Secretory leukocyte peptidase inhibitor (SLPI) belongs to the whey acidic protein four-disulfide core (WFDC) family of proteins. It is a single polypeptide cationic protein of 107 amino acids. It is also known as antileukoprotease (ALP), bronchial secretory inhibitor (BI), human seminal inhibitor I (HUSI-I), cervix uterine secretion inhibitor (CUSI), mucous proteinase inhibitor (MPI), or secretory leukoprotease inhibitor (SLI). SLPI is produced by the epithelial cells lining the respiratory, digestive, and reproductive tracts. The well-known function of SLPI is the inhibition of serine proteases including human neutrophil elastase and cathepsin G. Gene-targeting experiments in mice indicated that SLPI protect proepithelin from cleavage by elastase in wound healing. SLPI participates in anti-inflammatory function through the modulation of nuclear factor-κB by acting intracellularly, especially in macrophages. It can also inhibit bacterial growth and block HIV infection of macrophages. SLPI is strongly up-regulated in response to CNS injury and that exogenous administration of SLPI is neuroprotective. SLPI is also produced in cancer tissues, but its role in cancer is not well understood. SLPI expression is highly upregulated in pancreatic, papillary thyroid, uterine cervix, endometrial, and ovarian cancer; by contrast, SLPI is underexpressed in nasopharyngeal carcinoma, bladder tumors, and some breast carcinoma. In breast carcinoma, overexpression of SLPI correlates with more-invasive forms.
Size
25 μg
Concentration
n/a
Applications
BA
Other Names
Antileukoprotease (ALP), Mucus proteinase Inhibitor (MPI), bronchial secretory inhibitor (BI), human seminal inhibitor I (HUSI-I), cervix uterine secretion inhibitor (CUSI)