CTLA-4 expression in T cells of patients with atopic dermatitis

Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4; CD152) is a surface molecule of activated T cells with sequence homologous to CD28, and may act as a negative regulator of T-cell activation. In murine animal models, cross-linkage of CTLA-4 molecules on the cell surface results in decreased T-cell proliferation, accompanied by increased interleukin (IL)-2 production and apoptosis. To clarify the activation of peripheral blood T cells, we studied the CTLA-4 expression in 32 patients with atopic dermatitis who visited our institution, and 19 normal children who visited for pre-operative laboratory examination were used as normal controls. Whole blood was obtained from all subjects and stained with anti-CD3, anti-CD4, anti-CD8 monoclonal antibodies (mAb). After erythrocyte lysis with lysing solution, the cells were stained with anti-CTLA-4 mAb, and stained cells were analysed by fluorescence-activated cell sorter (FACScan) flow cytometer. Intracellular expression of CTLA-4 was significantly upregulated in peripheral blood CD3+ T cells (36.8%), CD4+ T cells (21.7%) and CD8+ T cells (18.7%) of patients with atopic dermatitis, compared with normal control (18.3%, 9.7%, 9.8%; respectively). Furthermore, CTLA-4-positive CD3+ T cells in patients with severe atopic dermatitis were significantly higher compared with milder group (42.8% vs. 32.2%). However, no significant difference was obtained in CD4+ and CD8+ T cells. Mean percentage of T cells expressing CTLA-4 in patients with atopic dermatitis was higher than the control group. These observations suggest the possibility that the disease activity can be correlated with the CTLA-4 level.     

Determinants of total and specific IgE in infants with atopic dermatitis

ETAC (Early Treatment of the Atopic Child), a multi-centre predominantly European study to investigate the potential for cetirizine to prevent the development of asthma in infants with atopic dermatitis has completed enrolment: 817 children have been randomised to 18 months' treatment with either active or placebo and a subsequent 18 months of post-treatment follow-up. Results of the therapeutic effects will not be available for some time, but the study has provided an opportunity to investigate influences on sensitization to allergens in a large cohort of 1-2 years olds with already established atopic dermatitis, resident in different countries and in different environments.
The study shows that in infants with atopic dermatitis, raised serum total IgE has significantly different determinants from that a specific allergen sensitization. In infancy, increased total IgE is more affected by factors increasing risk of intercurrent infection and non-specific airway inflammation, such as environmental tobacco smoke exposure (p < 0.001) and the use of gas cookers (p=0.02). Specific allergen sensitization as represented by detectable IgE antibodies is influenced primarily by allergen exposure. In Sweden, low level exposure to allergens is associated with reduced specific allergen sensitization rates even though the infants already have atopic dermatitis.     

Milk and ovalbumin-specific IgG4 in childhood atopic eczema: serum levels in relation to dietary changes

Serum levels of cow milk-specific IgG₄ (IgG₄-milk) and ovalbumin-specific IgG₄ (IgG₄-ova) were found to be raised in a group of children with atopic eczema. Patients with the highest levels had IgE-mediated hypersensitivity to some foods but no correlation with IgG₄ results. Initial IgG₄ levels did not predict whether the eczema would improve after a diet eliminating cow milk, egg and some other foods. Changes in IgG₄-milk during double-blind milk challenges did not correlate with clinical changes in patient's eczema as measured by skin assessment. There seems to be no clinical value in measuring IgG₄ antibodies to milk and ovalbumin in children with atopic eczema, the high titres reflecting antigen response only.     

Expansion of activated eosinophils in infants with severe atopic dermatitis

Abstract   Background : There is increasing concern in Japan over infants with atopic dermatitis (AD) who present with severe systemic complications, such as hypoproteinemia, electrolyte disturbances, and delayed growth and development. They are often associated with extremely increased numbers of circulating eosinophils. However, the clinical significance of eosinophil expansion has not been thoroughly investigated.
Methods : This study attempted to determine the significance of eosinophilia and eosinophil activation in infant cases of AD by comparing multiple clinical parameters, indexes of eosinophil activation, and levels of serum cytokines. CD69 expression was determined by flow cytometry. The clinical severity of AD was graded by the severity SCORing of atopic dermatitis (SCORAD) method. Patients were classified into two groups, with and without CD69 on eosinophils. Nuclear lobes were evaluated under a microscopy. Serum levels of eosinophil-derived neurotoxin (EDN), interleukin (IL)-12, IL-18, IL-4, IL-5 and interferon (IFN)-γ were determined by enzyme-linked immunosorbent assay.
Results : Patients with CD69-positive eosinophils had significantly higher numbers of eosinophils and platelets, total IgE, and eosinophil nuclear lobes. They also showed growth failure, developmental delay, low serum albumin, and electrolyte disturbances. EDN and IL-18 levels were significantly increased in this group, but the levels of IL-4, IL-5 and IL-12 were not significantly different between the two groups. IFN-γ was not detectable in all patients with AD. Surface expression of CD69 indicates intense systemic allergic inflammation induced in severe cases of AD.
Conclusions : Evaluation of eosinophil activation and early therapeutic intervention is mandatory for the treatment of severe AD during infancy.     

The clinical significance of food specific IgE/IgG4 in food specific atopic dermatitis

Food is closely associated with the pathogenesis of atopic dermatitis. Food allergy is usually mediated by IgE antibody to specific food proteins and determination of specific IgE antibody is the basis of the common diagnostic test for food allergy. IgG4 have been reported as blocking antibody and the protective effects of blocking antibody may be clear in inhalant allergy. However, the role of IgG4 in food allergy is still a matter of debate. In this study, the clinical significance of food allergen-specific IgE/IgG4 in atopic dermatitis was investigated and compared with that of IgE. A total of 97 patients who fulfilled the diagnostic criteria for atopic dermatitis participated in this study. Skin prick test and allergy patch test were performed. Specific IgE and IgG4 concentration were measured using allergy protein chip, 'AllergyChip'. Double blinded placebo controlled food challenge test (DBPCFC) was performed for the diagnosis of allergy to milk, egg white, wheat, and soybean. DBPCFCs for milk, egg white, soybean, and wheat were performed. The positive rates were 31.7% (19/60) in milk, 36.7% (18/49) in egg white, 30.4% (7/23) in soybean, and 34.8% (8/23) in wheat. Mean IgE/IgG4 levels in DBPCFC (+) subjects is higher than those in DBPCFC (-) subjects in all food items studied. Of them, there were significantly different between two groups in egg white and wheat (Egg white in DBPCFC (+) vs. (-): 0.4 +/- 0.3 vs. 0.2 +/- 0.2, wheat in DBPCFC (+) vs. (-): 1.2 +/- 1.2 vs. 0.3 +/- 0.3, p < 0.05). Allergen-specific IgE/IgG4 may provide one of the clues to understand the mechanism of food allergy in atopic dermatitis. The present study suggests that protein microarray can be one of the useful methods to assess ongoing status of allergic diseases.     

血清特异性IgE和IgG检测在儿童特应性皮炎过敏原诊断中的应用

目的探讨血清特异性IgE和IgG检测在儿童特应性皮炎过敏原诊断中的应用和意义。方法对64例患特应性皮炎的儿童,采用酶联免疫方法检测血清中食物过敏原的特异性IgG,同时采用免疫印迹方法检测血清中食物过敏原和吸入性过敏原的特异性IgE。结果食物过敏原特异性IgG和特异性IgE的检测结果不一致(P<0.01),食物过敏原特异性IgG的总阳性率为93.75%,主要食物过敏原是牛奶和鸡蛋。食物过敏原特异性IgE的总阳性率为46.88%,主要食物过敏原是鸡蛋和鱼虾蟹。吸入性过敏原特异性IgE的总阳性率为34.38%,主要过敏原是尘螨和霉菌。在0～1岁的特应性皮炎患儿中,以食物过敏原特异性IgE阳性多见;1岁以上的患儿吸入性过敏原特异IgE阳性多见,同时合并呼吸道过敏症状增多(P均<0.05)。结论食物过敏原和吸入性过敏原均是引起儿童特应性皮炎的重要原因。联合测定食物过敏原的特异性IgE和特异性IgG是变态反应性皮肤病患儿诊断食物过敏原的有效方法。尽早采取有效的环境控制,对治疗儿童特应性皮炎和预防呼吸道过敏性疾病的发生非常重要。     

IL-4IL-5及IgE在儿童咳嗽变异性哮喘中的价值

目的：咳嗽变异性哮喘(CVA)是一种与气道炎症相关的疾病,有研究表明IL-4,IL-5与IgE的产生有相关性,而且与哮喘的形成有关,因此推测IL-4,IL-5在CVA发病中起重要作用。该文旨在观察IL-4,IL-5及IgE在咳嗽变异性哮喘中的诊断价值。方法：用酶联免疫吸附实验(ELISA法)检测咳嗽变异性哮喘患儿、哮喘急性发作期患儿、正常同龄儿童各30例外周血单个核细胞(PBMC)内IL-4,IL-5及血清IgE水平。结果：①咳嗽变异性哮喘患儿发作期PBMCIL-4为91.57±12.19ng/L、IL-5为13.28±0.31ng/mL,显著高于缓解期的74.68±11.54ng/L,6.53±0.28ng/mL及正常对照组70.32±18.16ng/L,5.29±0.36ng/mL,(均P<0.01),但缓解期及正常对照组间差异无统计学意义;②咳嗽变异性哮喘发作期患儿血清IgE水平为279.6±41.3KU/L,显著高于缓解期153.8±37.5KU/L,两组均显著高于正常对照组的90.6±44.8KU/L,(均P<0.01);③咳嗽变异性哮喘患儿发作期IL-4,IL-5及IgE水平与哮喘患儿发作期的92.21±3.12ng/L,15.11±1.37ng/mL,287.5±41.9KU/L之间相比差异无统计学意义。结论：联合检测单个核细胞内IL-4,IL-5及血清IgE水平对咳嗽变异性哮喘的诊断有重要价值;IL-4,IL-5可能在咳嗽变异性哮喘的发病机制中起重要作用;咳嗽变异性哮喘可能存在与哮喘相同的发病机制,是典型哮喘的前驱表现。     

Food hypersensitivity in two groups of children and young adults with atopic dermatitis evaluated a decade apart

There is an impression that children today are experiencing allergic reactions to an increasing variety of foods. We compared two separate groups of children and young adults with atopic dermatitis evaluated a decade apart and found no difference in sensitization rates or overall clinical reactivity to a variety of foods. Allergies to egg, milk, wheat, soy, peanut, tree nuts, and seafood continue to account for ≈ 90% of food‐allergic reactions over the past decade.     

Soluble E-selectin and soluble ICAM-1 levels as markers of the activity of atopic dermatitis in children

The expression of adhesion molecules is up-regulated in the skin of atopic dermatitis (AD) patients, and the levels of the soluble adhesion molecules sE-selectin and sICAM-1 have been reported to reflect the endothelial activation in the skin of AD patients. The objective of the study was to investigate the relationship between symptom score and levels of sE-selectin, sICAM-1 and sVCAM-1 before and after 2 weeks of treatment. Eighteen children with an exacerbation of AD were admitted and treated with corticosteroid dilutions under occlusive wet dressings (wet-wrap treatment). Symptom score (objective SCORAD) and levels of sE-selectin, sICAM-1, and sVCAM-1 were assessed before and after 2 weeks of treatment. A significant correlation between the objective SCORAD before treatment and the level of sE-selectin (p < 0.05), but not the level of sICAM-1 (p = 0.7) or sVCAM-1 (p = 0.5) was observed. The treatment resulted in a high degree of remission, which was reflected by a significant decrease in the level of sICAM-1 (p < 0.01), whereas there was only a trend in the level of sE-selectin to decrease (p = 0.08). The level of sE-selectin after 2 weeks of treatment still correlated significantly with the objective SCORAD before treatment (p < 0.005). Soluble E-selectin is a relative objective marker for the severity of AD. SCORAD is a treatment-sensitive symptom of AD, whereas E-selectin may be a more stable underlying systemic representation of AD.     

Serum concentrations of CCR4 ligands in relation to clinical severity of atopic dermatitis in Egyptian children

T helper 2 (Th2) lymphocytes, the key effector cells in pathogenesis of atopic dermatitis (AD), express CCR4 receptors. CCR4 ligands (macrophage-derived chemokine ‘MDC’ and thymus and activation-regulated chemokine ‘TARC’) direct trafficking and recruitment of Th2 cells into lesional skin in AD. These chemokines appear to be useful inflammatory markers for assessing severity of AD in adults. However, the same results have not been replicated in children. Therefore, we were stimulated to elucidate the expression of CCR4 ligands in children with AD and their relation to clinical disease severity. To investigate this, serum concentrations of CCR4 ligands were determined in 60 children, of whom 30 had AD and 30 were healthy matched subjects. Patients were classified into mild (n = 8), moderate (n = 12) and severe (n = 10) according to the objective scoring AD (obj-SCORAD) index. Serum concentrations of MDC and TARC were significantly increased in children with AD (2697 ± 982.6 pg/ml and 945.5 ± 494.7 pg/ml, respectively) compared with controls (357.2 ± 233.2 pg/ml and 214.2 ± 116.6 pg/ml, respectively, p < 0.0001). Serum levels of both chemokines went hand in hand with disease severity as they were significantly higher in severe than moderate and in moderate than mild AD. In addition, they correlated positively with obj-SCORAD (r = 0.99 for both, p < 0.0001). Furthermore, both chemokines had significant positive correlations to blood eosinophil counts and serum immunoglobulin E. In conclusion, serum CCR4 ligands may be useful inflammatory markers for assessing AD severity in children. Further studies may pave way for CCR4 ligands antagonism among the adjuvant therapeutic strategies of AD.     

Montelukast in the treatment of children with moderate-to-severe atopic dermatitis:A pilot study

The primary action of leukotrienes includes contraction of human airway muscle, chemotaxis, and increased vascular permeability, with secondary effects of inhibiting allergen-induced early and late responses. Although there is limited available information and research regarding leukotrienes in atopic dermatitis (AD), there is evidence to support their role in the pathogenesis of the disease. We conducted a pilot study to test the efficacy of montelukast, a cysteinyl-leukotriene-1 receptor antagonist, in 15 patients (6–16 years of age) with moderate-to-severe AD, using a randomized double-blind placebo-controlled crossover study. These patients had chronic moderate-to-severe AD, despite being on conventional therapy. They were randomized either to placebo for 4 weeks and then the study drug for 4 weeks, or vice versa. There was a 2-week run-in period for all participants before commencement of the study, and a 2-week washout before crossover. At enrollment and on each follow-up visit, every patient was assessed by a single observer and objectively scored for disease extent and severity. A subjective score was given for the impact of eczema on daily living. There was statistical improvement in patents on active treatment compared with placebo in the severity of AD (p < 0.05). Our findings suggest that leukotriene receptor antagonist as an adjunct treatment has an anti-inflammatory effect on moderate-to-severe AD. A larger trial is needed to ascertain its efficacy fully.     

Leukotriene B4 and C4 generation by blood leukocytes after ex vivo stimulation by Ca-ionophore and opsonized zymosan in children with atopic dermatitis

The ex vivo release of leukotrienes B₄ (LTB₄) and C₄ (LTC₄) from the leukocytes of children with atopic dermatitis (AD) was evaluated after stimulation with Ca-ionophore and opsonized zymosan and compared with that of control children of similar ages. The blood eosinophil counts and total serum IgE levels in AD children were significantly higher than those in control children. The production of LTC₄, but not LTB₄, was significantly higher in AD children than in control children. There was a significant correlation between the relative blood eosinophil count and LTC₄ generation after stimulation with both Ca-ionophore and opsonized zymosan in all subjects. Calculations of the amount of LTC₄ produced per eosinophilic cell showed that there was no significant difference between cells from AD children and control children in terms of their ability to produce LTC₄. These findings suggest that the enhanced LTC₄ generation is due to increased numbers of eosinophils rather than to enhanced releasability of these cells.     

儿童特应性皮炎严重度与维生素D水平的相关性

目的探讨儿童特应性皮炎(AD)疾病严重程度与维生素D水平的相关性。方法纳入152例AD患儿,以AD严重程度评分(SCORAD)评估AD严重度,液相色谱-串联质谱法检测血清25-羟维生素D[25 (OH)D],分析AD严重程度与血清25(OH)D水平的相关性。结果 152例AD患儿中,男81例、女71例,中位年龄3.5岁。轻度、中度、重度AD患儿分别为51例(33.6%)、80例(52.6%)、19例(12.5%)。血清25(OH)D充足55例(36.2%),不足65例(42.8%),缺乏32例(21.1%)。AD患儿SCORAD评分与血清25(OH)D水平无显著相关性(r=-0.047,P=0.567),与血清总IgE呈显著正相关(r=0.244,P=0.003),与血嗜酸性粒细胞比例呈显著正相关(r=0.239,P=0.004)。结论 AD儿童中血清维生素D缺乏和不足者较多,但AD的严重程度与血清25(OH)D水平无显著相关性。     

Comparison of fecal microflora in children with atopic eczema/dermatitis syndrome according to IgE sensitization to food

Atopic eczema/dermatitis syndrome (AEDS) commonly often arises during early infancy. In several intervention studies a beneficial influence on AEDS course of certain intestinal bacteria, administered as 'probiotics', has been described. To evaluate the possible role of the natural intestinal microflora in children with allergic eczema/dermatitis syndrome regarding immediate type hypersensitivity to food allergens, children with food allergy (AAEDS, n = 68) have been compared with children without detectable food allergy (NAEDS, n = 25). All children (n = 93) in preschool age, mean age of 2.6 (+/-1.8) years, diagnosed with AEDS who were treated as inpatients in 2003 in a dermatological hospital were included. The correlation between fecal microflora, parasites and specific immunoglobulin E (IgE) antibodies against common food allergens was analyzed. A similar composition of intestinal microflora in children with AAEDS and NAAEDS was found. The food allergens that were most frequently detected were egg white, cow milk, casein, peanut and hazelnut. Furthermore, a significant association between IgE sensitization against important food allergens and components of the fecal microflora could not be demonstrated. With aging changes occur in the intestinal microbiota [Proteus/Klebsiella and age (rho = -0.607) and Enterococcus and age (rho = -0.428)]. In two subjects of the AAEDS group Blastocystis hominis was found. The composition of natural intestinal microflora in children with AAEDS and NAAEDS was similar. Hence, there is no evidence of a role of the intestinal microflora with regard to the development of infant (food) allergy in children with AEDS. The possible consequences for allergic diseases later in life require further investigation.     

Neuroendocrine and circadian aspects (melatonin and β-endorphin) of atopic dermatitis in the child

Atopic dermatitis (AD) is a disease of increasing incidence among paediatric patients. Among the factors involved in its pathogenesis is the alteration of the immune response, and so the objective of this study was to evaluate the involvement of certain neuroendocrine factors with immune properties in the development of the disease. Fifty-five subjects were selected and divided into the following three groups: healthy subjects, those diagnosed with symptomatic AD and those with asymptomatic AD. Plasma levels of melatonin and beta-endorphins were measured by radioimmunoassay, in serum samples obtained at 9 am and 9 pm, with two samples being obtained from each of the patients and controls. In the phases of AD outbreaks, there is a reduction in the serum levels of both melatonin and beta-endorphin. In the case of melatonin, the difference is statistically significant only during the day, although nocturnal levels are greater for both hormones. In AD, a central neuroendocrine dysfunction may be a primary pathogenic event. Our hypothesis is that the physiological nocturnal peak of melatonin due to pineal gland production may mask the decline of melatonin of possibly extrapineal (immunological) origin during episodes of dermatitis outbreaks. Further studies are required, particularly of neurovegetative and hormonal aspects, to better define this process. Such a definition would also be of therapeutic interest.     

Positive skin and oral challenge responses to potato and occurrence of immunoglobulin E antibodies to patatin (Sol t 1) in infants with atopic dermatitis

The clinical significance and molecular specificity of hypersensitivity reactions to raw and cooked potatoes remain ambiguous. We therefore investigated the clinical hypersensitivity to raw and cooked potato in infants suspected to have potato allergy and compared the findings with the occurrence of immunoglobulin E (IgE) antibodies to patatin (Sol t 1), characterized as the primary allergen of potato. Twelve infants (10 to 24 months of age) suffering from atopic dermatitis (AD) and suspected to have adverse reactions to potato, were examined. As a skin exposure test we used rubbing with both raw and cooked potato, and used open oral challenge with cooked potato for 7 days. A special eczema scoring system (SCORAD) was used to assess the severity of symptoms and signs of AD. Skin-prick tests (SPTs) were performed with raw potato and natural Sol t 1, and serological studies included measurement of total serum IgE and IgE antibodies to Sol t 1, and potato radioallergosorbent testing (RAST). The skin-rubbing test with raw potato was positive in seven (58%) and the oral challenge positive in eight (67%) infants. One infant presented with an immediate reaction and seven with a delayed reaction, i.e. exacerbation of AD, after oral challenge responses to cooked potato. Nine (75%) infants had IgE antibodies to Sol t 1 in enzyme-linked immunosorbent assay (ELISA), and SPT to natural Sol t 1 was positive in six (50%) potato-allergic infants. In conclusion, we observed positive challenge responses to both raw and cooked potato in food-allergic atopic infants. The presence of IgE antibodies and concomitant positive SPTs to the heat-stable potato allergen, Sol t 1, suggest that cooked potato can be an allergenic food for infants suffering from AD.