title: T-helper cells as new players in ANCA-associated vasculitides.
abstract: In anti-neutrophil cytoplasmic autoantibody-associated vasculitides (AAV), several observations support a key role of T-helper cells (CD4(+) T cells) in disease pathophysiology. An expanded population of effector memory CD4(+) T cells in AAV patients may contribute to tissue injury and disease progression. In addition, functional impairment of regulatory T cells (T(Regs)) is reported in AAV patients. A fraction of T(Regs) have the capacity to differentiate into Th17 cells in the context of a proinflammatory environment. Therefore, nonfunctionality of T(Regs) described in AAV patients may be caused by their conversion into IL-17-producing cells that may contribute to granulomatous vasculitis. Further investigations directed at the plasticity of T(Regs) in AAV patients are warranted.
authors: Department of Rheumatology and Clinical Immunology, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands. w.abdulahad@int.umcg.nl
authors: Wayel H
authors: WH
authors: Abdulahad
authors: Peter
authors: P
authors: Lamprecht
authors: Cees G M
authors: CG
authors: Kallenberg
mesh_terms: D000818:Animals; D056648:Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / Q000276:immunology* / Q000473:pathology; D006801:Humans; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*