[Pathophysiology of giant cell arteritis]

Abstract

Giant cell arteritis is a large-vessel vasculitis affecting all three layers of the arterial wall. Histopathology of this vasculitis consists of an inflammatory infiltrate with CD4(+) T cells, macrophages, multinucleated giant cells, forming granulomas in the media. This infiltrate is associated with a destruction of the arterial wall, a fragmentation of the internal elastic lamina and a vascular remodeling leading to intimal hyperplasia. Recent studies have clarified the role of Th17 cells in the initial phase of the disease, pro-inflammatory cytokines and vascular smooth muscle cells in vascular remodeling. This review aims to update data on giant cell arteritis pathogenesis and to propose clues of investigation for a better understanding of this condition.