Editorial High-mobility group box 1 protein (HMGB1) in ischaemic heart disease: beneficial or deleterious?

This editorial refers to ‘High-mobility group box 1 restores cardiac function after myocardial infarction in transgenic mice ’ by Kitahara et al.,4 pp. 40–46, this issue. High-mobility group box 1 (HMGB1; also known as ampho-terin) protein was identified more than 30 years ago as a non-chromosomal nuclear protein that maintains the nucleosome structure and regulates gene transcription.1 HMGB1 is highly conserved among species, has over 98% identity among all mammals, and is ubiquitously expressed in almost all types of cells. HMGB1-deficient mice are viable but die shortly after birth due to hypoglycaemia, suggesting that its nuclear functions are essential for survi-val. In 1999, Wang et al.2 discovered that HMGB1 functions as a delayed mediator in inflammatory responses in sepsi