Expression pattern of tissue-resident memory T cells in cutaneous lupus erythematosus.

BACKGROUND: Tissue resident memory T cells (TRMs) persist long-term in peripheral tissues without recirculation, triggering an immediate protective inflammatory state upon the re-recognition of the antigen. Despite evidence incriminating the dysregulation of TRMs in autoimmune diseases, few studies have examined their expression in cutaneous lupus erythematosus (CLE). OBJECTIVES: We aimed to examine whether there are differences among TRM populations in CLE depending on different clinical conditions, such as the CLE subtype or association with systemic lupus erythematosus, and to determine the effect of type I interferon (IFN) on the development of TRMs in CLE. METHODS: CLE disease activity was evaluated using the Cutaneous Lupus Erythematosus Disease Area and Severity Index. The expression of the TRM markers CD69 and CD103 in CLE lesions was evaluated by immunofluorescence. Flow cytometry was performed on peripheral blood mononuclear cells after IFNα treatment. RESULTS: The number of TRMs expressing either CD69 or CD103 was significantly higher in CLE lesions than in control skin; however, it was not significantly different between discoid lupus erythematosus and subacute CLE, or dependent on the presence of concomitant systemic lupus. Lesional severity was not correlated with an increase in TRMs in CLE. IFNα treatment induced a conspicuous increase in CD69 expression in skin-homing T cells, more profoundly in CD4+ T cells than in CD8+ T cells. CONCLUSIONS: Skin TRMs, either CD69 or CD103-positive cells, showed increased levels in the lesional skin of CLE, and IFNα increased the expression of CD69 in T cells.

Associations between ambient air pollution and medical care visits for atopic dermatitis.

BACKGROUND: Previous studies have reported numerous environmental factors for atopic dermatitis (AD), such as allergens and chemical stimulants. However, few studies have addressed the relationship between ambient air pollution and AD at a population level. OBJECTIVE: To evaluate the effect of air pollutants on medical care visits for AD and to identify susceptible populations. METHODS: In this time-series study conducted on 513,870 medical care visits for AD from 2012 to 2015 identified by reviewing national health insurance claim data in Incheon, Republic of Korea. Treating daily number of medical care visits for AD as a dependent variable, generalized additive models with Poisson distributions were constructed, which included air pollutant levels, ambient temperature, relative humidity, day of the week, national holiday, and season. Risks were expressed as relative risks (RR) with 95% confidence intervals (95% CIs) per interquartile range increase of each air pollutant. RESULTS: Higher levels of particulate matter of diameter ≤10 µm (PM10) (RR, 1.009; 95% CI, 1.007-1.012), ozone (1.028; 1.023-1.033), and sulfur dioxide (1.033; 1.030-1.037) were significantly associated with increased risk of medical care visits for AD on same days. In all age and sex groups, ozone was associated with a significantly higher risk of medical care visits, with the greatest risk among 13- to 18-year-old males (RR, 1.127; 95% CI, 1.095-1.159). CONCLUSION: This study suggests relationships of ambient PM10, ozone, and sulfur dioxide levels with medical care visits for AD.

Lysophosphatidic Acid Mediates Imiquimod-Induced Psoriasis-like Symptoms by Promoting Keratinocyte Proliferation through LPAR1/ROCK2/PI3K/AKT Signaling Pathway.

Psoriasis is a chronic inflammatory skin disease. Recently, lysophosphatidic acid (LPA)/LPAR5 signaling has been reported to be involved in both NLRP3 inflammasome activation in macrophages and keratinocyte activation to produce inflammatory cytokines, contributing to psoriasis pathogenesis. However, the effect and molecular mechanisms of LPA/LPAR signaling in keratinocyte proliferation in psoriasis remain unclear. In this study, we investigated the effects of LPAR1/3 inhibition on imiquimod (IMQ)-induced psoriasis-like mice. Treatment with the LPAR1/3 antagonist, ki16425, alleviated skin symptoms in IMQ-induced psoriasis-like mouse models and decreased keratinocyte proliferation in the lesion. It also decreased LPA-induced cell proliferation and cell cycle progression via increased cyclin A2, cyclin D1, cyclin-dependent kinase (CDK)2, and CDK4 expression and decreased p27Kip1 expression in HaCaT cells. LPAR1 knockdown in HaCaT cells reduced LPA-induced proliferation, suppressed cyclin A2 and CDK2 expression, and restored p27Kip1 expression. LPA increased Rho-associated protein kinase 2 (ROCK2) expression and PI3K/AKT activation; moreover, the pharmacological inhibition of ROCK2 and PI3K/AKT signaling suppressed LPA-induced cell cycle progression. In conclusion, we demonstrated that LPAR1/3 antagonist alleviates IMQ-induced psoriasis-like symptoms in mice, and in particular, LPAR1 signaling is involved in cell cycle progression via ROCK2/PI3K/AKT pathways in keratinocytes.

Stem Cell Secretome and Its Effect on Cellular Mechanisms Relevant to Wound Healing.

Stem cells introduced to site of injury primarily act via indirect paracrine effects rather than direct cell replacement of damaged cells. This gives rise to understanding the stem cell secretome. In this study, in vitro studies demonstrate that the secretome activates the PI3K/Akt or FAK/ERK1/2 signaling cascades and subsequently enhances the proliferative and migratory abilities of various types of skin cells, such as fibroblasts, keratinocytes, and vascular epithelial cells, ultimately accelerating wound contraction. Indeed, inhibition of these signaling pathways with synthetic inhibitors resulted in the disruption of secretome-induced beneficial effects on various skin cells. In addition, major components of the stem cell secretome (EGF, basic FGF, and HGF) may be responsible for the acceleration of wound contraction. Stimulatory effects of these three prominent factors on wound contraction are achieved through the upregulation of PI3K/Akt or FAK/ERK1/2 activity. Overall, we lay the rationale for using the stem cell secretome in promoting wound contraction. In vivo wound healing studies are warranted to test the significance of our in vitro findings.

Cholesterol Clefts in Basal Cell Carcinoma: An Under-Recognized Association.

Cholesterol clefts have rarely been described in cutaneous tumors other than lipid-rich tumors. However, they seem to be a relatively common phenomenon in basal cell carcinoma (BCC). This study was undertaken to determine the frequency of cholesterol cleft deposition in BCCs, and to identify associated histopathologic and clinical features. Twenty-eight of 249 BCC cases reviewed showed features of cholesterol cleft. Mean disease duration in those with cholesterol cleft was significantly longer than in those without cholesterol cleft (5.58 vs. 3.29 years, respectively; P = 0.013). Sex and age distributions, and average tumor longest diameter (11.6 vs. 9.41 mm) were no different for those with or without cholesterol clefts. The most common anatomical location was the nose in both those with and without cholesterol clefts. BCCs without cholesterol clefts more frequently involved the periauricular and perioral areas, and areas other than the head and neck, such as the trunk and lower extremities (P = 0.087). Histopathologic features of necrosis (26/28, 92.86%), keratinization (19/28, 67.86%), and pigment deposition (18/28, 64.29%) were found to be associated with cholesterol clefts. Cholesterol clefts were intratumorally located in 27/28 cases (96.43%), and stromally located in 2 cases (7.14%); intravascularly located cholesterol clefts were observed in no case. In conclusion, this study shows that cholesterol clefts are relatively common in BCC, and suggests that cholesterol crystal deposition could be associated with longer disease duration and microtrauma.

Bleomycin-Coated Microneedles for Treatment of Warts.

PURPOSE: Bleomycin-coated microneedles were devised for delivery of bleomycin into the sub-epidermal skin layer for the treatment of warts in order to provide patient convenience and reduce patient pain and fear. METHOD: Poly-lactic-acid (L-PLA) microneedles were fabricated by a molding process and then the tips were partially coated using a dip-coating method based on a microstructure well. The mechanical strength of the pre-coated polymer microneedles was observed by inserting them in porcine foot and back skin. The holes were stained with trypan blue and the mechanical failure of the microneedles was investigated using a scanning electron microscope (SEM). The initial distribution of a model drug using microneedles was compared with distribution by intralesional injection. The amount of drug leaked below the skin using microneedles was measured and compared with that leaked by intralesional injection. The pharmacokinetic properties of bleomycin-coated microneedles were studied. The bleomycin remaining on the coated microneedles after the in vivo pharmacokinetic study was measured. RESULTS: Bleomycin was successfully coated on the tips of L-PLA microneedles. More than 80% of the bleomycin dissolved into the skin in vitro within 15 min. L-PLA microneedles possessed sufficient mechanical strength to penetrate skin with a thick stratum corneum. Compared to intralesional injection, tip-coated microneedles were more effective in distributing a drug into the sub-epidermal skin layer. A pharmacokinetic study of bleomycin-coated microneedles showed 50 min of Tmax. CONCLUSIONS: Bleomycin-coated microneedles appeared to be a convenient and painless alternative to conventional intralesional injection of bleomycin. The microneedles delivered bleomycin into the targeted dermal layer regardless of body site. Bleomycin-coated microneedles therefore provide a suitable method for the treatment of warts.

TLR7-dependent eosinophil degranulation links psoriatic skin inflammation to small intestinal inflammatory changes in mice.

Recent evidence of gut microbiota dysbiosis in the context of psoriasis and the increased cooccurrence of inflammatory bowel disease and psoriasis suggest a close relationship between skin and gut immune responses. Using a mouse model of psoriasis induced by the Toll-like receptor (TLR) 7 ligand imiquimod, we found that psoriatic dermatitis was accompanied by inflammatory changes in the small intestine associated with eosinophil degranulation, which impaired intestinal barrier integrity. Inflammatory responses in the skin and small intestine were increased in mice prone to eosinophil degranulation. Caco-2 human intestinal epithelial cells were treated with media containing eosinophil granule proteins and exhibited signs of inflammation and damage. Imiquimod-induced skin and intestinal changes were attenuated in eosinophil-deficient mice, and this attenuation was counteracted by the transfer of eosinophils. Imiquimod levels and the distribution of eosinophils were positively correlated in the intestine. TLR7-deficient mice did not exhibit intestinal eosinophil degranulation but did exhibit attenuated inflammation in the skin and small intestine following imiquimod administration. These results suggest that TLR7-dependent bidirectional skin-to-gut communication occurs in psoriatic inflammation and that inflammatory changes in the intestine can accelerate psoriasis.

Analysis of the prevalence of and risk factors for atopic dermatitis using an ISAAC questionnaire in 8,750 Korean children.

BACKGROUND: Since 1995, epidemiologic studies of atopic disorders using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire have been performed in many countries, including the Republic of Korea. The prevalence, burden and risk factors of atopic dermatitis were surveyed in these studies, which helped to enhance their comparability among different areas and age groups, as well as to clarify the nature of atopic dermatitis and other atopic disorders. METHODS: From 21 facilities, 8,750 children were enrolled in this cross-sectional study. The data were collected via the Internet using a questionnaire based on the Korean-language version of the ISAAC study format. RESULTS: The prevalence of atopic dermatitis over the previous 12 months was 14.4%. The prevalence in preschool children was significantly higher than in elementary school children. Family history of atopic diseases, diagnosis of allergic conjunctivitis and diagnosis of food allergy were positively associated with atopic dermatitis in both preschool and elementary school children. In addition, raising pets was positively associated with atopic dermatitis in preschool children. In elementary school children, female gender, secondhand smoking, breastfeeding, changing the parents' house to a newly built one during the first year of life, diagnosis of asthma and diagnosis of allergic rhinitis were positively associated with atopic dermatitis. CONCLUSION: The prevalence of atopic dermatitis in preschool and elementary school children in Korea is similar to that of children in other developing countries. The risk factors for atopic dermatitis are different in preschool and elementary school children. More detailed strategies will be necessary to reduce atopic dermatitis in both age groups.

Treatment of Dowling-Degos disease with fractional Er:YAG laser.

Dowling-Degos disease (DDD) is a rare, benign, autosomal dominant disorder characterized by reticulated pigmentation on flexural areas. Recently, a report of successful Er:YAG ablative laser treatment without any adverse effects was issued. A 49-year-old Korean woman presented with numerous small, hyperpigmented macules in a reticular pattern on her face, axillae, and inguinal folds of several years duration. Histologic examination revealed acanthosis with thin elongated rete ridges, basal branching, and widening. She was diagnosed as having DDD and was treated successfully without any adverse effects using a fractional 2,940-nm Er:YAG ablative laser (LOTUSII, Laseroptek, Sungnam, Korea). Er:YAG ablative laser treatment could be an effective treatment modality for DDD, but in Asians, who have darker skins than Caucasians, or in patients with skin lesions on the face, post-inflammatory hyperpigmentation could be problematic after treatment. Fractional Er:YAG ablative laser treatment should be viewed as an alternative therapeutic option for DDD.

Analysis of Positive Patch Test Allergens in Allergic Contact Dermatitis Patients with Atopic Dermatitis.

BACKGROUND: There has been debate regarding whether patients with atopic dermatitis (AD) have an altered frequency of contact allergen sensitization. Increased exposure to topical medications and moisturizers as well as impaired skin barrier function increase the risk of contact sensitization, whereas the Th2-skewed inflammatory pathway of AD is associated with a reduced risk. OBJECTIVE: This retrospective study was performed to determine the characteristics of contact sensitization in allergic contact dermatitis (ACD) patients with a current or past history of AD. METHODS: A clinical record review was conducted for patients referred to Ewha Womans University Medical Center, for patch tests between March 2017 and March 2021. We compared the rates of contact sensitization between ACD patients with and without AD. RESULTS: In total, 515 patch test results were reviewed and divided into the AD group (n=53) and non-AD group (n=462). The AD group showed decreased any-allergen positivity (1+, 2+, or 3+) (56.6%) compared to the non-AD group (72.9%) (p=0.013). The positivity rate for budesonide was significantly higher in the AD group (p=0.011), while the prevalence of a positive result for balsam of Peru was higher in the non-AD group (p=0.036). Nickel sulfate, cobalt chloride, and potassium dichromate were the most common sensitized allergens in both groups. CONCLUSION: Our study shows a decreased prevalence of contact sensitization in AD patients compared to non-AD patients. Clinicians should be aware of the risk of corticosteroid allergies in ACD patients with history of AD.

Oncogenic signaling pathways and hallmarks of cancer in Korean patients with acral melanoma.

Acral melanoma (AM), a rare subtype of cutaneous melanoma, shows higher incidence in Asians, including Koreans, than in Caucasians. However, the genetic modification associated with AM in Koreans is not well known and has not been comprehensively investigated in terms of oncogenic signaling, and hallmarks of cancer. We performed whole-exome and RNA sequencing for Korean patients with AM and acquired the genetic alterations and gene expression profiles. KIT alterations (previously known to be recurrent alterations in AM) and CDK4/CCND1 copy number amplifications were identified in the patients. Genetic and transcriptomic alterations in patients with AM were functionally converge to the hallmarks of cancer and oncogenic pathways, including 'proliferative signal persistence', 'apoptotic resistance', and 'activation of invasion and metastasis', despite the heterogeneous somatic mutation profiles of Korean patients with AM. This study may provide a molecular understanding for therapeutic strategy for AM.

Erratum: Assessment of Disease Severity and Quality of Life in Patients with Atopic Dermatitis from South Korea.

This corrects the article on p. 419 in vol. 34, PMID: 36478424.

Prevalence and risk factors for atopic dermatitis: a cross-sectional study of 6,453 Korean preschool children.

The aims of this study were to evaluate the prevalence, severity and risk factors for atopic dermatitis in Korean pre-school children as determined by dermatological examination vs questionnaire survey. A total of 6,453 pre-school children from 59 kindergartens and 14 day-care centres were evaluated. Parents responded to an International Study of Asthma and Allergies in Childhood (ISAAC)-based questionnaire containing questions concerning 23 risk factors, as well as the prevalence, and severity of atopic dermatitis. Fourteen dermatologists then examined the participants according to the Korean diagnostic criteria for atopic dermatitis, and the Eczema Area and Severity Index (EASI) score. Atopic dermatitis prevalence determined by dermatological examination was lower than the questionnaire-based prevalence (9.2% vs 19.1%). Most patients (96.2%) had mild atopic dermatitis according to the EASI score (mean ± SD 3.91 ± 4.73; median 1.5; range 0.2-38.0). However, 17.4% had sleep disturbance, and 56.7% had not obtained complete remission of their rash over the previous 12 months. Among the 12 risk factors, "changing the patient's house to a newly built house during the first year of life" had significant odds ratio. In conclusion, the prevalence of atopic dermatitis in Korea in the ISAAC-based survey conducted by paediatricians was similar to that in several European countries, and lower than the 2006 Korean figure (28.9%). In addition, the prevalence of atopic dermatitis was lower when assessed by dermatological examination than by questionnaire.

Atypical hydroa vacciniforme-like epstein-barr virus associated T/NK-cell lymphoproliferative disorder.

Epstein-Barr virus (EBV)-associated T-cell/natural killer (NK)-cell lymphoproliferative disorders (EBV-T/NK-LPDs) accompany severe chronic active EBV infection (CAEBV) or comprise the CAEBV disease entity. The CAEBV disease entity has the common feature of lymphoproliferation of T or NK cells (primarily), and B cells (rarely), with chronic activation of EBV infection. The disease is rare and seems to be more prevalent in East Asian countries. The CAEBV disease entity encompasses heterogenous disorders, including hydroa vacciniforme (HV), hypersensitivity to mosquito bites, EBV-associated hemophagocytic syndrome, NK/T-cell lymphoma, and NK-cell leukemia. Atypical HV-like eruptions are present on sun-exposed and nonexposed areas with facial edema, fever, and hepatosplenomegaly, unlike classic HV. Recently, it has been suggested that classic HV and atypical HV-like eruptions are variants within the same disease spectrum of EBV-T/NK-LPD. We report a Korean boy with an atypical HV-like eruption and various systemic manifestations, including fever, sore throat, abdominal pain, headaches, seizures, and hematologic abnormalities for 2 years. After the initial mild eruption, which resembled a viral exanthem, ulceronecrotic skin lesions gradually developed and were associated with a high-grade fever and constitutional symptoms. He had a CAEBV infection, which showed a predominant proliferation of NK cells with high EBV DNA levels in the peripheral blood. However, in the skin lesions, there were nonneoplastic CD4 T-cell infiltrations predominantly showing a monoclonal T-cell receptor-γ gene rearrangement and positive EBV in situ hybridization.

Efficacy and safety of guselkumab compared with placebo and adalimumab in Korean patients with moderate-to-severe psoriasis: post-hoc analysis from the phase III, double-blind, placebo- and active-comparator-controlled VOYAGE 1/2 trials.

BACKGROUND: The phase 3 studies, VOYAGE 1 and 2, were conducted to assess guselkumab in the treatment of patients with moderate-to-severe psoriasis. OBJECTIVES: To investigate the efficacy and safety of guselkumab in Korean patients. METHODS: The Korean sub-population of VOYAGE 1 and 2 study patients were included in this analysis. Efficacy and safety were evaluated through Weeks 24 and 28, respectively. RESULTS: Of 126 randomized Korean patients, 30, 63, and 33 received placebo, guselkumab, and adalimumab, respectively. At Week 16, guselkumab was superior to placebo in achieving an Investigator's Global Assessment (IGA) score of 0 or 1 (cleared or minimal; 90.5 vs. 20.0%, p<.001) and a Psoriasis Area and Severity Index (PASI) 90 response (71.4 vs. 3.3%, p<.001). At week 24, a significantly higher proportion of guselkumab-treated patients achieved PASI 75 and IGA 0 (clear skin) responses compared to adalimumab-treated patients (PASI 75: 93.7 vs. 66.7%, p<.001; IGA 0: 52.4 vs. 21.2%, p=.004). Through Week 28, guselkumab and adalimumab showed comparable safety profiles. CONCLUSION: The efficacy and safety of guselkumab in Korean psoriasis patients through 28 weeks were consistent with findings for the overall VOYAGE 1 and 2 study population.

Differences in Clinical Responses to Ustekinumab Treatment among Body Regions: Results from a Real-World Prospective, Observational, and Multi-Center Study in Korea.

BACKGROUND: In psoriasis treatment, not all body regions improve simultaneously after clinical interventions. OBJECTIVE: This study was aimed at evaluating clinical responses across body regions, which may differentially influence patient treatment plans. METHODS: This prospective, observational, and multi-center study was conducted in Koreans who adhered to ustekinumab treatment based on criteria per local label and reimbursement guidelines. A total of 581 were included in this analysis. RESULTS: The mean (±standard deviation) psoriasis area severity index (PASI) score at baseline, age, disease duration, and body surface area (%) were 18.9±9.69, 44.2±13.29 years, 11.3±9.65 years, and 27.8±17.83, respectively. Across the head and neck, upper extremities, trunk, and lower extremities, the correlation between the PASI sub-scores for the upper and lower extremities was the highest (r=0.680). The mean PASI sub-score for the lower extremities was the highest at baseline. PASI90 and PASI100 scores were the highest for the head and neck region, indicating the highest response rates, while those for the lower extremities were consistently low at all visits. CONCLUSION: We found differences in regional ustekinumab responses, with the lower extremities being the most difficult to treat. These findings should be considered in psoriasis treatment.

Assessment of Disease Severity and Quality of Life in Patients with Atopic Dermatitis from South Korea.

BACKGROUND: Data illustrating the impact of atopic dermatitis (AD) on lives of adults with AD in South Korea are limited. OBJECTIVE: To assess the AD disease severity and its impact on quality of life (QoL) in patients with AD from South Korea. METHODS: Patients with AD utilizing the specialist dermatology services of major hospitals in South Korea were assessed for disease severity using Eczema Area and Severity Index (EASI) score, for QoL using Dermatology Life Quality Index (DLQI) (for QoL), and for comorbidities and treatment experience via retrospective review of 12-month medical records. Clinical and sociodemographic characteristics were also measured. RESULTS: Of the 1,163 patients, 695 (59.8%) were men (mean age [years]±standard deviation: 31.6±12.1). Overall, 52.9% (n=615) patients had moderate-to-severe disease (EASI>7). The QoL of 72.3% (n=840) patients was affected moderately-to-severely (DLQI score: 6~30). Systemic immunosuppressants were used ≥1 over past 12 months in 51.9% (n=603) patients, and the most commonly used were cyclosporines (45.7%, n=531) and systemic corticosteroids (40.5%, n=471). Approximately, 10.8% (n=126) patients consulted or received treatment for AD-related eye problem. Of these, 40% (n=50) patients reported poor, very poor, or completely blind status; approximately, 16.7% patients (n=192) reported having depression or anxiety; and 35.5% (n=410) reported suicidal ideation or suicidal attempt. CONCLUSION: A large proportion of patients had moderate-to-severe AD, a compromised QoL, and ocular or mental health comorbidities, indicating a high disease burden despite systemic treatment. These findings highlight the importance of a holistic approach for the evaluation and treatment of patients with AD.

A novel function of Siglec-9 A391C polymorphism on T cell receptor signaling.

BACKGROUND: Sialic-acid-binding immunoglobulin-like lectins (Siglecs) are the best-characterized immunoglobulin-type lectins. There is a growing amount of data linking Siglec and autoimmune diseases. The recently identified Siglec-9 inhibits T cell receptor (TCR)-mediated signaling which has been demonstrated by site-directed mutagenesis. In human Siglec-9, at least 8 nonsynonymous SNPs have been detected without functional studies. This study examined the SNP(s) related to TCR-mediated signaling. METHODS: Since the functions of Siglecs are modulated by their interaction with sialic-acid-containing carbohydrate groups, a molecular modeling analysis of carbohydrate binding interactions and an RBC binding analysis were performed using the 8 SNPs. The TCR-mediated signaling was analyzed with the downstream signaling molecules ZAP-70 and IL-2. RESULTS: This study revealed that an A391C polymorphism is the only mutant related to the binding. Jurkat T cells transfected with the A391C mutant reduced the inhibition of ZAP-70 phosphorylation and IL-2 production compared to cells transfected with the wild type. CONCLUSIONS: Siglec-9 A391C was the only polymorphism related to TCR-mediated signaling in human Siglec-9, resulting in less inhibition compared to the wild type.