Kallikreins are a subgroup of serine proteases, enzymes capable of cleaving peptide bonds in proteins.
Kallikreins are a group of serine proteases that play important roles in various physiological and pathological processes in the human body.
Kallikreins are involved in the regulation of blood pressure, inflammation, blood coagulation, fibrinolysis, and maintenance of skin barrier function.
Kallikreins are a group of serine proteases that play important roles in various physiological and pathological processes in the human body.
They are also implicated in cancer, as some kallikreins are known to be tumor markers or have prognostic value in certain types of cancer, notably prostate cancer.
One of the most well-known kallikreins is prostate-specific antigen (PSA), which is produced by the prostate gland and is commonly used as a biomarker for prostate cancer screening.
Other members of the kallikrein family include tissue kallikreins, which are expressed in various tissues and play roles in skin desquamation, wound healing, and antimicrobial defense.
Plasma kallikrein is encoded by the KLKB1 gene.
Tissue kallikrein-related peptidases (KLKs) encode a family of fifteen closely related serine proteases.
These kallikrein genes are localized to chromosome 19q13, forming the largest contiguous cluster of proteases within the human genome.
Kallikreins are responsible for the coordination of various physiological functions including blood pressure, semen liquefaction and skin desquamation.
The KLKB1 gene encoding plasma kallikrein is located on chromosome 4q34-35.
Kallikrein is synthesised as an inactive precursor, prekallikrein, which must undergo proteolytic processing to become activated, and is facilitated by factor XII, PRCP or other stimuli..
Plasma kallikrein liberates kinins (bradykinin and kallidin) from the kininogens, peptides responsible for the regulation of blood pressure and activation of inflammation.
Plasma kallikrein is also capable of generating plasmin from plasminogen:
Kallikrein is homologous to factor XI.
Distinct from plasma kallikrein, tissue kallikreins are expressed throughout the human body and perform various physiological roles.
Several cascades of kallikreins involving these proteases have been implicated in the regulation of homeostatic functions.
Three tissue kallikreins KLK1, KLK2 and KLK12 also participate in regulation of blood pressure via the activation of bradykinin.
KLK2, KLK3, KLK4, KLK5 and KLK14 are expressed in the prostate and are thought to be responsible for regulating semen liquefaction.
Desquamation of the skin is likely controlled by KLK5, KLK7 and KLK14, which are expressed in the outermost layer of the epidermis and cleave cellular adhesion proteins.
KLK6 and KLK8 are associated with neuronal plasticity in the central nervous system.
15 known human tissue kallikreins exist: KLK1, KLK2, KLK3, KLK4, KLK5, KLK6, KLK7, KLK8, KLK9, KLK10, KLK11, KLK12, KLK13, KLK14, KLK15.
Prostate-specific antigen (PSA; hk3, human kallikrein gene 3) and human glandular kallikrein (hK2) are used as tumor markers for prostate cancer.
Ecallantide, lanadelumab, and berotralstat are drugs that inhibit kallikrein and can be used for managing Hereditary Angioedema.