pentraxin3

Pentraxin 3, also known as PTX3 or TSG-14, is a member of the pentraxin family of proteins. It is a long pentraxin, distinguished from the short pentraxins like C-reactive protein (CRP) by its distinct structure and longer C-terminal pentraxin-like domain. PTX3 is primarily produced by myeloid cells, such as monocytes and dendritic cells, as well as by other cell types including endothelial cells and adipocytes. Its expression is rapidly induced by inflammatory stimuli, particularly by cytokines like TNF-alpha and IL-1beta, as well as by pattern recognition receptor signaling.

The physiological roles of PTX3 are diverse and are primarily associated with innate immunity and inflammation. It acts as a pattern recognition molecule, binding to various microbial structures and endogenous danger signals. PTX3 plays a crucial role in host defense against bacterial, fungal, and viral infections by mediating opsonization, which facilitates phagocytosis by immune cells, and by inhibiting complement activation on self-cells, thus preventing autoimmune damage. Beyond infection, PTX3 is involved in regulating inflammation by modulating the activity of other inflammatory mediators and by influencing the recruitment and activation of immune cells. Elevated levels of PTX3 are observed in various inflammatory and cardiovascular conditions, including sepsis, atherosclerosis, myocardial infarction, and rheumatoid arthritis, suggesting its utility as a biomarker for inflammation and tissue injury. Its involvement in angiogenesis and tissue remodeling further highlights its complex role in health and disease.