Kallikrein 1

Kallikreins are serine protease enzymes with various physiological functions. Kallikreins are associated with carcinogenesis and have the potential to be novel biomarkers for cancer. KLK1 (molecular weight28-32 kDa), also called stratum corneum tryptic enzyme, is one of the fifteen members of the kallikrein subfamily located in a cluster on chromosome 19. The enzyme KLK1 is functionally conserved in its ability to release the vasoactive peptide Lys-Bradykinin from low molecular weight kininogen. Kallikrein-1 is encoded by the gene of the same name on chromosome 19q13.33.

Human kallikrein-1 is an active protein enzyme found in saliva, pancreatic juice and urine that catalyzes the proteolysis of bradykininogen to bradykinin.

Kallikrein-1, which comes from humans or pigs, has long been used as a drug, especially for the treatment of mild to moderate hypertension and occlusion of cerebral and surrounding blood vessels.

All members of the kallikrein family exhibit trypsin- or chymotrypsin-like activities. KLK5, KLK7 and KLK14 are three prominent members involved in epidermal desquamation.

In situ hybridization methods confirmed the expression of KLK1 mRNA in eccrine sweat glands (Komatsu N et al. 2003), but also in the stratum granulosum of normal epidermis and in the inner root sheath of the hair follicle epithelium (Komatsu N et al. 2003).

1. Komatsu N et al. (2003) Expression and localization of tissue kallikrein mRNAs in human epidermis and appendages. J Invest Dermatol 121: 542-549.

2. Matus CE et al. (2022) The family of kallikrein-related peptidases and kinin peptides as modulators of epidermal homeostasis. Am J Physiol Cell Physiol 323:C1070-C1087.
3. Takano M et al. (2000) Tissue-specific expression of rat kininogen mRNAs. Biol Pharm Bull 23: 1239-1242.
4. Yamamoto T et al. (1987) Interstitial-tissue localization of high-molecular-weight kininogen in guinea-pig skin. Biochim Biophys Acta 916: 332-342.