Structural determinants of mitochondrial STAT3 targeting and function.

Signal transducer and activator of transcription (STAT) 3 has been found within mitochondria in addition to its canonical role of shuttling between cytoplasm and nucleus during cytokine signaling. Mitochondrial STAT3 has been implicated in modulation of cellular metabolism, largely through effects on the respiratory electron transport chain. However, the structural requirements underlying mitochondrial targeting and function have remained unclear.

Potential efficacy of T and B lymphocyte-targeted therapies on articular involvement of patients with rheumatoid arthritis and systemic sclerosis overlap syndrome. Results from a 2-centre series of 19 cases.

Objectives: To analyse in routine practice the efficacy of targeted therapies on joint involvement of patients with rheumatoid arthritis/systemic sclerosis (RA/SSc) overlap syndrome.

Methods: This was a retrospective analysis of medical records of two academic centres over a 10-year period. Joint response to targeted therapies was measured according to EULAR criteria based on Disease Activity Score (DAS)-28.

Donor T cell STAT3 deficiency enables tissue PD-L1-dependent prevention of graft-versus-host disease while preserving graft-versus-leukemia activity.

STAT3 deficiency (STAT3-/-) in donor T cells prevents graft-versus-host disease (GVHD), but the impact on graft-versus-leukemia (GVL) activity and mechanisms of GVHD prevention remains unclear. Here, using murine models of GVHD, we show that STAT3-/- donor T cells induced only mild reversible acute GVHD while preserving GVL effects against nonsusceptible acute lymphoblastic leukemia (ALL) cells in a donor T cell dose-dependent manner. GVHD prevention depended on programmed death ligand 1/programmed cell death protein 1 (PD-L1/PD-1) signaling.