Kallikrein-related peptidase 5 contributes to the remodeling and repair of bronchial epithelium.

Inflammation, oxidative stress, and protease/protease inhibitor imbalance with excessive production of proteases are factors associated with pathogenesis of the chronic obstructive pulmonary disease (COPD). In this study, we report that kallikrein-related peptidase 5 (KLK5) is a crucial protease involved in extracellular matrix (ECM) remodeling and bronchial epithelial repair after injury. First, we showed that KLK5 degrades the basal layer formed by culture of primary bronchial epithelial cells from COPD or non-COPD patients.

Tissue factor pathway inhibitor 2 is a potent kallikrein-related protease 12 inhibitor.

The protease activities are tightly regulated by inhibitors and dysregulation contribute to pathological processes such as cancer and inflammatory disorders. Tissue factor pathway inhibitor 2 (TFPI-2) is a serine proteases inhibitor, that mainly inhibits plasmin. This protease activated matrix metalloproteases (MMPs) and degraded extracellular matrix.

Structure, function, and evolution of -AvBD11, the archetype of the structural avian-double-β-defensin family.

Out of the 14 avian β-defensins identified in the genome, only 3 are present in the chicken egg, including the egg-specific avian β-defensin 11 (-AvBD11). Given its specific localization and its established antibacterial activity, -AvBD11 appears to play a protective role in embryonic development. -AvBD11 is an atypical double-sized defensin, predicted to possess 2 motifs related to β-defensins and 6 disulfide bridges.

Human kallikrein-related peptidase 12 stimulates endothelial cell migration by remodeling the fibronectin matrix.

Kallikrein-related peptidase 12 (KLK12) is a kallikrein family peptidase involved in angiogenesis - a complex biological process in which the sprouting, migration and stabilization of endothelial cells requires extracellular matrix remodeling. To characterize the molecular mechanisms associated with KLK12's proangiogenic activity, we evaluated its ability to hydrolyze various matrix proteins. Our results show that KLK12 efficiently cleaved the human extracellular matrix proteins fibronectin and tenascin, both of which are involved in the regulation of endothelial cell adhesion and migration.

Kallikrein-related peptidases in lung diseases.

Human tissue kallikreins (KLKs) are 15 members of the serine protease family and are present in various healthy human tissues including airway tissues. Multiple studies have revealed their crucial role in the pathophysiology of a number of chronic, infectious and tumour lung diseases. KLK1, 3 and 14 are involved in asthma pathogenesis, and KLK1 could be also associated with the exacerbation of this inflammatory disease caused by rhinovirus.