secretory leukocyte protease inhibitor

Secretory leukocyte protease inhibitor (SLPI) is a 12 kDa, non-glycosylated, cysteine-rich protein that functions as a protease inhibitor. It contains eight intramolecular disulfide bonds and is structured with two homologous domains, with the C-terminal domain exhibiting anti-protease activity. SLPI is found in bronchial, cervical, and nasal mucosa, saliva, and seminal fluids. It primarily protects tissues against inflammation by inhibiting serine proteases, especially neutrophil-derived serine proteases including cathepsin G and elastase. Beyond its protease inhibitory function, SLPI demonstrates antimicrobial properties against certain bacteria and fungi, and has shown anti-HIV-1 activity. It also exerts anti-inflammatory effects by inhibiting NF-κB activation in macrophages.

Other names

antileukoproteinaseSLPIALK1ALK-1ALK 1ALPBLPIHUSIHUSI-IMPIWAP4WAP-4WAP 4WFDC4WFDC-4WFDC 4mucus proteinase inhibitor