Page 67 - Veterinary Immunology, 10th Edition
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FIG. 2.8 The properties of HMGB1. Released from “broken” cells,
HMGB1 activates many of the cells associated with inflammation
and triggers systemic responses causing septic shock.
Many molecules released from broken cells act as intracellular
DAMPs. These include adenosine and adenosine triphosphate, uric
acid, S100 proteins (a family of calcium-binding proteins involved
in cell growth and tissue injury), and heat-shock proteins (Chapter
26). An important extracellular DAMP is heparan sulfate. This
molecule is normally found in cell membranes and the extracellular
matrix but is shed into tissue fluids following injury. Heparan
sulfate binds and triggers TLR4. Other extracellular DAMPs include
hyaluronic acid, fibronectin, and peptides from collagen and elastin
(Fig. 2.9).
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