Increased serine protease activity and cathelicidin promotes skin inflammation in rosacea.

Acne rosacea is an inflammatory skin disease that affects 3% of the US population over 30 years of age and is characterized by erythema, papulopustules and telangiectasia. The etiology of this disorder is unknown, although symptoms are exacerbated by factors that trigger innate immune responses, such as the release of cathelicidin antimicrobial peptides. Here we show that individuals with rosacea express abnormally high levels of cathelicidin in their facial skin and that the proteolytically processed forms of cathelicidin peptides found in rosacea are different from those present in normal individuals. These cathelicidin peptides are a result of a post-translational processing abnormality associated with an increase in stratum corneum tryptic enzyme (SCTE) in the epidermis. In mice, injection of the cathelicidin peptides found in rosacea, addition of SCTE, and increasing protease activity by targeted deletion of the serine protease inhibitor gene Spink5 each increases inflammation in mouse skin. The role of cathelicidin in enabling SCTE-mediated inflammation is verified in mice with a targeted deletion of Camp, the gene encoding cathelicidin. These findings confirm the role of cathelicidin in skin inflammatory responses and suggest an explanation for the pathogenesis of rosacea by demonstrating that an exacerbated innate immune response can reproduce elements of this disease.

Psoriatic keratinocytes are resistant to tumor necrosis factor alpha's induction of mRNA for the NMDA-R2C subunit.

Psoriatic individuals demonstrate accelerated healing and the Koebner phenomenon, suggesting that psoriatic proliferation of keratinocytes is not inhibited appropriately after skin injury. Serial analysis of gene expression in TNFα-exposed keratinocytes shows the greatest alteration in expression of NMDA-R2C. Expression of the NMDA receptor is altered in diseased skin containing TNFα, and TNFα plays a prominent role in psoriasis. An abnormality in induction of NMDA-R2C by TNFα in psoriatic keratinocytes may explain their lack of growth inhibition. We compared the capacity of TNFα to induce expression of NMDA-R2C in normal and psoriatic (involved and uninvolved) keratinocytes in vitro. After 72 h of incubation with TNFα, normal keratinocytes demonstrated a significant induction of NMDA-R2C mRNA compared with control cultures, whereas psoriatic keratinocytes showed no induction. In an in vitro model of wounding (scratches on monolayers), TNFα inhibited migration/proliferation of keratinocytes only at the edge of NMDA-R2C expressing wounded monolayers of normal keratinocytes.

Use of gelatin sponges in Mohs micrographic surgery defects and staged melanoma excisions: a novel approach to secondary wound healing.

BACKGROUND/AIMS: surgical closure or reconstruction is commonly used to treat wounds generated by Mohs micrographic surgeries (MMS) and staged melanoma excisions, which may result in contractures and scarring. The authors' objective was to determine the value of using gelatin sponges to promote secondary intention healing for surgical defects after MMS and staged melanoma excisions. METHODS: sixty-four surgeries from 54 predominantly elderly patients (median age=76 years) were treated with gelatin sponges to promote healing by secondary intention in this prospective investigation. Patients rated their satisfaction with outcomes on a scale of 1 (highly dissatisfied) to 5 (highly satisfied). RESULTS: in all patients, the wounds healed within four to 16 weeks (median=five weeks). Forty-five patients were highly satisfied with their results (mean score=4.9). CONCLUSION: healing by secondary intention using gelatin sponges was associated with improved hemostasis, excellent cosmesis and a high level of patient satisfaction.

The Relationship of Wound Healing with Psoriasis and Multiple Sclerosis.

Significance: Better understanding of wound healing could lead to improved treatment(s) of multiple sclerosis (MS) and psoriasis (Pso). Recent Advances: New concepts in the events of wound healing, such as the roles of the innate and adaptive immune systems, have generated targets for treating these debilitating diseases. Innovation: That in MS and Pso defective wound healing is responsible for the diseases' progression has not been hypothesized to date. Conclusion: Impaired initiation of wound repair by oligodendrocyte precursor cells or oligodendrocytes may play a role in MS, and a lack of inhibition of the proliferative phase in wound healing may explain the pathophysiology involved in Pso.

Bilateral comparison of the efficacy and tolerability of 3% diclofenac sodium gel and 5% 5-fluorouracil cream in the treatment of actinic keratoses of the face and scalp.

Actinic keratoses (AKs) are a common precancerous condition and are said to account for 14% of visits to dermatologists in the US each year. Along with cryotherapy, topical treatments are a mainstay of therapy for these lesions. One of the potential benefits of topical therapy is less pain and irritation as compared to cryotherapy. Additionally, topical therapies have a perceived benefit of treating subclinical lesions along with clinically evident keratoses. We conducted a bilateral comparison study of the efficacy and tolerability of diclofenac 3% gel used for 90 days and 5% fluorouracil cream used for 28 days in thirty patients with AK of the face and scalp. The diclofenac gel and 5-fluorouracil cream each demonstrated substantial efficacy in the number of lesions cleared and the proportion of patients with significant lesion clearing. In most patients, diclofenac induced only mild signs of inflammation compared to 5-fluoruracil, despite a longer treatment period. A greater number of patients expressed significant satisfaction with diclofenac gel compared to the 5-fluorouracil cream.

Migration studies and histology of injectable microspheres of different sizes in mice.

Injectable dermal filler materials consist of either fluids, biological fragments, or suspensions of particles or microspheres. Particles and microspheres are said to "migrate," but migration can occur only when they are injected into blood vessels. To evaluate biocompatibility and transport, five nonresorbable polymethylmethacrylate microspheres of various sizes, suspended in different carriers, as well as resorbable polylactic acid and dextran microspheres were injected subcutaneously into mice. The five implantation sites were the right cheek, right axilla, right groin, urethra, and the right quadriceps muscle of the thigh. These sites were excised along with the local lymph nodes, lungs, liver, and spleen at 1, 3, 6, and 9 months after injection. Polymethylmethacrylate microspheres of 4 microm and 8 microm were phagocytosed but not transported to lymph nodes or distant organs. Larger microspheres of 20, 40, and 100 microm were encapsulated by connective tissue, macrophages, and giant cells. Polylactic acid microspheres caused a mild inflammatory response and had disappeared at 6 months. Dextran microspheres caused a pronounced foreign-body reaction and were phagocytosed at 9 months. The extremely large carbon-coated spheres of 200 to 500 microm in diameter "migrated" up to 1 cm from the implantation site. With the exception of an erroneous intravenous injection, no migration or transportation of any of the injected microspheres to lymph nodes or filter organs was seen. Obviously, the collagen glue released no microspheres. After subdermal injection, the collagen carrier substance kept the microspheres apart as a scaffold for tissue ingrowth, whereas all other carrier substances, such as gelatin, hyaluronic acid, or alginate, separated soon after injection, thereby causing agglomeration of the microspheres.

Acrosyringium is the main site of the vesicle/pustule formation in palmoplantar pustulosis.

Pustulosis 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.

Phagocytosis of different particulate dermal filler substances by human macrophages and skin cells.

BACKGROUND: Foreign substances have been introduced into the human body with varying degrees of success. Polymethylmethacrylate (PMMA) microspheres of different sizes recently have been manufactured for use as a filler substances in the skin and other organs. OBJECTIVE: To establish whether the size of PMMA microspheres determines whether various cell types initiate phagocytosis. METHODS: The capacity of three different cell lines-U-937 cells, XS 106 and XS 52 Langerhans cells, and HaCaT keratinocytes-to phagocytose microspheres of varying sizes was examined using light and confocal microscopy as well as fluorescence-activated cell sorter (FACS) analysis. Tumor necrosis factor (TNF)-alpha secretion was also determined. RESULTS: The U-937 cells, keratinocytes, and Langerhans cells could phagocytose PMMA particles of 20 microm or smaller. Microspheres larger than 20 microm were not ingested by any of the cells. CONCLUSION: Microspheres larger than 20 microm have a lower likelihood of being phagocytosed. Thus this study suggests that microspheres 40-50 microm in diameter are less likely to initiate an inflammatory reaction when injected into the dermis and subdermis as a filler substance. On the other hand, microparticles made of silicone and polymethacrylate were phagocytosed, possibly because of their different structure.

Dermatan sulfate proteoglycan and glycosaminoglycan synthesis is induced in fibroblasts by transfer to a three-dimensional extracellular environment.

Composition and architecture of the extracellular matrix dictate cell behavior. Proteoglycans bind multiple components of the extracellular matrix by serving as important regulators of cell behavior. Given the influence of culture architecture on cell function, we investigated whether switching NIH3T3 fibroblasts from growth on type 1 collagen in monolayer to a collagen gel might influence dermatan sulfate expression. Immunofluorescent staining, immunoblot, and Western blot demonstrated an induction in decorin expression in cells switched to collagen gels. This induction was associated with a 40-fold increase in decorin transcript expression determined by quantitative real time PCR. Disaccharide analysis of extracted glycosaminoglycans from collagen gels showed an increase in total glycosaminoglycan and in the ratio of chondroitin sulfate to heparan sulfate compared with monolayer culture. The ratio of chondroitin sulfate to heparan sulfate likewise increased on syndecan-1 from gel culture. Digestion with chondroitinase B showed that this induced chondroitin sulfate was dermatan sulfate. Syndecan-1 extracted from wounded mouse skin also displayed an increase in dermatan sulfate synthesis compared with unwounded skin. Furthermore, glycosaminoglycans from collagen gel culture activated keratinocyte growth factor, whereas glycosaminoglycans from monolayer culture lacked this ability. These findings suggest that regulation of dermatan sulfate and dermatan sulfate proteoglycan is dependent on extracellular matrix architecture. The ability of collagen gel culture to mimic better the in vivo dermal environment may be due in part to this influence on dermatan sulfate and dermatan sulfate proteoglycan synthesis.