Variants of C-C Motif Chemokine 22 (CCL22) Are Associated with Susceptibility to Atopic Dermatitis: Case-Control Studies

Atopic dermatitis (AD) is a common inflammatory skin disease caused by multiple genetic and environmental factors. AD is characterized by the local infiltration of T helper type 2 (Th2) cells. Recent clinical studies have shown important roles of the Th2 chemokines, CCL22 and CCL17 in the pathogenesis of AD. To investigate whether polymorphisms of the CCL22 gene affect the susceptibility to AD, we conducted association studies and functional studies of the related variants. We first resequenced the CCL22 gene and found a total of 39 SNPs. We selected seven tag SNPs in the CCL22 gene, and conducted association studies using two independent Japanese populations (1st population, 916 cases and 1,032 controls; 2nd population 1,034 cases and 1,004 controls). After the association results were combined by inverse variance method, we observed a significant association at rs4359426 (meta-analysis, combined P = 9.6×10−6; OR, 0.74; 95% CI, 0.65–0.85). Functional analysis revealed that the risk allele of rs4359426 contributed to higher expression levels of CCL22 mRNA. We further examined the allelic differences in the binding of nuclear proteins by electrophoretic mobility shift assay. The signal intensity of the DNA-protein complex derived from the G allele of rs223821, which was in absolute LD with rs4359426, was higher than that from the A allele. Although further functional analyses are needed, it is likely that related variants play a role in susceptibility to AD in a gain-of-function manner. Our findings provide a new insight into the etiology and pathogenesis of AD

Antioxidant Opuntia ficus-indica extract activates AHR-NRF2 signaling and upregulates filaggrin and loricrin expression in human keratinocytes

Opuntia ficus-indica (OFI) is a cactus species widely used as an anti-inflammatory, antilipidemic, and hypoglycemic agent. It has been shown that OFI extract (OFIE) inhibits oxidative stress in animal models of diabetes and hepatic disease; however, its antioxidant mechanism remains largely unknown. In this study, we demonstrated that OFIE exhibited potent antioxidant activity through the activation of nuclear factor erythroid 2-related factor 2 (NRF2) and the downstream antioxidant enzyme NAD(P)H:quinone oxidoreductase 1 (NQO1), which inhibited the generation of reactive oxygen species in keratinocytes challenged with tumor necrosis factor α or benzo[α]pyrene. The antioxidant capacity of OFIE was canceled in NRF2 knockdown keratinocytes. OFIE exerted this NRF2-NQO1 upregulation through activation of the aryl hydrocarbon receptor (AHR). Moreover, the ligation of AHR by OFIE upregulated the expression of epidermal barrier proteins: filaggrin and loricrin. OFIE also prevented TH2 cytokine-mediated downregulation of filaggrin and loricrin expression in an AHR-dependent manner because it was canceled in AHR knockdown keratinocytes. Antioxidant OFIE is a potent activator of AHR-NRF2-NQO1 signaling and may be beneficial in treating barrier-disrupted skin disorders

Identification of novel immune and barrier genes in atopic dermatitis by means of laser capture microdissection

BACKGROUND: The molecular signature of atopic dermatitis/AD lesions is associated with Th2 and Th22 activation, and epidermal alterations. However, the epidermal and dermal AD transcriptomes and their respective contributions to abnormalities in respective immune and barrier phenotypes are unknown. OBJECTIVE: To establish the genomic profile of the epidermal and dermal compartments of lesional/LS and non-lesional/NL AD, as compared with normal skin. METHODS: Laser capture micro-dissection/LCM was performed to separate epidermis and dermis of LS and NL skin from AD patients and normal skin from healthy volunteers followed by gene expression (microarrays and RT-PCR) and immunostaining studies. RESULTS: Our study identified novel immune and barrier genes, including the IL-34 cytokine and claudins 4 and 8, and showed increased detection of key AD genes usually undetectable on arrays (i.e. IL-22, TSLP, CCL22, and CCL26). Overall, the combined epidermal and dermal transcriptomes enlarged the AD transcriptome adding 674 up-regulated and 405 down-regulated differentially expressed genes between LS and NL skin to the AD transcriptome. We were also able to localize individual transcripts as primarily epidermal (DEFB4A) or dermal (IL-22, CTLA4, and CCR7), and link their expressions to possible cellular sources. CONCLUSIONS: This is the first report that establishes robust epidermal and dermal genomic signatures of LS, NL AD and normal/N skin, as compared with whole tissues. These data establish the utility of LCM to separate different compartments and cellular subsets in AD, allowing localization of key barrier or immune molecules, and enable detection of gene products usually not detected on arrays

Comparison between Patch Test Results using Patch Test Panel® (S) and Japanese Standard Allergen Series (2008)

Patch testing (PT) is useful for identifying the cause of treatment-resistant dermatitis. The Japanese standard allergen series (2008) (JSA2008) is useful for identifying allergens among substances producing false negative PT results and for revealing unexpected causes of allergic reactions. When performing PT, JSA2008 should be used as much as possible. However, since 2015, Patch Test Panel^® (S) has also been available in Japan. This is a ready-to-use PT consisting of 22 standard allergens. Given that 21 of the 22 allergens are shared with JSA2008, Patch Test Panel^®(S) is now becoming popular because of its ease of use and timesaving advantage. However, a comparison between PT results using Patch Test Panel^®(S) and JSA2008 has not been reported in patients living in northern Kyushu. This study compared the PT results using Patch Test Panel^®(S) with those using JSA2008 in patients who visited Kyushu University Hospital and Fukuoka Dental College Hospital. Significantly higher rates of positive PT results were found for gold sodium thiosulfate (p＜0.001) and nickel sulfate (p＜0.001) using Patch Test Panel^®(S).パッチテストは，治療抵抗性皮膚炎の原因を特定するのに有用である．2015 年まで広く使用されていたジャパニーズスタンダードアレルゲンシリーズ（2008）（JSA2008）は，私たちの身近にあってアレルゲンとなりうる可能性の高いものを集めた標準アレルゲンで，予期しない原因やアレルゲンを明らかにするために有用であり，PT を実施する場合，できるだけJSA2008の使用が推奨されてきた．加えて2015年以降，Patch Test Panel^®（S）が日本で発売された．これは，22 種類の標準アレルゲンで構成されたすぐに使用できるready-to-use のPT で，22 種類のアレルゲンのうち21 種類がJSA2008 と同じであるため使いやすく，試薬調整も不要で時間節約となることなどから普及しつつある．しかし，Patch Test Panel^® (S）とJSA2008 を用いた北部九州に住む患者のPT 結果の比較は報告されていない．本研究では，九州大学病院，福岡歯科大学病院においてJSA2008 とPatch Test Panel^®（S）を用いたPT 結果を比較した．その結果，Patch Test Panel^®（S）においては，JSA2008と比較して，金チオ硫酸ナトリウム（p＜0.001）および硫酸ニッケル（p ＜ 0.001）の陽性率が有意に高かった．これらの結果を今後，全国的な症例の蓄積をもとに，至適濃度の検討などに活かしていく必要があると考えた．パッチテストは，治療抵抗性皮膚炎の原因を特定するのに有用である．2015 年まで広く使用されていたジャパニーズスタンダードアレルゲンシリーズ（2008）（JSA2008）は，私たちの身近にあってアレルゲンとなりうる可能性の高いものを集めた標準アレルゲンで，予期しない原因やアレルゲンを明らかにするために有用であり，PT を実施する場合，できるだけJSA2008の使用が推奨されてきた．加えて2015年以降，Patch Test Panel^®（S）が日本で発売された．これは，22 種類の標準アレルゲンで構成されたすぐに使用できるready-to-useのPTで，22 種類のアレルゲンのうち21 種類がJSA2008 と同じであるため使いやすく，試薬調整も不要で時間節約となることなどから普及しつつある．しかし，Patch Test Panel^®(S）とJSA2008 を用いた北部九州に住む患者のPT 結果の比較は報告されていない．本研究では，九州大学病院，福岡歯科大学病院においてJSA2008 とPatch TestPanel^®（S）を用いたPT 結果を比較した．その結果，Patch Test Panel^®（S）においては，JSA2008と比較して，金チオ硫酸ナトリウム（p＜0.001）および硫酸ニッケル（p＜0.001）の陽性率が有意に高かった．これらの結果を今後，全国的な症例の蓄積をもとに，至適濃度の検討などに活かしていく必要があると考えた．Introduction / Materials and Methods / Results / Discussio

Dupilumab progressively improves systemic and cutaneous abnormalities in patients with atopic dermatitis

© 2018 The Authors Background: Dupilumab is an IL-4 receptor α mAb inhibiting signaling of IL-4 and IL-13, key drivers of type 2–driven inflammation, as demonstrated by its efficacy in patients with atopic/allergic diseases. Objective: This placebo-controlled, double-blind trial (NCT01979016) evaluated the efficacy, safety, and effects of dupilumab on molecular/cellular lesional and nonlesional skin phenotypes and systemic type 2 biomarkers of patients with moderate-to-severe atopic dermatitis (AD). Methods: Skin biopsy specimens and blood were evaluated from 54 patients randomized 1:1 to weekly subcutaneous doses of 200 mg of dupilumab or placebo for 16 weeks. Results: Dupilumab (vs placebo) significantly improved clinical signs and symptoms of AD, was well tolerated, and progressively shifted the lesional transcriptome toward a nonlesional phenotype (weeks 4–16). Mean improvements in a meta-analysis–derived AD transcriptome (genes differentially expressed between lesional and nonlesional skin) were 68.8% and 110.8% with dupilumab and −10.5% and 55.0% with placebo (weeks 4 and 16, respectively; P \u3c.001). Dupilumab significantly reduced expression of genes involved in type 2 inflammation (IL13, IL31, CCL17, CCL18, and CCL26), epidermal hyperplasia (keratin 16 [K16] and MKi67), T cells, dendritic cells (ICOS, CD11c, and CTLA4), and TH17/TH22 activity (IL17A, IL-22, and S100As) and concurrently increased expression of epidermal differentiation, barrier, and lipid metabolism genes (filaggrin [FLG], loricrin [LOR], claudins, and ELOVL3). Dupilumab reduced lesional epidermal thickness versus placebo (week 4, P =.001; week 16, P =.0002). Improvements in clinical and histologic measures correlated significantly with modulation of gene expression. Dupilumab also significantly suppressed type 2 serum biomarkers, including CCL17, CCL18, periostin, and total and allergen-specific IgEs. Conclusion: Dupilumab-mediated inhibition of IL-4/IL-13 signaling through IL-4 receptor α blockade significantly and progressively improved disease activity, suppressed cellular/molecular cutaneous markers of inflammation and systemic measures of type 2 inflammation, and reversed AD-associated epidermal abnormalities

Pairwise linkage disequilibrium (r²) among eight SNPs in strong LD with rs4359426 in 94 control subjects.

<p>Two tag SNPs, rs170360 and rs223823, were selected for further association study. Underlined SNPs were examined.</p

Genotype counts and case-control association test results of seven tag SNPs.

<p><i>P</i> values of the two populations were calculated by logistic regression analysis under an additive model. The combined <i>P</i> values were calculated using the inverse variance method. OR, odds ratio; CI, confidence interval; -, not significant.</p

Allelic imbalance of gene expression of <i>CCL22</i> in EBV-transformed cells with heterozygous genotypes.

<p>(<b>A</b>) Genomic structures, locations and LD of the two SNPs. (<b>B</b>) Haplotypes for the two SNPs in the 1^st population. (<b>C</b>) The allelic ratio of PCR products from individuals. Heterozygous (left) and homozygous (right) at rs4359426. *Two-tailed <i>P</i> = 0.0000006 by the Mann-Whitney U test.</p

Electrophoretic mobility shift assays of rs223821.

<p>EMSA was performed using nuclear extracts from THP-1 cells stimulated with LPS (1.0 µg/ml) for 1 hour. DIG-labeled oligonucleotides corresponding to the G allele (lanes 1–5) and A allele (lanes 6–10) were used as probes. Three independent experiments were performed with similar results.</p