Novel Human Full-Thickness Three-Dimensional Nonkeratinized Mucous Membrane Model for Pharmacological Studies in Wound Healing.

INTRODUCTION: Efforts are increasingly aiming to develop in vitro models that can provide effective alternatives to in vivo experiments. The main aim of this study was the establishment of an in vitro model of the nonkeratinized mucous membrane that can be used as a standardized tool to evaluate biological and therapeutic effects of pharmaceuticals for mucosal wound healing. METHODS: We established a full-thickness in vitro model of the nonkeratinized mucous membrane. While histological examination was performed to assess morphological characteristics, we utilized gene expression profiling using microarray and qRT-PCR analyses to identify molecular effects of treatment with a dexpanthenol-containing ointment after laser wounding. RESULTS: Performing histological and immunofluorescence analyses we proved that our model mimics the two distinctive layers of the mucous membrane - the stratified squamous epithelium and the lamina propria. We used this model to investigate molecular effects of a dexpanthenol-containing ointment that is commonly used for the wound treatment of mucous membranes. For that purpose, our model exhibits a unique feature in that dexpanthenol and proliferation-enhancing additives that may interfere with our studies are not required for the maintenance of the model culture. After setting standardized lesions with a nonsequential fractional ultrapulsed CO2 laser, topical treatment with the dexpanthenol-containing ointment enhanced wound closure in the model compared to placebo and untreated controls. Furthermore, microarray analysis revealed that the treatment of the laser-wounded model with the dexpanthenol-containing ointment evoked an upregulated expression of various genes related to accelerated wound healing. CONCLUSION: Overall, we verified that this novel mucous membrane model can be utilized in future to monitor ex vivo effects of various topical therapies on mucosa morphology, physiology, and gene expression. Our findings confirm the potential of the model as an in vitro tool for the replacement of pharmacological in vivo studies regarding mucosal wound healing.

Prospective, Randomized Study on the Efficacy and Safety of Local UV-Free Blue Light Treatment of Eczema.

BACKGROUND: Blue light was shown to reduce the activation of T cells and modulate cytokine release in vitro. Therefore, we investigated the efficacy of blue light in the treatment of eczema. METHODS: A sample of 21 patients with mild to moderate eczema were locally treated with blue LED light (light-emitting diode, emission maximum: 453 nm). They received light treatment 3 times per week for 4 weeks. A contralateral control lesion remained untreated. RESULTS: A total of 20 patients completed the trial with a compliance rate of 100%. The blue light treatment was safe with no adverse events and no side effects. The primary end point change from baseline in the mean sum score of the local Eczema Severity Index (local ESI) was more pronounced for the treated area than for the control area (-1.9 ± 2.02 vs. -1.3 ± 2.24). The treatment difference was statistically significant (p = 0.0152, paired t test, two-sided). CONCLUSION: In this study UV-free blue light was safe and effective in the reduction of eczema lesions.

Prospective Randomized Long-Term Study on the Efficacy and Safety of UV-Free Blue Light for Treating Mild Psoriasis Vulgaris.

BACKGROUND: Blue light irradiation reduces the proliferation of keratinocytes and modulates T-cell immune response in vitro and has been shown to reduce the severity of psoriasis vulgaris (Pv) in two clinical trials. OBJECTIVE: Evaluation of safety and efficacy of long-term UV-free blue light treatment at home for mild Pv. METHODS: Forty-seven patients with mild Pv were randomized for receiving high-intensity blue light treatment (HI: 453 nm LED, 200 mW/cm(2), n = 24) and low-intensity treatment (LI: 453 nm LED, 100 mW/cm(2), n = 23) of one Pv plaque for 12 weeks. A contralateral control plaque remained untreated. RESULTS: Patient compliance and satisfaction were high. The primary endpoint, change from baseline (CfB) of the Local Psoriasis Severity Index, revealed a significant improvement of the target compared to the control plaques (ΔCfB for the HI group: -0.92 ± 1.10, p = 0.0005; for the LI group: -0.74 ± 1.18, p = 0.0064). CONCLUSION: UV-free blue light home treatment is safe and improves Pv plaques.

Prospective randomized study on the efficacy of blue light in the treatment of psoriasis vulgaris.

BACKGROUND: Blue light has no known toxic effects on human skin, but reduces the proliferative capacity of keratinocytes in vitro. We therefore investigated the efficacy of blue light in the treatment of psoriasis vulgaris (PV). METHODS: Forty patients with mild to moderate PV and bilateral plaques were assigned to two groups. Group 1 (n = 20) received irradiation at home with blue light (light-emitting diode, LED, emission maximum: 420 nm) once daily for 4 weeks. In parallel, group 2 (n = 20) performed irradiations with another blue light device (LED emission maximum: 453 nm). The contralateral control plaques remained untreated in both groups. RESULTS: Thirty-seven patients completed the trial. The main study parameter, the difference of Local Psoriasis Severity Index (LPSI) scores of the irradiated plaques compared to the control plaques, showed statistically significant improvement after 4 weeks of treatment in both groups [group 1 (420 nm): n = 17, p = 0.04; group 2 (453 nm): n = 20, p = 0.04]. Accordingly, plaque status as assessed by both the physicians and the patients improved continuously during the 4 weeks of treatment and steadily declined thereafter. CONCLUSION: Blue light appears to be a promising treatment modality in PV that warrants further evaluation in larger studies.