' UTR landscape helps predict targeting efficacy and explain differential regulation that is observed.