Yayoi Tada

Interleukin-12 p40 gene (IL12B) 3'-untranslated region polymorphism is associated with susceptibility to atopic dermatitis and psoriasis vulgaris.

Interleukin-12 (IL-12) is believed to play an important role in inducing Th1-type cytokine profiles. Atopic dermatitis (AD) and psoriasis vulgaris (PsV) are considered to be Th2 and Th1 type disease, respectively. The IL-12 p40 subunit gene (IL12B) is located at chromosome 5q31-33 and linkage findings of AD on 5q31 were reported. Recently single nucleotide polymorphism (SNP) (1188A/C) of IL12B has been reported. In function, it has been reported that this SNP is associated with IL12B mRNA expression levels. To learn whether this SNP is associated with susceptibility to AD or PsV, we investigated the genotype and allele frequencies of the SNP in AD patients, in PsV patients and in controls, examining 164 AD patients, 143 PsV patients and 100 healthy individuals in Japanese population. Genotyping was performed using the polymerase chain reaction-restriction fragment length polymorphism method. The A allele was decreased in AD patients (40.9%, p = 0.031) and increased in PsV patients (60.1%, p = 0.035) compared with controls (50.5%). This suggests that IL12B SNP is associated with susceptibility to AD and PsV, presumably by affecting the Th1/Th2 balance.

Serum macrophage-derived chemokine (MDC) levels are closely related with the disease activity of atopic dermatitis

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease characterized by the predominant infiltration of T cells, eosinophils and macrophages in lesional skin. Recently, macrophage‐derived chemokine (MDC)/CCL22, a CC chemokine, was identified as a selective chemoattractant for CC chemokine receptor 4 (CCR4)‐expressing cells, in addition to thymus and activation‐regulated chemokine (TARC). We have previously reported that serum TARC levels correlate with the severity of AD. In this report, we investigated the participation of MDC in AD. First, we measured serum MDC levels in 45 patients with AD, 25 patients with psoriasis vulgaris and 25 healthy controls. Serum MDC levels in AD patients were significantly higher than those in healthy controls and psoriasis patients. Furthermore, the increases in serum MDC levels in AD patients were greater in the severely affected group than in the moderate or mild groups. We compared serum MDC levels in 11 AD patients, before and after treatment, and observed a significant decrease after treatment. Moreover, the serum MDC levels significantly correlated with the Scoring AD (SCORAD) index, serum soluble (s) E‐selectin levels, serum soluble interleukin‐2 receptor (sIL‐2R) levels, serum TARC levels and eosinophil numbers in peripheral blood. Our study strongly suggests that serum MDC levels have a notable correlation with disease activity and that MDC, as well as the CC chemokine TARC, may be involved in the pathogenesis of AD.

IL‐18 enhances IFN‐γ‐induced production of CXCL9, CXCL10, and CXCL11 in human keratinocytes

IL‐18 is involved in the pathogenesis of atopic dermatitis, psoriasis, and allergic contact dermatitis. CXCL9, CXCL10, and CXCL11 recruit type 1 T cells, and the production of these chemokines by keratinocytes is enhanced in these dermatoses. We examined the in vitro effects of IL‐18 on IFN‐γ‐induced CXCL9, CXCL10, and CXCL11 production in human keratinocytes. IL‐18 enhanced the IFN‐γ‐induced secretion and mRNA expression of CXCL9, CXCL10, and CXCL11 in parallel to the activation of NF‐κB, STAT1, and IFN‐regulatory factor (IRF)‐1. Antisense oligonucleotides against NF‐κB p50, p65, or STAT1 suppressed CXCL9, CXCL10, and CXCL11 production, and antisense IRF‐1 suppressed CXCL11 production. Inhibitors of PI3 K, p38 MAPK, and MEK suppressed IL‐18 plus IFN‐γ‐induced CXCL9, CXCL10, and CXCL11 production and NF‐κB, STAT1, and IRF‐1 activities. IL‐18 induced phosphorylation of ERK and Akt, while IFN‐γ induced phosphorylation of p38 MAPK. These results suggest that IL‐18 may potentiate IFN‐γ‐induced CXCL9, CXCL10, and CXCL11 production in keratinocytes by activating NF‐κB, STAT1, or IRF‐1 through PI3 K/Akt and MEK/ERK pathways. These effects of IL‐18 may promote the infiltration of type 1 T cells into lesions with inflammatory dermatoses and amplify the skin inflammation. IL‐18 may act as a pro‐inflammatory cytokine in these dermatoses and thus is a candidate therapeutic target.

Granulocyte/Macrophage Colony-Stimulating Factor Inhibits IL-12 production of Mouse Langerhans Cells

We investigated the capacity of mouse Langerhans cells (LC) to produce IL-12, a central cytokine in a Th1 type of immune responses. We prepared purified LC (>95%) from BALB/c mouse skin by the panning method using anti-I-Ad mAb. An ELISA showed that purified LC spontaneously produced IL-12 p40, and that its production was up-regulated following simultaneous stimulation with anti-CD40 mAb and IFN-γ. Surprisingly, GM-CSF strikingly inhibited IL-12 p40 production by anti-CD40/IFN-γ-stimulated LC (% inhibition = 97.0 ± 0.9% at 1 ng/ml GM-CSF). Supernatants of 48-h cultured keratinocytes (KC) also caused the inhibition of LC IL-12 p40 secretion, and this effect was neutralized by anti-GM-CSF mAb. IL-1α (1 ng/ml)-stimulated KC produced much more GM-CSF than unstimulated KC (60.9 ± 0.2 pg/ml vs 20.9 ± 1.7 pg/ml), and IL-1α-stimulated KC supernatants strongly inhibited IL-12 p40 production by anti-CD40/IFN-γ-stimulated LC (% inhibition = 89.4 ± 1.4%). A bioassay using an IL-12-dependent T cell line demonstrated the correlation of the level of IL-12 p40 with the bioactivity of IL-12. These results provide important implications for the pathogenesis of atopic dermatitis, which involves the participation of LC and KC with the capacity to produce IL-12 and GM-CSF, respectively.

Serum Levels of Galectin-3: Possible Association with Fibrosis, Aberrant Angiogenesis, and Immune Activation in Patients with Systemic Sclerosis

Objective. Galectin-3 is a multifunctional protein implicated in a variety of biological processes including fibrosis, angiogenesis, and immune activation, all of which are associated with the development of systemic sclerosis (SSc). We investigated the clinical significance of serum galectin-3 levels in SSc. Methods. Serum galectin-3 levels were determined by a specific ELISA in 58 patients with SSc and 19 healthy controls. Results. Serum galectin-3 levels were significantly lower in patients with diffuse cutaneous SSc (dcSSc) than in controls (3.29 ± 3.27 ng/ml vs 4.91 ± 2.67 ng/ml, respectively; p < 0.05), while being comparable between limited cutaneous SSc (3.70 ± 2.39 ng/ml) and healthy controls. In dcSSc, serum galectin-3 levels significantly correlated with total skin score (r = 0.45, p < 0.05). Serum galectin-3 levels were significantly decreased in early dcSSc (disease duration < 1 year; 1.64 ± 1.74 ng/ml; p < 0.05), but not in mid-stage dcSSc (1 to 6 years; 3.22 ± 3.16 ng/ml) or late-stage dcSSc (> 6 years; 4.86 ± 4.10 ng/ml), compared with controls. Serum galectin-3 levels were higher in SSc patients with both digital ulcers (DU) and elevated right ventricular systolic pressure (RVSP) than in those without each symptom (DU: 5.44 ± 3.74 ng/ml vs 2.99 ± 2.36 ng/ml, p < 0.05; elevated RVSP: 4.44 ± 3.14 ng/ml vs 2.82 ± 2.64 ng/ml, p < 0.05). Conclusion. Galectin-3 may be related to the developmental process of skin sclerosis in dcSSc and of DU and pulmonary vascular involvements in total SSc.

IL-22, but not IL-17, Dominant Environment in Cutaneous T cell Lymphoma

Purpose: Both patients with cutaneous T-cell lymphoma (CTCL) and those with atopic dermatitis (AD) have pruritus, TH2-biased T cells, and a tendency to have bacterial infections, suggesting a common pathologic basis for these two diseases. Recently, interleukin (IL)-22–producing T cells were reported in skin of patients with AD. In this study, we investigated expression levels of TH22- and TH17-related molecules in lesional skin and sera isolated from patients with CTCL. Experimental Design: Skin biopsies and sera were collected from patients with CTCL or psoriasis and from healthy volunteers. Protein and mRNA expression levels of IL-22, IL-17A, IL-17F, IL-23p19, IL-10, IL-4, CCL20, CCR6, IL-8, and IL-20 were examined in lesional tissue and a subset of these molecules in sera. Phosphorylation of STAT3 was also assessed in lesional skin of CTCL and psoriasis by immunohistochemistry. Results: IL-22, IL-10, IL-4, CCL20, and CCR6 mRNA and protein levels, but not IL-17A, IL-17F, IL-23p19, IL-8, or IL-20, were significantly elevated in lesional skin of CTCL. Phosphorylation of STAT3 was detected in epidermis of CTCL skin. Moreover, serum IL-22, IL-10, and CCL20 levels were increased in CTCL and correlated with disease severity. Conclusions: Our results suggest that IL-22 is important in establishing the tumor microenvironment for CTCL. Enhanced expression of CCL20 may explain epidermal hyperplasia and migration of CCR6+ cells, such as Langerhans cells, into lesional skin. Relatively low expression of IL-17 may explain the lack of neutrophils in lesions of CTCL, which correlates with bacterial infections that commonly occur in skin affected by CTCL. Clin Cancer Res; 17(24); 7529–38. ©2011 AACR.

Novel effects of diosgenin on skin aging

Extracts of Dioscorea coomposita or Dioscorea villosa are consumed as supplemental health foods at the time of climacteric. The extracts contain large amounts of the plant steroid, diosgenin. Here, we studied the safety and efficacy of diosgenin against skin aging at the time of climacteric. In vitro, diosgenin enhanced DNA synthesis in a human 3D skin equivalent model, and increased bromodeoxyuridine uptake and intracellular cAMP level in adult human keratinocytes. The increase of bromodeoxyuridine uptake by diosgenin was blocked by an adenylate cyclase inhibitor, but not by antisense oligonucleotides against estrogen receptor alpha, estrogen receptor beta or an orphan G-protein-coupled receptor, GPR30, indicating the involvement of cAMP but not estrogen receptor alpha, estrogen receptor beta or GPR30. In vivo, administration of diosgenin improved the epidermal thickness in the ovariectomized mice, a climacteric model, without altering the degree of fat accumulation. In order to examine the safety of diosgenin, diosgenin and 17beta-estradiol were administered to breast cancer-burdened mice. The results revealed that while 17beta-estradiol accelerated the tumor growth, diosgenin did not show this effect. Our finding, a restoration of keratinocyte proliferation in aged skin, suggests that diosgenin may have potential as a safe health food for climacteric.

Thymus and activation-regulated chemokine (TARC/CCL17) produced by mouse epidermal langerhans cells is upregulated by TNF-α and IL-4 and downregulated by IFN-γ

Thymus and activation-regulated chemokine (TARC/CCL17) is a Th2-type chemokine and its receptor CC chemokine receptor 4 (CCR4) is preferentially expressed on Th2 cells. Langerhans cells (LC) are immature dendritic cells (DC) in the epidermis of the skin and play vital roles in immune response. In this study, we investigated TARC expression by murine freshly isolated LC and 48 h cultured (mature) LC, and the regulation of TARC production in cultured LC by various cytokines. Murine LC was prepared using a panning method from BALB/c mice. RT-PCR was performed using fresh and cultured LC to evaluate TARC mRNA levels. ELISA was carried out using supernatant of cultured LC to calculate secreted TARC protein levels. TARC mRNA was strongly upregulated during maturation of murine LC. TARC production by murine LC was upregulated by TNF-alpha and IL-4 and downregulated by IFN-gamma, dose-dependently. Th1 and Th2 cytokines reciprocally regulate the production of Th2-type chemokine TARC by murine LC. Th2 cytokine microenvironments in skin may increase TARC production by mature LC, providing attraction of Th2 cells in skin. This may be an amplification circuit in Th2-dominant inflammatory skin disease like atopic dermatitis.

Association of the numbers of CD163+ cells in lesional skin and serum levels of soluble CD163 with disease progression of cutaneous T cell lymphoma

BACKGROUND Classically activated macrophages produce IL-12, IL-23, and TNF-α, whereas alternatively activated macrophages (M2 cells) produce IL-10 and express several receptors such as mannose receptor and CD163. Tumor-associated macrophages exhibit M2 phenotype, whose presence has been associated with poor prognosis in various tumors. OBJECTIVES To investigate distribution of CD163(+) cells in lesional skin and serum levels of soluble CD163 (sCD163) in patients with cutaneous T cell lymphoma (CTCL), atopic dermatitis (AD), or psoriasis. METHODS The numbers of CD163(+) and CD68(+) cells in lesional skin of CTCL, AD, or psoriasis, and in normal skin were examined by immunohistochemistry. Serum soluble CD163 (sCD163) levels were quantified by enzyme-linked immunosorbent assay. RESULTS The numbers of CD163(+) cells in lesional skin of CTCL, AD, or psoriasis were significantly larger than in normal skin. In CTCL, the numbers of CD163(+) or CD68(+) cells increased as more tumor cells infiltrated and they decreased after treatment with topical steroid and ultraviolet light. Moreover, CTCL patients with an increased number of CD163(+) cells showed worse prognosis. Serum sCD163 levels in patients with CTCL, AD, or psoriasis were significantly higher than those in normal controls. In CTCL patients, serum sCD163 levels significantly correlated with serum soluble interleukin-2 receptor and CCL17 levels. In AD patients, serum sCD163 levels correlated with serum IgE levels. CONCLUSION The numbers of CD163(+) cells in lesional skin and serum sCD163 levels were associated with disease progression of CTCL. Further study focusing on CD163(+) cells in CTCL lesional skin would be an interesting research field.

Polymorphisms of vitamin D receptor gene in Japanese patients with psoriasis vulgaris

We examined polymorphisms of vitamin D receptor (VDR) gene in Japanese patients with psoriasis vulgaris (PsV). We also studied the association between VDR gene polymorphisms and the response to vitamin D (VD) topical treatment in psoriatic patients. FokI, BsmI, ApaI and TaqI genotypes were determined by restriction fragment patterns in patients (n = 115) and controls (n = 69). In addition, 54 psoriatic patients were divided into two groups in terms of their response to VD (tacalcitol) topical treatment: non-responsive (n = 30) and responsive (n = 24) patients. The frequencies of B allele and t allele were lower in patients than in controls (9 vs. 19%: p < 0.01, 7 vs. 14%: p < 0.05, respectively). In regard to response to VD treatment, F allele was lower in non-responsive patients than in controls (47 vs. 64%, p < 0.05). We show that polymorphisms of VDR gene are associated with Japanese patients with PsV. Allelic variance in the VDR gene or other genes in linkage disequilibrium with this gene might predispose to the development of PsV.