The skin is the first line of defense of our body, and it is composed of the epidermis and dermis with diverse immune cells. Various in vitro models have been investigated to recapitulate the immunological functions of the skin and to model inflammatory skin diseases. The simplest model is a two-dimensional (2D) co-culture system, which helps understand the direct and indirect cellto-cell interactions between immune and structural cells; however, it has limitations when observing three-dimensional (3D) interactions or reproducing skin barriers. Conversely, 3D skin constructs can mimic the human skin characteristics in terms of epidermal and dermal structures, barrier functions, cell migration, and cell-to-cell interaction in the 3D space. Recently, as the importance of neuro-immune-cutaneous interactions in the inflammatory response is emerging, 3D skin constructs containing both immune cells and neurons are being developed. A microfluidic culture device called “skin-on-a-chip,” which simulates the structures and functions of the human skin with perfusion, was also developed to mimic immune cell migration through the vascular system. This review summarizes the in vitro skin models with immune components, focusing on two highly prevalent chronic inflammatory skin diseases: atopic dermatitis and psoriasis. The development of these models will be valuable in studying the pathophysiology of skin diseases and evaluating the efficacy and toxicity of new drugs.

The skin is the first line of defense of our body, and it is composed of the epidermis and dermis with diverse immune cells. Various in vitro models have been investigated to recapitulate the immunological functions of the skin and to model inflammatory skin diseases. The simplest model is a two-dimensional (2D) co-culture system, which helps understand the direct and indirect cellto-cell interactions between immune and structural cells; however, it has limitations when observing three-dimensional (3D) interactions or reproducing skin barriers. Conversely, 3D skin constructs can mimic the human skin characteristics in terms of epidermal and dermal structures, barrier functions, cell migration, and cell-to-cell interaction in the 3D space. Recently, as the importance of neuro-immune-cutaneous interactions in the inflammatory response is emerging, 3D skin constructs containing both immune cells and neurons are being developed. A microfluidic culture device called “skin-on-a-chip,” which simulates the structures and functions of the human skin with perfusion, was also developed to mimic immune cell migration through the vascular system. This review summarizes the in vitro skin models with immune components, focusing on two highly prevalent chronic inflammatory skin diseases: atopic dermatitis and psoriasis. The development of these models will be valuable in studying the pathophysiology of skin diseases and evaluating the efficacy and toxicity of new drugs.

Sarcoidosis is a multisystem granulomatous disease of unknown etiology. A range of factors including tuberculous infection, beryllium exposure, and cold climate have been implicated in the pathogenesis of the condition. A 45-year-old woman presented with a 4-month history of an asymptomatic eyelid swelling and multiple erythematous papules on the neck. Histological examination of the neck, orbital soft tissue, and lacrimal gland was consistent with sarcoidosis. Ziehl−Neelsen stains and polymerase chain reactions (PCRs) for tuberculosis on the skin biopsy specimens were negative. However, the orbital soft tissue specimen was positive for non-tuberculous mycobacteria (NTM) PCR. The patient was finally diagnosed with sarcoidosis associated with NTM. Treatment with systemic steroid and hydroxychloroquine was started, resulting in an improvement of skin lesions. We herein report a case of sarcoidosis associated with NTM infection with review of the literature, as only little is known regarding the role of mycobacteria in sarcoidosis.

BACKGROUND: Growth factors play important roles in wound healing. However, the evidence for the effects of growth factors on post-thyroidectomy scars is limited. OBJECTIVE: We performed a prospective study to assess the preventive and therapeutic effect of a multi-growth factor (MGF)-containing cream on post-thyroidectomy scars. METHODS: Twenty-one patients with thyroidectomy scars applied MGF cream twice a day. We assessed the changes in erythema, pigmentation, skin elasticity, and skin hydration status using the erythema index, melanin index, cutometer, and corneometer, respectively. In addition, Vancouver scar scale (VSS) and patient satisfaction were assessed at 10 days after surgery (baseline), 2 weeks, 6 weeks, and 12 weeks after baseline. RESULTS: The mean total VSS scores were significantly lower at 6 weeks (3.24±1.51 vs. 1.91±1.38) and 12 weeks (3.24±1.51 vs. 1.71±1.59) compared to the baseline. The degree of pigmentation was significantly lower at 12 weeks compared to the baseline, and the skin elasticity, and the skin hydration status were significantly higher at 12 weeks compared to the baseline. Over 85% of the patients were satisfied with the use of MGF cream without any adverse effect. CONCLUSION: MGF cream might have additive or supportive effect for scar formation after thyroidectomy.
Cicatrix* ; Elasticity ; Erythema ; Humans ; Intercellular Signaling Peptides and Proteins ; Melanins ; Patient Satisfaction ; Pigmentation ; Prospective Studies ; Skin ; Skin Pigmentation ; Thyroidectomy ; Wound Healing

BACKGROUND: Biodegradable microneedle technology is a recently developed method to deliver medical and pharmaceutical medications into the skin, and is expected to yield better treatment results than topical application methods. OBJECTIVE: To evaluate the efficacy of hyaluronic acid (HA)-based microneedle patches and epidermal growth factor (EGF)-containing microneedle patches on periorbital wrinkle improvement. METHODS: A 20-week randomized, double-blind study was performed. Twenty-five Korean patients with periorbital wrinkles and a wrinkle severity rating scale (WSRS) score above 2 were enrolled into the study. The patients completed the study using the two different types of patches on each side of the designated periorbital wrinkles area every other day for 8 weeks. Patients were requested for an additional 12-week follow up. Wrinkle improvements were assessed by WSRS score, subjective patient satisfaction score, and imaging analysis using the visiometer, corneometer, cutometer, and mexameter, respectively (Courage&Khazaka, Cologne, Germany). RESULTS: Both the HA-based microneedle patch and EGF-containing HA-based microneedle patch had positive effects on WSRS score, patient satisfaction levels, and corneometer result with statistically significant differences. No significant side effects were noticed. CONCLUSION: With respect to efficacy, no statistical difference between the two groups were noted, indicating that the anti-wrinkle effects of the microneedle patch may solely be due to the HA rather than the EGF.
Double-Blind Method ; Epidermal Growth Factor ; Follow-Up Studies ; Humans ; Hyaluronic Acid ; Patient Satisfaction ; Skin

A giant cell tumor of tendon sheath is a slow growing benign soft tissue tumor that is known by a variety of names including fibrous histiocytoma of tendon sheath and fibrous xanthoma of the synovium. Clinically, it presents as a 1~3 cm firm, non-mobile, painless, nontender mass, and mostly occurs at interphalangeal joints of fingers. It shows female predominance and can occur at any age, but it is most common between the third and fifth decades and is rare in children. We now report the case of a 10-year-old girl with a giant cell tumor of tendon sheath on the toe.
Child ; Female ; Fingers ; Giant Cell Tumors ; Giant Cells ; Histiocytoma, Benign Fibrous ; Humans ; Joints ; Synovial Membrane ; Tendons ; Toes ; Xanthomatosis

Background: Psoriasis is a chronic T17 cell-driven immune-mediated inflammatory disease. However, patients with psoriasis may have elevated total serum immunoglobulin E (IgE) levels, which is a hallmark of Th2 inflammation.In previous case reports, psoriasis patients with elevated total serum IgE levels did not respond well to treatment or had exacerbated eczema lesions. Objective: We sought to investigate the clinical characteristics of psoriasis patients with elevated total serum IgE levels. Methods: This is a retrospective chart review of 130 patients with psoriasis who were tested for total serum IgE levels from November 1, 2009, to October 31, 2019. We compared the demographics, clinical characteristics, disease severity, and treatment regimen for each elevated IgE group (＞214 U/mL) and normal IgE group (≤214 U/mL). Results: Among 130 patients with psoriasis, 41 (31.5%) had elevated total serum IgE levels. Elevated total serum IgE levels were positively associated with the severity of disease; psoriasis lesions including those on the scalp, hands, feet, and flexures, which are difficult to treat, were observed to be significantly higher in patients with elevated total serum IgE levels. There was no correlation between age, sex, disease duration, or presence of pruritus and total serum IgE levels. Conclusion This study identified the clinical characteristics of psoriasis patients with elevated total serum IgE levels in Korea.

Background: Rosacea is a common skin disease associated with increased expression of cathelicidin, kallikrein 5 (KLK5), toll-like receptor (TLR) 2, and abnormal barrier function. Recently, it was reported that hyaluronan (HA) could influence immune function via various receptors and HA oligosaccharides (oligo-HAs) could suppress TLR-dependent cytokine expression. Objective: We investigated if oligo-HAs could influence on inflammation and epidermal barrier induced by LL-37, which had a major role in rosacea. Methods: We cultured normal human keratinocytes and treated them with LL-37 and oligo-HAs or the LL-37 alone. A rosacea-like BALB/c mouse model injected with LL-37 was used to determine the role of oligo-HAs in rosacea in vivo. Results: Interleukin-8 (IL-8) and tumor necrosis factor (TNF)-α release was suppressed when keratinocytes were co-treated with oligo- HAs and LL-37 compared with keratinocytes treated with LL-37 only. Treatment with oligo-HAs resulted in decreased transepidermal water loss as well as improved redness. Decreased inflammatory cell infiltration, IL-17A and KLK5 expression and increased CD44 and filaggrin expression were also noted. Conclusion Our findings suggest that oligo-HA improves rosacea-like phenotype through anti-inflammatory and epidermal barrier improving effect.