A method for measuring serum levels of melanin-associated indole metabolites using LC-MS/MS and its application to malignant melanoma.

BACKGROUND AND AIMS: With the development of novel therapies for advanced malignant melanoma (MM), biomarkers that can accurately reflect the progression of MM are needed. Serum levels of melanin-related indole metabolites such as 5-hydroxy-6-methoxyindole-2-carboxylic acid (5H6MI2C) and 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI2C) are potential biomarkers for MM. Here, we describe the development of a mass spectrometry (MS)-based assay to determine serum levels of 5H6MI2C and 6H5MI2C. MATERIALS AND METHODS: We developed a stable isotope dilution-selective reaction monitoring-MS protocol using liquid chromatography tandem mass spectrometry (LC-MS/MS) to measure human serum 5H6MI2C and 6H5MI2C levels. Analytical evaluations of the method were performed and the method was applied to serum samples from MM patients (n = 81). RESULTS: The method established in this study showed high reproducibility and linearity. This novel method also found that serum 6H5MI2C levels were significantly elevated in patients with metastatic MM compared to those with non-metastatic MM. Unfortunately, 5H6MI2C did not show a comparable significant difference. CONCLUSION: We successfully established measurement methods for serum 5H6MI2C and 6H5MI2C levels using LC-MS/MS. Serum 6H5MI2C levels offer a potential marker for MM.

Elevated expression of interleukin-6 (IL-6) and serum amyloid A (SAA) in the skin and the serum of recessive dystrophic epidermolysis bullosa: Skin as a possible source of IL-6 through Toll-like receptor ligands and SAA.

The effect of persistent skin inflammation on extracutaneous organs and blood is not well studied. Patients with recessive dystrophic epidermolysis bullosa (RDEB), a severe form of the inherited blistering skin disorder, have widespread and persistent skin ulcers, and they develop various complications including anaemia, hyperglobulinaemia, hypoalbuminaemia and secondary amyloidosis. These complications are associated with the bioactivities of IL-6, and the development of secondary amyloidosis requires the persistent elevation of serum amyloid A (SAA) level. We found that patients with RDEB had significantly higher serum levels of IL-6 and SAA compared to healthy volunteers and patients with psoriasis or atopic dermatitis. Both IL-6 and SAA were highly expressed in epidermal keratinocytes and dermal fibroblasts of the skin ulcer lesions. Keratinocytes and fibroblasts surrounding the ulcer lesions are continuously exposed to Toll-like receptor (TLR) ligands, pathogen-associated and damage-associated molecular pattern molecules. In vitro, TLR ligands induced IL-6 expression via NF-κB in normal human epidermal keratinocytes (NHEKs) and dermal fibroblasts (NHDFs). SAA further induced the expression of IL-6 via TLR1/2 and NF-κB in NHEKs and NHDFs. The limitation of this study is that NHEKs and NHDFs were not derived from RDEB patients. These observations suggest that TLR-mediated persistent skin inflammation might increase the risk of IL-6-related systemic complications, including RDEB.

Topical application of activator protein-1 inhibitor T-5224 suppresses inflammation and improves skin barrier function in a murine atopic dermatitis-like dermatitis.

BACKGROUND: Selective activator protein (AP)-1 inhibitors are potentially promising therapeutic agents for atopic dermatitis (AD) because AP-1 is an important regulator of skin inflammation. However, few studies have investigated the effect of topical application of AP-1 inhibitors in treating inflammatory skin disorders. METHODS: Immunohistochemistry was conducted to detect phosphorylated AP-1/c-Jun expression of skin lesions in AD patients. In the in vivo study, 1 % T-5224 ointment was topically applied for 8 days to the ears of 2,4 dinitrofluorobenzene challenged AD-like dermatitis model mice. Baricitinib, a conventional therapeutic agent Janus kinase (JAK) inhibitor, was also topically applied. In the in vitro study, human epidermal keratinocytes were treated with T-5224 and stimulated with AD-related cytokines. RESULTS: AP-1/c-Jun was phosphorylated at skin lesions in AD patients. In vivo, topical T-5224 application inhibited ear swelling (P < 0.001), restored filaggrin (Flg) expression (P < 0.01), and generally suppressed immune-related pathways. T-5224 significantly suppressed Il17a and l17f expression, whereas baricitinib did not. Baricitinib suppressed Il4, Il19, Il33 and Ifnb expression, whereas T-5224 did not. Il1a, Il1b, Il23a, Ifna, S100a8, and S100a9 expression was cooperatively downregulated following the combined use of T-5224 and baricitinib. In vitro, T-5224 restored the expression of FLG and loricrin (LOR) (P < 0.05) and suppressed IL33 expression (P < 0.05) without affecting cell viability and cytotoxicity. CONCLUSIONS: Topical T-5224 ameliorates clinical manifestations of AD-like dermatitis in mice. The effect of this inhibitor is amplified via combined use with JAK inhibitors.

"Input/output cytokines" in epidermal keratinocytes and the involvement in inflammatory skin diseases.

Considering the role of epidermal keratinocytes, they occupy more than 90% of the epidermis, form a physical barrier, and also function as innate immune barrier. For example, epidermal keratinocytes are capable of recognizing various cytokines and pathogen-associated molecular pattern, and producing a wide variety of inflammatory cytokines, chemokines, and antimicrobial peptides. Previous basic studies have shown that the immune response of epidermal keratinocytes has a significant impact on inflammatory skin diseases. The purpose of this review is to provide foundation of knowledge on the cytokines which are recognized or produced by epidermal keratinocytes. Since a number of biologics for skin diseases have appeared, it is necessary to fully understand the relationship between epidermal keratinocytes and the cytokines. In this review, the cytokines recognized by epidermal keratinocytes are specifically introduced as "input cytokines", and the produced cytokines as "output cytokines". Furthermore, we also refer to the existence of biologics against those input and output cytokines, and the target skin diseases. These use results demonstrate how important targeted cytokines are in real skin diseases, and enhance our understanding of the cytokines.

Co-occurrence of non-alcoholic steatohepatitis exacerbates psoriasis associated with decreased adiponectin expression in a murine model.

Introduction: Clinical studies have suggested a bidirectional association between non-alcoholic steatohepatitis (NASH) and psoriasis, affecting each other's development and severity. Here, we explored bidirectional causal linkages between NASH and psoriasis using a murine model. Methods: NASH was induced in mice by streptozotocin injection at 2 days of age and by high-fat diet feeding (STAM™ model). Psoriasis was induced by topical application of imiquimod (IMQ) on the ear. The severities of liver damage and psoriatic skin changes were determined using histological analysis. Gene expression in the skin tissues was evaluated using quantitative PCR analysis. Serum cytokine levels were determined using enzyme-linked immunosorbent assay. To examine the innate immune responses of normal human epidermal keratinocytes (NHEKs), the cells were treated with interleukin (IL)-17A, tumor necrosis factor (TNF)-α, and AdipoRon, an adiponectin receptor agonist. Results and Discussion: There were no differences in the degree of liver tissue damage (fat deposition, inflammation, and fibrosis) between NASH mice with and those without psoriasis. Conversely, the co-occurrence of NASH significantly augmented psoriatic skin changes, represented by epidermal hyperplasia, in psoriatic mice. Pro-inflammatory cytokines were expressed in the inflamed skin of psoriatic mice, and the expression of genes, especially Il23a, Il1b, Il36g, and Mip2, was significantly upregulated by the co-occurrence of NASH. The expression of keratinocyte activation marker genes Defb4b and Krt16 was also upregulated by the co-occurrence of NASH. The serum TNF-α and IL-17 levels were increased by the co-occurrence of NASH and psoriasis. The serum adiponectin levels decreased in NASH mice compared with that in non-NASH mice. In NHEK culture, TNF-α and IL-17A synergistically upregulated CXCL1, CXCL8, and IL1B expression. The upregulated pro-inflammatory gene expression was suppressed by AdipoRon treatment, reflecting the anti-inflammatory capacity of adiponectin. Conclusion: The co-occurrence of NASH exacerbated psoriatic skin changes associated with increased serum inflammatory cytokine levels and decreased serum adiponectin levels. Combined with in vitro findings, increased inflammatory cytokine levels and decreased adiponectin levels likely promote innate immune responses in epidermal keratinocytes in psoriatic skin lesions. Overall, therapeutic intervention for co-occurring NASH is essential to achieve a favorable prognosis of psoriasis in clinical practice.

Coexpression of natural killer cell antigens by T-cell large granular lymphocytes in hydroa vacciniforme lymphoproliferative disorder and the involvement of Vδ1 + epithelial-type γδT cells.

Hydroa vacciniforme lymphoproliferative disorder (HV-LPD) is a cutaneous variant of chronic active Epstein-Barr virus disease. We examined the coexpression of T- and natural killer (NK)-cell antigens in five patients with classic HV (cHV) and five with systemic HV (sHV). T-cell receptor (TCR) repertoire analysis was performed with high­throughput sequencing. All five cHV patients had increased γδT cells (> 5%), whereas five sHV patients showed γδT- and αßT-cell dominance in two patients each, and a mixture of abnormal γδT and αßT cells in one. Circulating CD3 + T cells expressed CD16/CD56 at 7.8-42.3% and 1.1-9.7% in sHV and cHV, respectively. The percentage of CD16/CD56 + T cells was higher in the large granular lymphocyte or atypical T-cell fractions in sHV, but no TCR Vα24 invariant chain characteristic of NKT cells was detected. Considerable numbers of CD3 + cells expressing CD56 were observed in sHV skin infiltrates. Of the circulating γδT cells tested, TCR Vδ1 + cells characteristic of the epithelial type of γδT cells were dominant in two sHV cases. Thus, atypical αßT and γδT cells in HV-LPD can express NK-cell antigens, such as CD16 and CD56, and Vδ1 + epithelial-type γδT cells are a major cell type in some HV-LPD cases.

Survival rates of systemic interventions for psoriasis in the Western Japan Psoriasis Registry: A multicenter retrospective study.

Psoriasis affects approximately 0.3% of the Japanese population. Recently, various effective systemic drugs have become available, and the continuation of a given treatment has become critical because of the chronic nature of psoriasis. Factors affecting drug survival (the time until treatment discontinuation) in psoriasis treatment include efficacy, safety, ease of use, and patient preference. In the present study, the authors retrospectively surveyed a multifacility patient registry to determine the real-world evidence of the survival rate of systemic interventions for psoriasis treatment. Patients with psoriasis who visited 20 facilities in the Western Japan area between January 2019 and May 2020 and gave written consent were registered as study participants, and their medical history of systemic interventions for psoriasis (starting from 2010) was retrospectively collected and analyzed. The drugs investigated were adalimumab, infliximab, ustekinumab, secukinumab, ixekizumab, brodalumab, guselkumab, risankizumab, cyclosporine, and apremilast. When drugs were discontinued, the reasons were also recorded. A total of 1003 patients with psoriasis including 268 with psoriatic arthritis (PsA) were enrolled. In biologics, more recently released drugs such as interleukin 17 inhibitors showed a numerically higher survival rate in the overall (post-2010) analysis. However, in the subset of patients who began treatment after 2017, the difference in the survival rate among the drugs was smaller. The reasons for discontinuing drugs varied, but a loss of efficacy against dermatological or joint symptoms were relatively frequently seen with some biologics and cyclosporine. The stratification of drug survival rates based on patient characteristics such as bio-naive or experienced, normal weight or obese, and with or without PsA, revealed that bio-experienced, obese, and PsA groups had poorer survival rates for most drugs. No notable safety issues were identified in this study. Overall, the present study revealed that the biologics show differences in their tendency to develop a loss of efficacy, and the factors that negatively impact the survival rate of biologics include the previous use of biologics, obesity, and PsA.

Clinical characteristics of patients with psoriasis with family history: A multicenter observational study.

Previous studies on family history of psoriasis showed that patients with a family history have an earlier onset of the disease, but such studies in Japan are still limited. To elucidate the characteristics of patients with familial psoriasis, we studied the family history of patients with psoriasis using the West Japan Psoriasis Registry, a multi-institutional registry operated by 26 facilities in the western part of Japan, including university hospitals, community hospitals, and clinics. This study enrolled 1847 patients registered between September 2019 and December 2021, with 199 (10.8%) having a family history of psoriasis. Patients with a family history of psoriasis had significantly earlier onset of the disease than those without a family history. Furthermore, patients with a family history of psoriasis had significantly longer disease duration. Psoriatic arthritis (PsA) was significantly more common in patients with a family history (69/199, 34.7%) than in those without a family history (439/1648, 26.6%) (adjusted P = 0.023). A subanalysis of patients with PsA revealed a significant difference in the patient global assessment (PaGA) score in Fisher's exact test and adjusted test. The numbers of patients with PaGA 0/1 were 29 (43.3%) and 172 (39.9%) in patients with PsA with and without family history of psoriasis, respectively, whereas the numbers of patients with PaGA 3/4 were 13 (19.4%) and 145 (33.6%) in patients with PsA with and without family history of psoriasis, respectively. Other disease severity variables did not show a difference between the two groups. Our findings suggest that genetics play a larger role in the development of PsA than in the development of psoriasis vulgaris. Most cases of PsA occur in patients who already have psoriasis, therefore dermatologists should pay attention to joint symptoms, especially in patients with psoriasis who have a family history of psoriasis.

Ceramide Analysis in Combination With Genetic Testing May Provide a Precise Diagnosis for Self-Healing Collodion Babies.

Self-healing collodion baby (SHCB), also called "self-improving collodion baby", is a rare mild variant of autosomal recessive congenital ichthyosis and is defined as a collodion baby who shows the nearly complete resolution of scaling within the first 3 months to 1 year of life. However, during the neonatal period, it is not easy to distinguish SHCB from other inflammatory forms of autosomal recessive congenital ichthyosis, such as congenital ichthyosiform erythroderma. Here, we report a case study of two Japanese SHCB patients with compound heterozygous mutations, c.235G>T (p.(Glu79∗))/ c.1189C>T (p.(Arg397Cys)) and c.1295A>G (p.(Tyr432Cys))/ c.1138delG (p.(Asp380Thrfs∗3)), in CYP4F22, which encodes cytochrome P450, family 4, subfamily F, polypeptide 22 (CYP4F22). Immunohistochemically, inflammation with the strong expression of IL-17C, IL-36γ, and TNF-α was seen in the skin at birth. CYP4F22 is an ultra-long-chain FA ω-hydroxylase responsible for ω-O-acylceramide (acylceramide) production. Among the epidermal ceramides, acylceramide is a key lipid in maintaining the epidermal permeability barrier function. We found that the levels of ceramides with ω-hydroxy FAs including acylceramides and the levels of protein-bound ceramides were much lower in stratum corneum samples obtained by tape stripping from SHCB patients than in those from their unaffected parents and individuals without SHCB. Additionally, our cell-based enzyme assay revealed that two mutants, p.(Glu79∗) and p.(Arg397Cys), had no enzyme activity. Our findings suggest that genetic testing coupled with noninvasive ceramide analyses using tape-stripped stratum corneum samples might be useful for the early and precise diagnosis of congenital ichthyoses, including SHCB.

Probability scoring system of intravascular large B-cell lymphoma for the application of random skin biopsy: A retrospective cohort study.

Background: Intravascular large B-cell lymphoma (IVLBCL) is rare and fatal when diagnosed late in the disease course. Random skin biopsy (RSB) is useful for early diagnosis, but criteria for its application are not well established. Objective: To develop an IVLBCL-probability scoring system for stratifying patients and investigate its feasibility and capability for RSB application. Methods: A retrospective cohort of 77 consecutive patients with suspected IVLBCL who underwent RSB was included in this study. All patients were classified into 3 IVLBCL-probability groups according to the IVLBCL-probability scoring system comprising the following 4 components: general symptoms, organ-specific symptoms, serum soluble-interleukin-2 receptor levels, and serum lactate-dehydrogenase levels. Results: The high (score 7-10), intermediate (score 4-6) and low (score 1-3) IVLBCL-probability groups contained 32, 30, and 15 patients, respectively. All 5 patients with IVLBCL were stratified into the high IVLBCL probability group. Accuracies in the diagnosis of IVLBCL were 100%, 100%, and 93.8% for the low, intermediate, and high IVLBCL-probability groups. The positive detection rate in the high IVLBCL-probability group increased to 9.4% from 3.9% across all groups. Conclusions: The newly-developed IVLBCL-probability scoring system has good capability for stratification of patients and could allow limiting application of RSB for diagnosis only to high-probability groups.