Unique features of human cathelicidinLL‐37

Abstract

Cathelicidins are antimicrobial peptides produced by humans and animals in response to various pathogenic microbes. This review intends to provide a brief overview of the expression, structure, properties and function of human cathelicidin LL-37 which may be a therapeutic agent against a variety of bacterial and viral diseases, cancers, and hard-to-heal wounds. Cathelicidins act as a primary defense against bacteria and other pathogens in the case of inflammation. They are able to kill bacteria and fungi, inhibit and destroy bacterial biofilms, and possess antiviral and antiparasitics properties. They can also play a role in angiogenesis, wound healing, and the regulation of apoptosis. The host defense peptide LL-37 has emerged as a novel modulator of tumor growth and metastasis in carcinogenesis of various types of cancers. LL-37 is an antimicrobial peptide able of inducing various effects. It acts as an anti- and pro- inflammatory factor. Cathelicidins are able to directly and selectively destroy membranes of various microbes and cancer cells, but they do not attack normal cells. The role of cathelicidins in cancer is double-sided. They play an important role in killing cancer cells and may provide a new possibility for the development of cancer therapeutics. However, they also can participate in carcinogenesis. Due to its activity spectrum LL-37 could be applied in pharmacotherapy. Cathelicidin peptides could serve as a template for the development of modern anti-microbial and anti-viral drugs. LL-37 is an excellent candidate to develop into therapeutics for infected wounds.

Cathelicidin PR-39 peptide inhibits hypoxia/reperfusion-induced kidney cell apoptosis by suppression of the endoplasmic reticulum-stress pathway

“…Thus, as an alternative member of the cathelin family, LL-37 has been highly expressed in human psoriatic keratinocytes [47]. As the human homolog to PR-39, LL-37 peptides not only possess a broad antibacterial spectrum, but also have angiogenesis and anti-apoptotic effects [48,49]. Vázquez-Sánchez et al [50] reported that the anti-apoptotic effect of LL-37 is also mediated through the up-regulation of c-IAP-2 via the caspase-3 pathway.…”

Vitamin D and Lung Infection

“…The antibacterial peptide cathelicidin is induced by the active form of vitamin D [1,25(OH) 2 Cathelicidin has been shown to have direct antibacterial, antifungal, antiviral, and immunoregulatory properties when added to infected cells and cultures in vitro (6). It kills bacteria by disrupting bacterial membranes and blocks viral entry by interacting with viral proteins, suppressing viral entry and/or replication (6).…”

“…It kills bacteria by disrupting bacterial membranes and blocks viral entry by interacting with viral proteins, suppressing viral entry and/or replication (6). Cathelicidin can both inhibit the growth of and increase the virulence of P. aeruginosa via mutation, resulting in chronic infection (7).…”

“…Cathelicidin can both inhibit the growth of and increase the virulence of P. aeruginosa via mutation, resulting in chronic infection (7). In addition, it modulates the host immune response by inducing production of chemoattractants and cytokines (6). Cathelicidin may also be associated with immune-mediated diseases like rheumatoid arthritis and psoriasis (6).…”

“…In addition, it modulates the host immune response by inducing production of chemoattractants and cytokines (6). Cathelicidin may also be associated with immune-mediated diseases like rheumatoid arthritis and psoriasis (6). Although the contribution of cathelicidin to the host response to different pathogens in vivo is still not well understood, it could be beneficial for both microbial clearance and immune regulation but detrimental if it induces pathogen mutation or contributes to immune system-mediated disease.…”