HMGB1 is a protein that is normally present in the nucleus and cytoplasm of mammalian cells, and is involved in gene transcription as a chromatin binder. It can then either be released passively as a soluble molecule from necrotic cells, or may be actively secreted from inflammatory cells.
Thus, HMGB1 acts as a cytokine, exhibiting similar pro-inflammatory effects as do TNF- and IL-6. Any disease coping with dying, necrotic cells will therefore be involved with HMGB1 in one of these two cases.
IBL offers the only commercial ELISA worldwide for measuring HMGB1.