Hiraku Suga

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.

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.

Prevalent LIPH founder mutations lead to loss of P2Y5 activation ability of PA-PLA1α in autosomal recessive hypotrichosis†

Autosomal recessive hypotrichosis (ARH) is characterized by sparse hair on the scalp without other abnormalities. Three genes, DSG4, LIPH, and LPAR6 (P2RY5), have been reported to underlie ARH. We performed a mutation search for the three candidate genes in five independent Japanese ARH families and identified two LIPH mutations: c.736T>A (p.Cys246Ser) in all five families, and c.742C>A (p.His248Asn) in four of the five families. Out of 200 unrelated control alleles, we detected c.736T>A in three alleles and c.742C>A in one allele. Haplotype analysis revealed each of the two mutant alleles is derived from a respective founder. These results suggest the LIPH mutations are prevalent founder mutations for ARH in the Japanese population. LIPH encodes PA‐PLA1α (LIPH), a membrane‐associated phosphatidic acid‐preferring phospholipase A1α. Two residues, altered by these mutations, are conserved among PA‐PLA1α of diverse species. Cys246 forms intramolecular disulfide bonds on the lid domain, a crucial structure for substrate recognition, and His248 is one amino acid of the catalytic triad. Both p.Cys246Ser‐ and p.His248Asn‐PA‐PLA1α mutants showed complete abolition of hydrolytic activity and had no P2Y5 activation ability. These results suggest defective activation of P2Y5 due to reduced 2‐acyl lysophosphatidic acid production by the mutant PA‐PLA1α is involved in the pathogenesis of ARH. Hum Mutat 31:1–9, 2010.

TLR4, rather than TLR2, regulates wound healing through TGF-β and CCL5 expression

BACKGROUND Toll-like receptors (TLRs) have a crucial role in early host defense against invading pathogens. Recent studies suggest that TLRs play important roles in non-infections inflammation and tissue repair and regeneration. OBJECTIVE To determine the roles of TLR2 and TLR4 in mouse wound healing using TLR2-deficient (TLR2(-/-)), TLR4-deficient (TLR4(-/-)), and TLR2/TLR4-deficient (TLR2/4(-/-)) mice. METHODS Open wounds made in TLR2(-/-), TLR4(-/-), and TLR2/4(-/-) mice were examined clinically and histologically. Cytokine expression in the wounded skin was also investigated. TGF-β production from macrophages stimulated by hyaluronan, a ligand for TLR2 and TLR4, was evaluated by real-time PCR. RESULTS Wound areas in TLR2(-/-), TLR4(-/-), and TLR2/4(-/-) mice were larger than wild-type mice both at days 3 and 7 after wounding, accompanied by decreased numbers of infiltrating macrophages in the dermis and decreased TGF-β and CCL5 mRNA expression in the wounded skin. Immunohistochemistry showed decreased numbers of macrophages expressing TGF-β and reduced CCL5 expression by keratinocytes in the wounded skin from TLR2(-/-), TLR4(-/-), and TLR2/4(-/-) mice compared to wild-type mice. Moreover, TGF-β production from macrophages induced by hyaluronan stimulation in vitro was significantly decreased in the absence of TLRs, especially TLR4. Interestingly, macrophages and wounded skin from TLR2(-/-) mice showed decreased TLR4 mRNA expression compared to wild-type mice, suggesting that the effect of TLR2 deficiency was at least partially dependent on decrease in TLR4. Topical application of TGF-β and CCL5 significantly improved wound healing in TLR-deficient mice. CONCLUSION TLR4, rather than TLR2, regulates wound healing through TGF-β and CCL5 expression.

Increased CCL18 expression in patients with cutaneous T‐cell lymphoma: association with disease severity and prognosis

Background  CC chemokine ligand (CCL) 18 is expressed by monocytes and dendritic cells (DCs), and has potent chemotactic activity for T cells, B cells and DCs. CCL18 expression is up‐regulated in lesional skin of atopic dermatitis and bullous pemphigoid, suggesting its important roles in the development of these skin diseases.

Serum Gastrin-Releasing Peptide Levels Correlate with Pruritus in Patients with Atopic Dermatitis

effectors of the Wnt pathway, i.e., c-myc and Skp2 were not expressed in KSCs by reverse transcription–PCR (Figure 1b). Further, probing cell lysates of WIF1-arrested keratinocytes in western blots revealed that Wnt3A/ WIF1 treatment resulted in increased p21 protein levels (Figure 2o) demonstrable quantitatively (Figure 2p). Thus, WIF1 may achieve its cell cycle arrest in keratinocytes at least in part through derepression of p21 transcription. In conclusion, we report that WIF1 is, to our knowledge, previously unreported as a marker of interfollicular KSCs, and that it inhibits cell cycle progression in human keratinocytes even in the presence of activating Wnt signals (Wnt3A). Although canonical Wnt signaling appears to be dispensable during development in the interfollicular epidermis (Huelsken et al., 2001; Nguyen et al., 2009), our data suggest that inhibition of Wnt signaling may be required for keeping interfollicular stem cells quiescent and differentiating cells from proliferating during homeostasis.

Serum IL-31 levels are increased in patients with cutaneous T-cell lymphoma.

RESULTS As previously reported (4), serum IL-31 levels were significantly higher in patients with AD (2.13 ± 0.26 pg/ ml) than those of healthy controls (0.94 ± 0.28 pg/ml; p < 0.01; Fig. 1a). In addition, serum IL-31 levels were significantly higher in patients with CTCL (3.19 ± 0.74 pg/ml) than those of healthy controls (p < 0.05; Fig. 1a). We subsequently examined serum IL-31 levels in CTCL patients with different types of skin lesions. Serum IL31 levels in patients with patch and plaque, tumour and erythroderma were 1.05 ± 0.30 pg/ml, 6.25 ± 2.11 pg/ml and 5.00 ± 1.46 pg/ml, respectively (Fig. 1b). Serum IL-31 levels in patients with tumour were extremely high, which were significantly higher than those with healthy controls (p < 0.01) and patients with patch and plaque (p < 0.05). Serum IL-31 levels in patients with erythroderma were also significantly higher than those in healthy controls (p < 0.01). Serum IL-31 levels in patients with stage I, stage II, stage III and stage IV were 0.95 ± 29 pg/ml, 3.97 ± 1.43 pg/ml, 2.07 ± 0.00 pg/ ml and 7.98 ± 2.56 pg/ml, respectively (Fig. 1c). Serum IL-31 levels in patients with stage IV were significantly higher than those with healthy controls and patients with stage I (p < 0.05). Serum IL-31 levels in patients with stage II were significantly higher than those with healthy controls (p < 0.05). We also found that serum IL-31 levels correlated significantly with serum sIL-2R and LDH levels (r = 0.43, p < 0.05 and r = 0.34, p < 0.05, respectively; Fig. 1d, e), which have been reported to reflect disease activity of CTCL (8, 9). Thus, serum IL31 levels correlate with disease activity of CTCL.

TOX expression in different subtypes of cutaneous lymphoma

Early cutaneous T cell lymphoma clinically and histologically resembles benign inflammatory skin diseases, which sometimes makes it difficult to reach a correct diagnosis. It is recently reported that thymocyte selection-associated high mobility group box factor (TOX) serves as a molecular marker for histological diagnosis of early-stage mycosis fungoides (MF). To examine whether TOX could be a marker of tumour cells in different types of cutaneous lymphoma, we investigated immunohistochemical staining for TOX with the lesional skin of patch, plaque, and tumour MF, Sézary syndrome (SS), lymphomatoid papulosis (LyP), primary cutaneous anaplastic large cell lymphoma (PCALCL), adult T cell leukemia/lymphoma (ATLL), peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS), atopic dermatitis (AD), and normal skin. TOX and CCR4 messenger RNA (mRNA) levels in lesional skin of MF/SS were also examined. Immunohistological staining showed that a high specific nuclear staining of TOX was observed at a high frequency in MF, SS, and PTCL, NOS. Tumour cells in LyP, PCALCL, and ATLL showed a slightly dim nuclear staining of TOX. TOX+ cells in MF and LyP expressed surface molecules characteristics of tumour cells in these diseases. Lesional skin of SS expressed higher levels of TOX mRNA, compared to normal skin or MF lesional skin. Moreover, TOX expression significantly correlated with CCR4 expression. TOX may be a specific marker for tumour cells in some types of cutaneous lymphoma.

CXCR3 Deficiency Prolongs Th1-Type Contact Hypersensitivity

Sensitization and challenge using dinitrofluorobenzene (DNFB) induce contact hypersensitivity (CHS) with Th1 cell infiltration, whereas those using FITC generate CHS with Th2 cell infiltration. In this study, we attempted to determine the role of CXCR3, a chemokine receptor, in Th1- and Th2-type CHS induced by DNFB or FITC using CXCR3-deficient (CXCR3−/−) mice. Ear swelling was prolonged after DNFB challenge in CXCR3−/− mice, which was accompanied by increased Th1 cytokines and decreased TGF-β and IL-10 expression at a late time point of CHS, whereas there was no significant difference between wild-type and CXCR3−/− mice in FITC-induced CHS. In Th1-type CHS, the number of regulatory T cells (Tregs) was decreased in the challenged ear of CXCR3−/− mice compared with that of wild-type mice, suggesting that CXCR3 would be important in migration of Tregs into the site of inflammation. Moreover, we examined the characteristics of CXCR3+ Tregs both in vitro and in vivo, revealing that CXCR3+ Tregs expressed high levels of TGF-β and IL-10 as well as IFN-γ compared with CXCR3− Tregs. When CXCR3−/− mice were injected with CXCR3+ Tregs, the prolonged ear swelling induced by DNFB was normalized. Taken together, our results suggest that CXCR3+ Tregs play a key role for quenching Th1-type CHS.

CCR4 is expressed on infiltrating cells in lesional skin of early mycosis fungoides and atopic dermatitis.

CCR4 is expressed on tumor cells of mycosis fungoides (MF) and Sézary syndrome (SS). In MF, most infiltrating cells in patches and plaques express CXCR3, while tumor cells express CCR4 in advanced stages. Poteligeo Test IHC (CCR4 staining kit) is a newly developed staining kit that can examine the presence of CCR4 expressed on tumor cells of adult T‐cell leukemia/lymphoma, peripheral T‐cell lymphoma and cutaneous T‐cell lymphoma before treatment of anti‐CCR4 antibody using paraffin‐embedded samples. In this study, we analyzed CCR4 expression in lesional skin of MF, SS, atopic dermatitis (AD) and psoriasis with this new kit. CCR4 was expressed on infiltrating cells in lesional skin of patch, plaque, tumor MF and SS, and the number of positive cells increased as the disease progressed. Immunohistochemistry with frozen sections also showed some positive cells scattered in the dermis, although the quality was not high enough to quantify positive cells. There were significant positive correlations between CCR4+ cells and serum lactate dehydrogenase levels. Interestingly, CCR4+ cells were also detected in AD skin, whose number was larger than that in psoriatic skin. Previous studies showed only scattered CCR4+ cells in skin samples by standard immunohistochemical staining. The new, sensitive CCR4 staining kit has revealed that CCR4 is expressed on infiltrating cells in lesional skin of early MF and AD as well as advanced MF and SS. These cells can be therapeutic targets for patients who are resistant to standard treatments.