Changes in the composition of the upper respiratory tract microbial community in granulomatosis with polyangiitis.

Dysbiosis¸ i.e. changes in microbial composition at a mucosal interface, is implicated in the pathogenesis of many chronic inflammatory and autoimmune diseases.

Circulating CD4+CD8+ double-positive T-cells display features of innate and adaptive immune function in granulomatosis with polyangiitis.

Objectives: To examine functional features of CD4+CD8+ double-positive T-cells in patients with granulomatosis with polyangiitis (GPA) using phenotypic and transcriptomic analysis.

Methods: Staining of cellular surface marker was performed using freshly collected whole blood. For intracellular cytokine staining freshly collected whole blood was stimulated with phorbol myristate acetate and ionomycin.

Pathogenetic and Clinical Aspects of Anti-Neutrophil Cytoplasmic Autoantibody-Associated Vasculitides.

Anti-neutrophil cytoplasmic autoantibodies (ANCA) targeting proteinase 3 (PR3) and myeloperoxidase expressed by innate immune cells (neutrophils and monocytes) are salient diagnostic and pathogenic features of small vessel vasculitis, comprising granulomatosis with polyangiitis (GPA), microscopic polyangiitis, and eosinophilic GPA. Genetic studies suggest that ANCA-associated vasculitides (AAV) constitute separate diseases, which share common immunological and pathological features, but are otherwise heterogeneous. The successful therapeutic use of anti-CD20 antibodies emphasizes the prominent role of ANCA and possibly other autoantibodies in the pathogenesis of AAV.

[Granulomatosis with polyangiitis].

Granulomatosis with polyangiitis (GPA) is a potentially life-threatening, rare disease. The etiology is unknown. GPA is histomorphologically characterized by extravascular necrotizing granulomatous inflammation and a systemic necrotizing vasculitis of small to medium-sized vessels.

Environmental factor and inflammation-driven alteration of the total peripheral T-cell compartment in granulomatosis with polyangiitis.

Autoimmune diseases are initiated by a combination of predisposing genetic and environmental factors resulting in self-perpetuating chronic inflammation and tissue damage. Autoantibody production and an imbalance of effector and regulatory T-cells are hallmarks of autoimmune dysregulation. While expansion of circulating effector memory T-cells is linked to disease pathogenesis and progression, the causes driving alterations of the peripheral T-cell compartment have remained poorly understood so far.