Cell damage

Cell damage or stress can be triggered by various factors, including tissue injury, radiation, drug treatment, infection, and ischemic shock. These triggers lead to the production of Damage-Associated Molecular Patterns (DAMPs). DAMPs are released into the cytoplasm by disrupted or stressed organelles or into the extracellular space by damaged cells.

DAMPs are recognized by

• cytosolic or endosomal receptors for intracellular DAMPs


• membrane receptors for extracellular DAMPs

DAMP-sensing receptors are expressed not only by immune cells (Macrophages, dendritic cells (DCs), eosinophils, neutrophils, mast cells, T cells, B cells) but also by non-immune cells (Epithelial cells, fibroblasts, and endothelial cells).

Upon interaction with DAMP-sensing receptors, DAMPs activate multiple signaling pathways. This activation leads to:

• Release of inflammatory mediators.


• Phagocytosis.


• Recruitment of immune cells.


• Immunoregulation.

These processes culminate in an inflammatory response aimed at addressing the danger situation or repairing damaged tissue.

References:

(1) Ma et al. 2024 Immunity 57(4): 752-771