Secretory Leukocyte Peptidase Inhibitor (SLPI)

Secretory leukoprotease inhibitor (SLPI), also called antileukoprotease (ALP), is a 12-kDa, nonglycosylated serine protease inhibitor present in mucous secretions. It is thought to play a role in protecting the mucosae from injury associated with inflammation. SLPI is locally produced by serous cells, including bronchial submucosal glands. Elafin and SLPI are members of larger families of proteins secreted predominantly at mucosal sites, and have been shown to be modulated in multiple pathological conditions. Elafin and SLPI are structurally related in that both have a fold with a four-disulfide core or whey acidic protein (WAP) domain responsible for inhibiting proteases. SLPI is a prominent innate immune protein of the respiratory tract, possessing serine protease inhibitor activity, antibacterial activity, and anti-inflammatory/immunomodulatory activity.

Secretory Leukocyte Peptidase Inhibitor (SLPI) Related Areas

Enzyme>>Protease & Regulator>>Serine Protease & Regulator>>SLPI

Immunology>>Adaptive Immunity>>B Cell>>SLPI

Immunology>>Innate Immunity>>Monocyte/Macrophage>>Macrophage Marker>>SLPI

Secretory Leukocyte Peptidase Inhibitor (SLPI) Alternative Names

SLPI, ALK1, ALP, BLPI, HUSI, HUSI-I, MPI, WAP4, WFDC4 [Homo sapiens]

Slpi, RP23-462O16.7 [Mus musculus]

Summaries for Secretory Leukocyte Peptidase Inhibitor (SLPI)

Entrez Gene summary for Secretory Leukocyte Peptidase Inhibitor (SLPI):

Secretory leukocyte peptidase inhibitor gene encodes a secreted inhibitor which protects epithelial tissues from serine proteases. It is found in various secretions including seminal plasma, cervical mucus, and bronchial secretions, and has affinity for trypsin, leukocyte elastase, and cathepsin G. Its inhibitory effect contributes to the immune response by protecting epithelial surfaces from attack by endogenous proteolytic enzymes; the protein is also thought to have broad-spectrum anti-biotic activity. [provided by RefSeq, Jul 2008]

OMIM - description for Secretory Leukocyte Peptidase Inhibitor (SLPI):

Human mucous fluids such as seminal plasma, cervical mucus, bronchial and nasal secretions, and tears contain acid-stable proteinase inhibitors with strong affinity for trypsin and chymotrypsin as well as for neutrophil lysosomal elastase and cathepsin G. The antileukoprotease from human seminal plasma HUSI-I (human seminal plasma inhibitor-I) and the inhibitor found in mucous secretions from the cervix, although isolated from different tissues, seem to be identical proteins (summary by Seemuller et al., 1986).

Wikipedia summary for Secretory Leukocyte Peptidase Inhibitor (SLPI):

Antileukoproteinase is an enzyme that in humans is encoded by the SLPI gene.
This gene encodes a secreted inhibitor which protects epithelial tissues from serine proteases. It is found in various secretions including seminal plasma, cervical mucus, and bronchial secretions, and has affinity for trypsin, leukocyte elastase, and cathepsin G. Its inhibitory effect contributes to the immune response by protecting epithelial surfaces from attack by endogenous proteolytic enzymes; the protein is also thought to have broad-spectrum anti-biotic activity.

Human Secretory Leukocyte Peptidase Inhibitor (SLPI) Protein General Information

 

• Protein names: Secretory Leukocyte Peptidase Inhibitor
  Short name=SLPI
• Sequence length: 132 AA.
• Domain: Repeat
  Signal
• Sequence similarities: Contains 2 WAP domains.
• Miscellaneous: The pathologies of several chronic and acute diseases of the respiratory tract involve an imbalance between the proteases of cells involved in inflammatary responses and the inhibitors of these proteases. The inflammation-mediated release of neutrophil elastase in the lungs of patients whose levels of active alpha-1-antiprotease are compromised by genetic background, cigarette smoking, air pollutants, or a combination of all three can result in severe lung damage and a decreased lifespan. The relatively small size of this protein, its lack of glycosylation and its stability make this protein a candidate for use as a therapeutic agent in diseases mediated by leukocyte elastase-antielastase imbalances.
• Subcellular location: Secreted.
• Tissue specificity: Mucous fluids.

General information above from UniProt

Function for Secretory Leukocyte Peptidase Inhibitor (SLPI) Protein

UniProtKB:

Secretory leukocyte peptidase inhibitor is acid-stable proteinase inhibitor with strong affinities for trypsin, chymotrypsin, elastase, and cathepsin G. SLPI may prevent elastase-mediated damage to oral and possibly other mucosal tissues.

Genatlas:

• SLPI is secretory leukoprotease inhibitor
• SLPI is involved in antineutrophil elastase protection at inflammatory sites
protects epithelial tissues from serine proteases
• SLPI is prominent innate immune protein of the respiratory tract, possessing serine protease inhibitor activity, antibacterial activity, and anti-inflammatory/immunomodulatory activity (Weldon 2007)
• SLPI can inhibit interferon-gamma-induced cathepsin S production by macrophages (Geraghty 2007)
• SLPI is cationic non-glycosylated antiprotease synthesized and secreted by cells at the site of inflammation (Geraghty 2007)
• SLPI is able to disrupt the association between PLSCR1 and CD4, suggesting that SLPI inhibits HIV-1 infection by modulating the interaction of the CD4 receptor with PLSCRs (Py 2009)

Homology for human Secretory Leukocyte Peptidase Inhibitor (SLPI)

• homolog to murine Slpi
• homolog to C.elegans c45g7.3