Work

Vascular damage in giant cell arteritis

Year: 2009

Type: article

Abstract: Immune-mediated damage to medium-sized arteries results in wall remodeling with intimal hyperplasia, luminal stenosis and tissue ischemia. In the case of the aorta, vasculitis may result in dissection, aneurysm or rupture. The response-to-injury program of the blood vessel is a concerted action between the immune system and wall-resident cells, involving the release of growth and angiogenic factors from macrophages and giant cells and the migration and hyperproliferation of vascular smooth muscle cells. Innate immune cells, specifically, dendritic cells (DC) positioned in the vessel wall, have been implicated in the earliest steps of vasculitis. Pathogen-derived molecular patterns are capable of activating vascular DC and initiating adaptive immune responses. The pattern of the emerging vessel wall inflammation is ultimately determined by the initial insult. Ligands to toll-like receptor (TLR) 4, such as lipopolysaccharides, facilitate the recruitment of CD4 T cells that invade deep into the wall and distribute in a panarteritic pattern. Conversely, ligands for TLR5 condition vascular DC to support perivasculitic infiltrates. In essence, both innate and adaptive immune reactions collaborate to render the arterial wall susceptible to inflammatory damage. Unique features of the tissue microenvironment, including specialized DC, shape the course of the inflammatory response. Differences in vascular damage pattern encountered in different patients may relate to distinct instigators of vasculitis.

Source: Autoimmunity

DOI: 10.1080/08916930903002495

Authors: Kisha Piggott, Valerie Biousse, Nancy J. Newman, Jőrg J. Goronzy, Cornelia M. Weyand

Institution: Emory University

Language: English

Topic: Vasculitis and related conditions

Subfield: Pulmonary and Respiratory Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: green