2. Signaling Pathways
  3. Immunology/Inflammation
  4. Kallikrein
  5. KLK5 Isoform

KLK5

Kallikrein-related peptidase 5 (KLK5) is a serine protease predominantly expressed in the epidermis, where it regulates desquamation and maintains skin barrier homeostasis[1][2]. Mechanistically, KLK5 initiates a proteolytic cascade by activating downstream kallikreins such as KLK7, which amplifies epidermal proteolytic activity[1]. Dysregulated KLK5 activity contributes to skin pathologies, including Netherton syndrome and rosacea, by promoting overproduction of antimicrobial peptide LL-37 and inducing inflammatory signaling via TLR4/NF-κB pathways[2]. In experimental models, genetic ablation of KLK5 in Spink5-deficient mice attenuates disease phenotypes, confirming KLK5 as a critical driver of proteolytic and inflammatory processes in vivo[1]. Compared with related isoforms such as KLK7 and KLK8, KLK5 exhibits a unique substrate specificity and tissue localization, distinguishing its functional contributions to epidermal homeostasis and disease[1][3]. Small molecule inhibitors and natural compounds like lithospermic acid have demonstrated selective KLK5 inhibition, reducing pro-inflammatory cytokines and restoring metabolic balance in experimental rosacea models[2]. These pharmacological tools enable precise modulation of KLK5 activity, supporting its utility in preclinical studies and potential therapeutic development[2][1]. Overall, KLK5 serves as a central regulatory node in skin proteolytic cascades, offering mechanistic insight and intervention points for inflammatory dermatological conditions.

KLK5 Related Products (4):

Cat. No. Product Name Effect Purity
  • HY-148949A
    Kallikrein 5-IN-2 TFA
    		Inhibitor 99.53%
    Kallikrein 5-IN-2 TFA is the TFA salt form of Kallikrein 5-IN-2 (HY-148949). Kallikrein 5-IN-2 TFA is a selective inhibitor for kallikrein 5 (KLK5) with pIC50 of 7.1. Kallikrein 5-IN-2 TFA is non-phototoxic (100 μg/mL) and non-irritant. Kallikrein 5-IN-2 is stable at pH 4-pH 8 under non-oxidative condition. Kallikrein 5-IN-2 is potent in ameliorating the Netherton syndrome.
  • HY-P11840
    KLK5-IN-1
    		Inhibitor
    KLK5-IN-1 is a selective kallikrein 5 (KLK5) inhibitor with an IC50 of 14 nM and a Ki of 11 nM. KLK5-IN-1 reduces KLK5-mediated PAR2-dependent calcium mobilization. KLK5-IN-1 improves epithelial barrier integrity. KLK5-IN-1 can be used in research related to atopic dermatitis and Netherton syndrome.
  • HY-150085
    GSK951
    		Inhibitor
    GSK951 is a potent and selective Kallikrein-5 (KLK5) inhibitor amenable to epidermal delivery. GSK951 shows an IC50 of 250 pM for KLK5 and greater than 100-fold selectivity over KLK7 and KLK14. GSK951 can reduce transepidermal water loss, and decrease proinflammatory cytokine expression. GSK951 can be used for the researches of inflammation and immunology, such as Netherton syndrome.
  • HY-124714
    DKFZ-251
    		Inhibitor
    DKFZ-251 is a kininogenase-related peptidase KLK6 inhibitor (IC50=0.47 μM), and also exhibits certain inhibitory activity against KLK5 and KLK7 (IC50 values are 1.1 nM and 73 nM, respectively). DKFZ-251 transiently acylates the catalytic serine of KLK6 to form a long-lived acyl-enzyme complex that inhibits enzyme function. DKFZ-251 is a phenotypic modulator that alters cell proliferation capacity and regulates epithelial-mesenchymal transition (EMT). DKFZ-251 can be used in research related to head and neck cancer.