The gene expression profile of CD4 T-cells with STAT3 gain-of-function and loss-of-function mutations

Purpose: Recently discovered activating Interleukin-6 receptor subunit beta (IL6ST, encoding glycoprotein 130 (gp130)) mutations, as well as germline Signal transducer and activator of transcription 3 (STAT3) gain-of-function mutations are associated with multi-organ autoimmunity, severe morbidity, and adverse prognosis, resulting in an unmet medical need. Methods: To decipher the crucial cellular subsets and disease biology associated with STAT3 gain-of-function mutations, we examined the gene expression profile of STAT3 gain-of-function and loss-of-function mutations in unstimulated, IL10- or IL21-stimulated CD4 T cells and compared them to healthy donor cells. Results: Activating gp130 signaling in vivo resulted in fatal early-onset multi-organ autoimmunity, resembling numerous clinical features of human STAT3 gain-of-function disease. We observed strong T-cell activation and effector differentiation, accompanied by TH17 expansion and interferon-gamma production. Transcriptome profiling of murine CD4+ and CD8+ T-cells revealed commonly dysregulated genes and a STAT3 gain-of-function signature that was used to discriminate between STAT3 gain-of-function and healthy control patients. Conclusions: Hyperactive gp130/STAT3 signaling leads to strong TH17-mediated autoimmunity phenotypically resembling human STAT3 gain-of-function disease and identify TH17-cells as a key cellular subset for initiation and maintenance of autoimmunity gene expression profile of STAT3 gain-of-function and loss-of-function mutations in unstimulated, IL10- or IL21-stimulated CD4 T cells and compared them to healthy donor cells.