Cathelicidin antimicrobial peptides are expressed in salivary glands and saliva

International & American Associations for Dental Research, Murakami, M. ; Ohtake, T. ; Dorshner, RA. ; Gallo, RL., Journal of dental research, 81(12), 2002, 845-850. publisherThe expression of antimicrobial peptides at epithelial surfaces such as skin, lung, and intestine is thought to provide protection against infection. Cathelicidin antimicrobial peptides are essential for the protection of skin against invasive bacterial infection. To determine if cathelicidins are also present in the oral cavity, we examined the expression of both mRNA and protein in mice and human saliva. The murine cathelicidin (CRAMP) was detected in the adult by reverse-transcription/polymerase chain-reaction (RT-PCR), and in embryonic, newborn, and adult tissues by in situ hybridization and immunohistochemistry. CRAMP mRNA and protein were localized to the salivary glands, specifically in acinar cells of the submandibular gland and palatine minor glands, as well as in lingual epithelium and palatal mucosa. In man, the human cathelicidin LL-37 was detected in human saliva by Western blotting. These results indicate that cathelicidins are present in the salivary system, in some oral epithelia, and in saliva, contributing to broad-spectrum defense of the oral cavity

掌蹠膿疱症発症メカニズムの解明（及び治療法の開発）

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Expression and secretion of cathelicidin antimicrobial peptides in murine mammary glands and human milk

This is a non-final version of an article published in final form in Shuke, MURAKAMI, MASAMOTO ; DORSCHNER, ROBERT A .; STERN, LAUREN J. ; LIN, KENNETH H. ; GALLO, RICHARD L., Expression and secretion of cathelicidin antimicrobial peptides in murine mammary glands and human milk,Pediatric research 57(1), 2005, pp. 10-15 authorMammalian milk possesses inherent antimicrobial properties that have been attributed to several diverse molecules. Recently, antimicrobial peptides that belong to the cathelicidin gene family have been found to be important to the mammalian immune response. This antimicrobial is expressed in several tissues and increased in neonatal skin, possibly to compensate for an immature adaptive immune response. We hypothesized that the mammary gland could produce and secrete cathelicidin onto the epithelial surface and into milk. Human cathelicidin hCAP18/LL-37 mRNA was detected in human milk cells by PCR. Quantitative real-time PCR demonstrated an increase in relative expression levels at 30 and 60 d after parturition. Immunohistochemistry of mouse breast tissue identified the murine cathelicidin-related antimicrobial peptide in lobuloacinar and ductules. Western blot analysis of human milk showed that LL-37 was secreted and present in the mature peptide form. The antimicrobial activity of LL-37 against Staphylococcus aureus, group A Streptococcus, and enteroinvasive Escherichia coli O29 in the human milk ionic environment was confirmed by solution colony-forming assay using synthetic peptide. These results indicate that cathelicidin is secreted in mammary gland and human milk, has antimicrobial activity against both Gram-positive and Gram-negative bacteria, and can contribute to the anti-infectious properties of milk

Nuclear IL-33 Plays an Important Role in EGFR-Mediated Keratinocyte Migration by Regulating the Activation of Signal Transducer and Activator of Transcription 3 and NF-κB

Nuclear IL-33 levels are high at the epidermal edges of skin wounds and facilitate wound healing. However, IL-33−mediated regulation of keratinocyte (KC) biology during wound healing remains poorly understood. During skin-wound healing, KC migration and re-epithelialization are mediated predominantly by EGFR signaling activation and depend on the function of signal transducer and activator of transcription 3 (STAT3). We found that migrating KCs at the leading edges of mouse skin wounds exhibited concomitant induction and nuclear colocalization of IL-33 and phosphorylated STAT3. In cultured human KCs, activation of EGFR signaling caused rapid elevation of nuclear IL-33, which directly interacts with phosphorylated STAT3, promoting STAT3 activation. In vitro KC migration and wound-healing assays revealed that high nuclear IL-33 levels were required for KC migration and wound closure. KC mobility associated with a lack of suprabasal epidermal keratins and extracellular matrix degradation mediated by matrix metalloproteinases (MMPs) control cell migration at the intracellular and extracellular levels, respectively. In EGFR-activated KCs, nuclear IL-33 mediated keratin 1 and 10 downregulation and MMP9 upregulation by promoting STAT3 activation and limited MMP1, MMP3, and MMP10 induction by suppressing NF-κB transactivation. Thus, epidermal nuclear IL-33 is involved in KC migration and wound closure by regulating the STAT3 and NF-κB pathways

Lamellar Granule Secretion Starts before the Establishment of Tight Junction Barrier for Paracellular Tracers in Mammalian Epidermis

Defects in epidermal barrier function and/or vesicular transport underlie severe skin diseases including ichthyosis and atopic dermatitis. Tight junctions (TJs) form a single layered network in simple epithelia. TJs are important for both barrier functions and vesicular transport. Epidermis is stratified epithelia and lamellar granules (LGs) are secreted from the stratum granulosum (SG) in a sequential manner. Previously, continuous TJs and paracellular permeability barriers were found in the second layer (SG2) of SG in mice, but their fate and correlation with LG secretion have been poorly understood. We studied epidermal TJ-related structures in humans and in mice and found occludin/ZO-1 immunoreactive multilayered networks spanning the first layer of SG (SG1) and SG2. Paracellular penetration tracer passed through some TJs in SG2, but not in SG1. LG secretion into the paracellular tracer positive spaces started below the level of TJs of SG1. Our study suggests that LGsecretion starts before the establishment of TJ barrier in the mammalian epidermis

Acrosyringium Is the Main Site of the Vesicle/Pustule Formation in Palmoplantar Pustulosis

http://dx.doi.org/10.1038/jid.2010.87 © 2010 Society for Investigative DermatologyPustulosis palmaris et plantaris or palmoplantar pustulosis (PPP) is a refractory pustular eruption on the palms and soles with unknown etiology. Numerous eccrine sweat pores exist on the palms and soles, suggesting the involvement of eccrine sweating in the pathogenesis of PPP. To the best of our knowledge, however, no definite abnormality in sweating has been documented in PPP. Accordingly, we analyzed the eccrine sweat duct involvement in the mechanism of vesicle formation in PPP. Dermatoscopy showed that PPP vesicles are located on the top of the ridges but not in the furrows. The sweat secretion in the lesional area was much lower than that in the nonlesional area, with or without pain stimulation to induce sweating. Immunostaining of horizontal sections of the lesions using antibodies against gross cystic disease fluid protein-15 (GCDFP-15) and epithelial membrane antigen (EMA) showed that these markers were localized in the cells lining the intraepidermal vesicles. Although the sweat antimicrobial peptides, dermcidin and human cathelicidin antimicrobial peptide 18 (hCAP-18)/LL-37, were detected in the fluid of the vesicles/pustules, neither dermcidin nor hCAP-18/LL-37 were overexpressed by neighboring keratinocytes. These findings suggest that the acrosyringium may be involved as the main site of the vesicle formation in the pathomechanism of PPP