Role of HMGB1 in rheumatic diseases / 浙江大学学报·医学版

ABSTRACT

High mobility group box chromosomal protein 1 (HMGB1) is originally identified as a DNA-binding protein that functions as a structural co-factor. HMGB1 is actively secreted by macrophage/monocytes via inflammatory stimuli. The extracellular HMGB-1 acts as a mediator of acute and chronic systematic inflammation. In this article we briefly review its role in rheumatic diseases arthritis, polymyositis and dermatomyositis, lupus erythematosus and Sjogren's syndrome. Increased cytoplasmic expression and extracellular deposition of HMGB1 are found in the affected tissues of those diseases, especially stronger in/around focal infiltrates of mononuclear cells. TNFalpha and IL-1beta are co-expressed in areas of extracellular HMGB1. HMGB1 together with TNF alpha and IL-1beta may form a proinflammatory loop promoting the chronic inflammations. The new findings of HMGB1 as a cytokine provide a better understanding of rheumatiod diseases, and could become a clinically relevant therapeutic target that might be more efficient than other known cytokines.