proinflammatory

Proinflammatory is an adjective describing processes, signals, or mediators that promote inflammation. In immunology, inflammation is a protective response to infection or injury, involving vascular changes, recruitment of leukocytes, and production of mediator molecules. Proinflammatory mediators include cytokines such as TNF-α, IL-1β, and IL-6; chemokines that attract immune cells; lipid mediators such as prostaglandins (e.g., PGE2) and leukotrienes; and nitric oxide. Cellular sources include macrophages, dendritic cells, mast cells, neutrophils, and damaged tissue cells. Proinflammatory signaling often activates transcription factors like NF-κB and MAP kinases and can involve inflammasomes (e.g., NLRP3) that promote IL-1β processing.

In physiology, proinflammatory responses help contain pathogens, clear debris, and initiate tissue repair during acute inflammation. However, persistent or excessive proinflammatory signaling can cause tissue damage and contribute to chronic inflammatory diseases such as atherosclerosis, rheumatoid arthritis, inflammatory bowel disease, and certain neurodegenerative disorders. The outcome is shaped by regulation with anti-inflammatory mediators, including IL-10, transforming growth factor-beta (TGF-β), regulatory T cells, and glucocorticoids. Clinically, downstream effects like elevated C-reactive protein can indicate a proinflammatory state, though such markers are non-specific. The term is used to classify stimuli, cells, or conditions that promote inflammation rather than suppress it.