Levels of immunoglobulin E specific to the major food allergen and chemokine (C-C motif) ligand (CCL)17/thymus and activation regulated chemokine and CCL22/macrophage-derived chemokine in infantile atopic dermatitis on Ishigaki Island.

Atopic dermatitis (AD) is a multifactorial T-helper (Th)2-mediated skin disease frequently associated with elevated serum immunoglobulin (Ig)E and food allergy is also a Th2- and IgE-mediated adverse immunological reaction. Our previous study indicated the relation of egg allergy history and disease severity of AD. Thus, the purpose of the study was to investigate the levels of IgE specific to major food allergens (egg, milk, wheat) and Th2 chemokines (chemokine [C-C motif] ligand [CCL]17/thymus and activation regulated chemokine [TARC] and CCL22/macrophage-derived chemokine [MDC]) and the relationship between them. A total of 743 nursery school children were enrolled. Dermatologist-based physical examination and a questionnaire survey were also conducted. Significantly increased levels of disease severity markers (CCL17/TARC and CCL22/MDC) were confirmed in children with AD. The levels of CCL22/MDC in all of the children were markedly high compared with those reported in adults. IgE specific to egg white, ovomucoid, wheat and mite antigen were significantly higher in the AD group than in the non-AD group. Among them, IgE specific to egg allergens were well associated with disease severity markers, and IgE specific to ovomucoid seemed particularly well correlated with the presence of egg allergy history. In conclusion, the markedly high level of CCL22/MDC in children as compared with those reported in adults may partly explain the AD-prone nature of children and their spontaneous remission afterwards. Mild but significant correlation of IgE specific to egg allergens and Th2 chemokines may explain correlation of disease severity and comorbidity of egg allergy in our previous study.

Incidence, serum IgE and TARC/CCL17 levels in atopic dermatitis associated with other allergic diseases: an update from the Ishigaki cohort.

Population cohort studies are important for understanding the current status of the target disease and its relation to comorbidity, gender, age, or environmental factors. To better understand atopic dermatitis (AD) and its related diseases, we initiated in 2001 a population cohort study of nursery school children from Ishigaki Island, Okinawa, Japan. The cohort study comprised a dermatologist-based physical examination, questionnaire administration, and blood sample analysis. The mean prevalence of AD was 6.3%. Questionnaire-based bronchial asthma and egg allergy in the children and paternal and sibling AD were statistically significant risk factors for AD. Boys with AD had a high incidence of asthma that was coexistent with a high serum total immunoglobulin E level. Also a high incidence of egg allergy was associated with greater AD severity as assessed by TARC/CCL17.

VP2118 has major roles in Vibrio parahaemolyticus response to oxidative stress.

BACKGROUND: Reactive oxygen species (ROS), including superoxide anion radical, induce chronic risk of oxidative damage to many cellular macromolecules resulting in damage to cells. Superoxide dismutases (SODs) catalyze the dismutation of superoxide to oxygen and hydrogen peroxide and are a primary defense against ROS. Vibrio parahaemolyticus, a marine bacterium that causes acute gastroenteritis following consumption of raw or undercooked seafood, can survive ROS generated by intestinal inflammatory cells. However, there is little information concerning SODs in V. parahaemolyticus. This study aims to clarify the role of V. parahaemolyticus SODs against ROS. METHODS: V. parahaemolyticus SOD gene promoter activities were measured by a GFP reporter assay. Mutants of V. parahaemolyticus SOD genes were constructed and their SOD activity and resistance to oxidative stresses were measured. RESULTS: Bioinformatic analysis showed that V. parahaemolyticus SODs were distinguished by their metal cofactors, FeSOD (VP2118), MnSOD (VP2860), and CuZnSOD (VPA1514). VP2118 gene promoter activity was significantly higher than the other SOD genes. In a VP2118 gene deletion mutant, SOD activity was significantly decreased and could be recovered by VP2118 gene complementation. The absence of VP2118 resulted in significantly lowered resistance to ROS generated by hydrogen peroxide, hypoxanthine-xanthine oxidase, or Paraquat. Furthermore, both the N- and C-terminal SOD domains of VP2118 were necessary for ROS resistance. CONCLUSION: VP2118 is the primary V. parahaemolyticus SOD and is vital for anti-oxidative stress responses. GENERAL SIGNIFICANCE: The V. parahaemolyticus FeSOD VP2118 may enhance ROS resistance and could promote its survival in the intestinal tract to facilitate host tissue infection.

Periostin promotes chronic allergic inflammation in response to Th2 cytokines.

Allergic inflammation triggered by exposure of an allergen frequently leads to the onset of chronic inflammatory diseases such as atopic dermatitis (AD) and bronchial asthma. The mechanisms underlying chronicity in allergic inflammation remain unresolved. Periostin, a recently characterized matricellular protein, interacts with several cell surface integrin molecules, providing signals for tissue development and remodeling. Here we show that periostin is a critical mediator for the amplification and persistence of allergic inflammation using a mouse model of skin inflammation. Th2 cytokines IL-4 and IL-13 stimulated fibroblasts to produce periostin, which interacted with αv integrin, a functional periostin receptor on keratinocytes, inducing production of proinflammatory cytokines, which consequently accelerated Th2-type immune responses. Accordingly, inhibition of periostin or αv integrin prevented the development or progression of allergen-induced skin inflammation. Thus, periostin sets up a vicious circle that links Th2-type immune responses to keratinocyte activation and plays a critical role in the amplification and chronicity of allergic skin inflammation.

Expression of CD10 predicts tumor progression and unfavorable prognosis in malignant melanoma.

BACKGROUND: CD10 expression in malignant melanoma (MM) has been reported to increase according to tumor progression and metastasis; however, its association with patient outcome has not been clarified. OBJECTIVE: We examined the immunohistochemical expression of CD10 in MM to determine whether or not it could serve as a marker for tumor progression and prognosis. METHODS: A total of 64 formalin-fixed, paraffin-embedded samples of primary MM were immunostained for CD10. Similarly, 40 samples of melanocytic nevus and 20 of metastatic MM were analyzed for comparison. The following clinicopathologic variables were evaluated: age, gender, histologic type, tumor site, Breslow thickness, Clark level, the presence or absence of ulceration and tumor-infiltrating lymphocytes, and survival. Statistical analyses were performed to assess for associations. Several parameters were analyzed for survival using the Kaplan-Meier method and Cox proportional hazards model. RESULTS: Immunohistochemical analysis revealed that 34 of 64 cases (53%) of primary MM expressed CD10, compared with 15 of 20 cases (75%) of metastatic MM and only 4 of 40 cases (10%) of nevus. There was a significant positive relationship between CD10 expression and Breslow thickness, Clark level, and ulceration. Univariate analysis revealed 4 significant factors for shorter survival periods: CD10 expression, high Breslow thickness, high Clark level, and the presence of ulceration (P < .01 each). In multivariate analysis, CD10 expression was revealed to be a statistically significant and independent prognostic factor. LIMITATIONS: The major limitation was the small sample size. CONCLUSION: CD10 expression may serve as a progression marker and can predict unfavorable prognosis in patients with MM.

CD10 expressed by fibroblasts and melanoma cells degrades endothelin-1 secreted by human keratinocytes.

Endothelin-1 (ET-1) is a potent multifunctional peptide linked to wound healing, pigmentation, carcinogenesis, and fibrosclerotic processes in the skin. Whereas ET-1 was thought to be digested by receptor-mediated endocytosis, it is also reported to be biochemically degraded by the neutral endopeptidase CD10 using kidney homogenates. Although keratinocytes (KC) and fibroblasts (Fb) are sources of both ET-1 and CD10, respectively, there is no report investigating the direct association between CD10 expression and its function in relation to ET-1 degradation in the skin. CD10 expression in melanoma cells is associated with clinical prognosis, suggesting an important role in the invasive and metastatic potential of melanoma cells. Here, cultured KC produced much higher amounts of ET-1 than did cultured Fb or melanoma cells. In contrast, KC and A375 melanoma cells did not express CD10, while Fb, SK-MEL-28 and G361 melanoma cells constitutively expressed CD10. KC-derived ET-1 was down-modulated by both CD10-positive Fb and CD10-positive melanoma cells, and the inhibition was partially reversed under substitution conditions using CD10-knockdown Fb or CD10-knockdown melanoma cells. This indicates that CD10 on cultured Fb and melanoma cells is biochemically active in the degradation or down-modulation of ET-1 secreted from KC. These findings may lead to better understanding of skin homeostasis and of the malignant potential of melanoma.

Loss of Wnt-5α is associated with an invasive phenotype of extramammary Paget's disease.

BACKGROUND: The Wnt (wingless-type MMTV integration site) gene family encodes secretory signaling molecules that play a diverse biological role in the regulation of normal and pathological processes, including cell growth, differentiation and oncogenesis. However, the role of Wnt genes in the development of extramammary Paget's disease remains unknown. OBJECTIVE: To investigate the expression of Wnt-1, Wnt-5α and their downstream genes, ß-catenin and c-Myc, in extramammary Paget's disease. METHODS: Paraffin-embedded specimens of extramammary Paget's disease (33 specimens from 22 patients), including 7 specimens with dermal invasion and 4 with lymph node metastasis, were examined immunohistochemically for Wnt-1, Wnt-5α, ß-catenin and c-Myc. Seven normal genital skin specimens served as controls. RESULTS: The expression levels of Wnt-1 and ß-catenin in extramammary Paget's disease were significantly correlated with each other; however, their expression levels in the invasive extramammary Paget's disease were similar to those of wholly intraepithelial extramammary Paget's disease. Nuclear expression of c-Myc was significantly higher in the invasive extramammary Paget's disease in comparison with intraepithelial extramammary Paget's disease. Interestingly, the expression of Wnt-5α in invasive extramammary Paget's disease was significantly downregulated compared to wholly intraepithelial extramammary Paget's disease. CONCLUSION: The Wnt-1/ß-catenin pathway may not play an important role in the progression of extramammary Paget's disease. The loss of Wnt-5α, however, may play a role in the invasiveness of extramammary Paget's disease.

Decrease in circulating Th17 cells correlates with increased levels of CCL17, IgE and eosinophils in atopic dermatitis.

BACKGROUND: Clinical significance of circulating CD4(+) T cell subsets, including T-helper (Th)1, Th2, Th17 and regulatory T (Treg) cells, in patients with atopic dermatitis (AD) remains unclear. No previous studies have simultaneously evaluated the four T cell subset profiles in AD. OBJECTIVE: The aim of the present study was to explore whether the percentage of these four subsets of CD4(+) T cells correlate to the severity parameters of AD patients. METHODS: Intracellular expression of interferon (IFN)-γ, interleukin (IL)-4, IL-17 and forkhead box P3 (Foxp3) in CD4(+) T cells was evaluated in peripheral blood mononuclear cells from normal controls and patient with AD as well as with chronic eczema using a flow cytometer. Serum CCL17 levels were measured as an objective severity parameter of AD together with percentage of eosinophils and serum IgE levels. RESULTS: In AD patients, the number of Th1 (IFN-γ(+)) and Th17 (IL-17(+)) subsets was significantly decreased, but that of Th2 (IL-4(+)) and Treg (Foxp3(+)) subsets was similar to that of normal controls. The T cell subset profiles of patients with chronic eczema were not different with those of normal controls. The frequency of Th17cells, particularly that of the IFN-γ(nega)IL-17(+) subset, showed a significant negative correlation with CCL17, IgE and eosinophil levels in AD patients. This was, however, not the case in Th1, Th2 and Treg cells. CONCLUSION: Decreased circulating Th17 cells might contribute to activity of AD.

Cathepsin K-upregulation in fibroblasts promotes matrigel invasive ability of squamous cell carcinoma cells via tumor-derived IL-1α.

BACKGROUND: Cathepsin K (CTSK), a cysteine protease with strong collagenolytic properties, is involved in extracellular matrix turnover. In the previous studies, CTSK expression was detected in peritumoral fibroblasts (Fbs) around squamous cell carcinoma (SCC), but not in those surrounding benign epidermal tumors. However, the mechanism governing CTSK expression in epidermal tumors remains unclear. OBJECTIVE: To study the regulatory mechanisms of fibroblastic CTSK expression in the SCC-stromal interaction. METHODS: We examined dynamic interactions of Fbs with tumorigenic SCC cells (A431 and A253) or normal human keratinocytes. RESULTS: SCC cells and normal keratinocytes did not synthesize CTSK, while Fbs constitutively expressed CTSK. When cocultured, SCC cells upregulated fibroblastic CTSK expression more potently than did normal keratinocytes, which was mainly attributable to SCC-derived IL-1α. Coculturing Fbs with SCC cells significantly augmented the matrigel invasive ability of SCC cells, which was downregulated when cocultured with CTSK knockdown Fbs or in the presence of neutralizing anti-IL-1α antibody. CONCLUSION: The CTSK-upregulated Fbs generated by SCC-derived IL-1α may play a crucial role in the progression and invasion of SCC.

Are lifetime prevalence of impetigo, molluscum and herpes infection really increased in children having atopic dermatitis?

BACKGROUND: Cutaneous infections such as impetigo contagiosum (IC), molluscum contagiosum (MC) and herpes virus infection (HI) appear to be associated with atopic dermatitis (AD), but there are no reports of concrete epidemiological evidence. OBJECTIVE: We evaluated the association of childhood AD with these infections by conducting a population-based cross-sectional study. METHODS: Enrolled in this study were 1117 children aged 0-6 years old attending nursery schools in Ishigaki City, Okinawa Prefecture, Japan. Physical examination was performed by dermatologists, and a questionnaire was completed on each child's history of allergic diseases including AD, asthma, allergic rhinitis and egg allergy, and that of skin infections including IC, MC and HI, as well as familial history of AD. RESULTS: In 913 children (AD; 132), a history of IC, MC or HI was observed in 45.1%, 19.7%, and 2.5%, respectively. Multiple logistic regression analysis revealed that the odds of having a history of IC were 1.8 times higher in AD children than in non-AD children. Meanwhile, a history of MC was significantly correlated to the male gender, but not to a personal history of AD. As for HI, we found no correlated factors in this study. CONCLUSIONS: The lifetime prevalence of IC was indeed higher in young children with a history of AD.

CD10-bearing fibroblast inhibits matrigel invasive potency of interleukin-1α-producing squamous cell carcinoma by diminishing substance P levels in the tumor microenvironment.

CD10 is a neutral endopeptidase, which cleaves various peptide substrates including substance P. CD10 expression has been detected in peritumoral fibroblasts (Fb) within the invasive area of various cancers such as squamous cell carcinoma (SCC). However, the biological significance of CD10-bearing Fb remains largely unknown. We examined dynamic interactions of Fb with tumorigenic A431 SCC cells or non-tumorigenic HaCaT squamous cells. The SCC and HaCaT cells did not synthesize CD10, while Fb constitutively expressed CD10. When co-cultured, SCC markedly upregulated fibroblastic CD10 expression compared with HaCaT, which was mainly attributable to SCC-derived interleukin-1α (IL-1α). Both SCC and Fb autonomously secreted substance P, which eventually enhanced the invasive capacity of SCC in a matrigel invasion assay by upregulating matrix metalloproteinase (MMP)-1 and MMP-2, but not MMP-9. Transfection of siRNA for CD10 successfully knocked down the CD10 expression in Fb (CD10ND-Fb). In the presence of CD10ND-Fb, substance P levels in supernatants as well as MMP production and the invasive potency of SCC were significantly augmented compared with control scramble RNA-transfected Fb. We also transfected CD10 vector to Fb and found that the matrigel invasive ability of SCC cells was downregulated co-cultured with CD10 vector-transfected Fb rather than empty vector-transfected Fb. In conclusion, the CD10-bearing Fb generated by SCC-derived IL-1 inhibited the invasive capacity of SCC by diminishing the microenvironmental concentration of substance P.

Aberrant expression of tenascin-c and neuronatin in malignant peripheral nerve sheath tumors.

Development of neurofibroma (NF) and its malignant counterpart, malignant peripheral nerve sheath tumor (MPNST), is a hallmark of type I neurofibromatosis (NF1). Newly identified glycoprotein neuronatin (Nnat) is predominantly expressed in the fetal central and peripheral nervous systems and is gradually diminished according to the neural maturation. However, its expression in NFs and MPNSTs is unknown. Since an overexpression of tenascin-C (Tn-C), an extracellular matrix component, has been observed in neural malignancies, we investigated the immunohistological expressions of Nnat and Tn-C in NFs and MPNSTs, and compared their expression with that of the proliferation marker Ki-67 to possibly distinguish MPNSTs from ordinal NFs. Standard immunohistological procedure was performed for Nnat, Tn-C and Ki-67 in 9 sporadic NFs, 15 diffuse NFs (NF1), 15 plexiform NFs (NF1) and 6 MPNSTs (NF1), as well as 5 normal skins. All of the MPNSTs showed positive staining for Nnat, Tn-C and Ki-67, in sharp contrast to completely negative staining in all sporadic or NF-1-derived NFs. The aberrant expression of Nnat and Tn-C was a useful marker for distinguishing MPNSTs from benign NFs.

Scratching behavior does not necessarily correlate with epidermal nerve fiber sprouting or inflammatory cell infiltration.

BACKGROUND: Increased sprouting of epidermal nerve fibers of lesional skin are thought to be associated with persistent pruritus in chronic inflammatory dermatitis such as atopic dermatitis as supported by a murine study using tacrolimus (or FK506: FK) which was shown to inhibit both epidermal sprouting of nerves and scratching behavior or by immunohistochemical observations of lesional skin in the patients with atopic dermatitis or prurigo, etc. OBJECTIVES: To examine a mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 1/2 (MEK1/2) inhibitor (CX-659S: CX) for a possible anti-pruritic property in vivo since some MEK1/2 inhibitors have been reported to inhibit neurite growth in vitro. METHODS: CX, FK and corticosteroids (betamethasone valerate: BV) were topically applied on inflamed skin in a mouse model of chronic dermatitis using repetitive hapten painting to examine anti-pruritic property and anti-inflammatory effects. Scratching behaviors were assessed using MicroAct automatic measuring system, and epidermal sprouting of nerves and skin inflammation was assessed histologically. RESULTS: FK significantly decrease scratching behavior, but CX and BV failed to do so despite of their ability to significantly inhibit epidermal nerve fiber sprouting and skin inflammation, respectively. In addition, CX+BV mixture synergistically inhibited epidermal nerve fiber sprouting and skin inflammation even more potently than FK without decreasing scratching behavior. CONCLUSIONS: These findings suggest that the scratching behavior does not necessarily correlate with epidermal nerve fiber sprouting or inflammatory cell infiltration.

Differential expression of phosphorylated extracellular signal-regulated kinase 1/2, phosphorylated p38 mitogen-activated protein kinase and nuclear factor-kappaB p105/p50 in chronic inflammatory skin diseases.

The keratinocytes actively participate in the cutaneous immune responses. Dysregulation and abnormal expression of inflammatory mediators or their receptors in keratinocytes are relevant to the pathogenesis of chronic inflammatory skin diseases. The mechanism of long-lasting inflammatory processes is related with the activation of nuclear factor (NF)-kappaB and mitogen-activated protein kinase (MAPK), which play a crucial role in the immune responses. There are potential interaction points between these two pathways. The aim of this study is to investigate the differences in expression levels and distributions of phosphorylated extracellular signal-regulated kinase (ERK)1/2, phosphorylated p38 MAPK and NF-kappaB p105/p50 in chronic inflammatory skin diseases. An immunohistochemical staining technique was employed to measure the expression of these molecules in 25 cases of lichen planus, 22 cases of psoriasis, 26 cases of chronic eczema, seven cases of prurigo and seven cases of normal skin. We observed that the expression of phosphorylated ERK1/2, phosphorylated p38 MAPK and NF-kappaB p105/p50 was significantly more augmented in the lesional epidermis of all the inflammatory skin diseases than those in normal skin (P < 0.05), and the number of positive keratinocytes was significantly more in lichen planus than that in other inflammatory diseases (P < 0.001). Moreover, the positive keratinocytes of these three molecules were more widely distributed in the entire layer of the epidermis in lichen planus than those in other diseases. We concluded that ERK1/2, p38 MAPK and NF-kappaB p105/p50 might play important roles in the pathophysiology of chronic inflammatory skin diseases.