Serum cytokine levels in atopic dermatitis

Association between CCL5, CCL11, and CCL17 polymorphisms and atopic dermatitis risk: A systematic review and meta-analysis

BACKGROUND

Atopic dermatitis (AD) is a common and recurrent inflammatory disease with strong genetic susceptibility. The abnormal production of chemokines plays an important role in the occurrence and development of AD.

METHODS

A comprehensive online literature search was performed in databases of China National Knowledge Infrastructure, Wanfang, VIP China Science and Technology Journal Database, China Biomedical Literature Database, PubMed, Embase and Cochrane Library to retrieve relevant articles published from January 2000 to October 2022. The odds ratio (OR) with its 95% confidence interval (CI) was employed to calculate this relationship.

RESULTS

A total of 7 studies were finally screened out, including 1316 AD patients and 1099 controls. There were 3 studies for CC chemokine ligand 5 (CCL5) polymorphisms, 2 for CCL11 polymorphisms, and 2 for CCL17 polymorphisms, respectively. The meta-analysis revealed a significant association between the CCL5 - 403G/A polymorphism and AD under the allelic model (A vs G: OR = 1.25, 95% CI = 1.02-1.52, P = .03), heterozygous model (AG vs GG: OR = 1.40, 95% CI = 1.08-1.80, P = .01) and dominant model (AA + AG vs GG: OR = 1.38, 95% CI = 1.08-1.76, P = .01) in a fixed-effect model. The allelic model (G vs C: OR = 1.46, 95% CI = 1.07-1.98, P < .01) and dominant model (GG + GC vs CC: OR = 1.74, 95% CI = 1.23-2.47, P < .001) of the CCL5 - 28C/G polymorphism were also associated with an increased risk of AD. However, this significant association was not found in other alleles and genotypes (P > .05).

CONCLUSION

Our results show that the A allele, AG and AA + AG genotypes of the CCL5 - 403G/A polymorphism, the G allele and GG + GC genotype of the CCL5 - 28C/G polymorphism are risk factors for AD. Future studies with large population are still needed to further explore those correlations.

Persistent Neutrophil Infiltration and Unique Ocular Surface Microbiome Typify Dupilumab-Associated Conjunctivitis in Patients with Atopic Dermatitis

Objective

To elucidate the pathogenesis of dupilumab (Dupixent®)-associated ocular surface disease (DAOSD).

Design

Prospective single-center cohort study.

Subjects

Twenty patients with moderate-to-severe atopic dermatitis (AD) who received dupilumab and 10 age- and sex-matched healthy controls were enrolled in the study.

Methods

The study cohort underwent a thorough slit-lamp and entire-body dermatologic examination. Conjunctival swabs and smears were collected at baseline, 4 and 16 weeks after treatment initiation, and during the conjunctivitis episode. To analyse the ocular surface microbiome, 16S ribosomal RNA sequencing was performed, smears were hematoxylin and eosin stained, and serum cytokines were measured by using a multiplex immunobead assay.

Main Outcome Measures

Composition of ocular surface microbiome and cellular component as well as serum cytokine levels.

Results

Six of the 20 patients with AD developed DAOSD after dupilumab initiation; these patients responded after a delay to treatment as quantified by Eczema Area and Severity Index and Investigator's Global Assessment score. Conjunctival smears showed massive neutrophilic infiltration and serum analysis revealed increased systemic levels of neutrophil-priming proinflammatory cytokines, in particular interleukin-1β and tumor necrosis factor α, in patients with DAOSD compared with those without it. The ocular surface microbiome of patients with DAOSD was characterized by a diverse and persistent microbial colonization, particularly by Acetobacter aceti. In contrast, microbial diversity decreased in patients with AD without DAOSD after the initiation of dupilumab treatment, especially the abundance of Staphylococcus aureus. In vitro experiments substantiated the potential role of the microbiome, showing increased growth of A. aceti and decreased growth of S. aureus in presence of dupilumab.

Conclusions

Persistent neutrophilic infiltration and a unique microbial landscape on the ocular surface associated with elevated levels of systemic proinflammatory cytokines typify DAOSD.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references.

Repressive Control of Keratinocyte Cytoplasmic Inflammatory Signaling

The overactivity of keratinocyte cytoplasmic signaling contributes to several cutaneous inflammatory and immune pathologies. An important emerging complement to proteins responsible for this overactivity is signal repression brought about by several proteins and protein complexes with the native role of limiting inflammation. The signaling repression by these proteins distinguishes them from transmembrane receptors, kinases, and inflammasomes, which drive inflammation. For these proteins, defects or deficiencies, whether naturally arising or in experimentally engineered skin inflammation models, have clearly linked them to maintaining keratinocytes in a non-activated state or returning cells to a post-inflamed state after a signaling event. Thus, together, these proteins help to resolve acute inflammatory responses or limit the development of chronic cutaneous inflammatory disease. We present here an integrated set of demonstrated or potentially inflammation-repressive proteins or protein complexes (linear ubiquitin chain assembly complex [LUBAC], cylindromatosis lysine 63 deubiquitinase [CYLD], tumor necrosis factor alpha-induced protein 3-interacting protein 1 [TNIP1], A20, and OTULIN) for a comprehensive view of cytoplasmic signaling highlighting protein players repressing inflammation as the needed counterpoints to signal activators and amplifiers. Ebb and flow of players on both sides of this inflammation equation would be of physiological advantage to allow acute response to damage or pathogens and yet guard against chronic inflammatory disease. Further investigation of the players responsible for repressing cytoplasmic signaling would be foundational to developing new chemical-entity pharmacologics to stabilize or enhance their function when clinical intervention is needed to restore balance.

The Anti-Atopic Dermatitis Effects of Mentha arvensis Essential Oil Are Involved in the Inhibition of the NLRP3 Inflammasome in DNCB-Challenged Atopic Dermatitis BALB/c Mice

The NLRP3 inflammasome is upregulated by various agents, such as nuclear factor-kappa B (NF-κB), lipopolysaccharide (LPS), and adenosine triphosphate (ATP). The NLRP3 inflammasome facilitations the maturation of interleukin (IL)-1β, a proinflammatory cytokine that is critically involved in the pathogenesis of atopic dermatitis (AD). Although the NLRP3 inflammasome clearly exacerbates AD symptoms such as erythema and pruritus, drugs for AD patients targeting the NLRP3 inflammasome are still lacking. Based on the previous findings that Mentha arvensis essential oil (MAEO) possesses strong anti-inflammatory and anti-AD properties through its inhibition of the ERK/NF-κB signaling pathway, we postulated that MAEO might be capable of modulating the NLRP3 inflammasome in AD. The aim of this research was to investigate whether MAEO affects the inhibition of NLRP3 inflammasome activation in murine bone marrow-derived macrophages (BMDMs) stimulated with LPS + ATP in vitro and in a murine model displaying AD-like symptoms induced by 2,4-dinitrochlorobenzene (DNCB) in vivo. We found that MAEO inhibited the expression of NLRP3 and caspase-1, leading to the suppression of NLRP3 inflammasome activation and IL-1β production in BMDMs stimulated with LPS + ATP. In addition, MAEO exhibited efficacy in ameliorating AD symptoms in a murine model induced by DNCB, as indicated by the reduction in dermatitis score, ear thickness, transepidermal water loss (TEWL), epidermal thickness, and immunoglobulin E (IgE) levels. Furthermore, MAEO attenuated the recruitment of NLRP3-expressing macrophages and NLRP3 inflammasome activation in murine dorsal skin lesions induced by DNCB. Overall, we provide evidence for the anti-AD effects of MAEO via inhibition of NLRP3 inflammasome activation.

Association of atopic dermatitis with an increased risk of systemic lupus erythematosus: A systematic review and meta-analysis

Context:

Previous studies on the association between atopic dermatitis (AD) and systemic lupus erythematosus (SLE) have yielded inconsistent results.

Aims:

To investigate the relationship between atopic dermatitis and systemic lupus erythematosus.

Settings and Design:

Systematic review and meta-analysis.

Materials and Methods:

A systematic review was conducted on EMBASE and MEDLINE databases from inception to March 2020 using a search strategy that consisted of terms related to AD and SLE. Eligible study must be either cohort or case-control study. For cohort studies, they must include patients with AD and comparators without AD, then follow them for incident SLE. For case-control studies, they must include cases with SLE and controls without SLE and examine their prior history of AD.

Statistical Analysis Used:

Meta-analysis of the studies was performed using a random-effect, generic inverse variance method to combine effect estimate and standard error. Funnel plot was used to assess publication bias.

Results:

A total of 21,486 articles were retrieved. After two rounds of review by three investigators, six case-control studies were qualified for the meta-analysis. The case-control study meta-analysis found a significantly increased odds of SLE among patients with AD with the pooled odds ratio of 1.46 (95% CI, 1.05–2.04).

Conclusions:

A significant association between AD and increased odds of SLE was observed by this systematic review and meta-analysis.

Characterisation of the serum cytokine profile in feline atopic skin syndrome

BACKGROUND

Feline atopic skin syndrome (FASS) is a pruritic and inflammatory skin disease commonly encountered in cats. Three previous reports evaluated cytokine immune activation in cats diagnosed with feline allergic dermatitis. However, no significant upregulations were observed in allergic cats compared to healthy controls.

HYPOTHESIS/OBJECTIVE

To evaluate differences in the serum cytokine profile of cats diagnosed with FASS compared to healthy cats, and correlate serum markers with the extent of FASS skin disease using clinical scoring systems.

ANIMALS

Thirteen client-owned FASS cats and 12 healthy control cats.

METHODS AND MATERIALS

Thirteen cytokine and chemokines from the serum of FASS cats and healthy controls were analysed using a commercially available feline-specific multiplex assay.

RESULTS

Patients with FASS had a significant increase in serum concentrations of interferon-gamma (IFN-γ), interleukin (IL)-2, IL-13 and IL-18. In addition, cytokine/chemokines involved in inflammation and chemotaxis [IL-8, C-C Motif Chemokine Ligand (CCL)5, CCL2 and CXCL12], as well as growth factors, stem cell factor and Fms-related tyrosine kinase 3 ligand (Flt3L), also were significantly elevated. A significant positive correlation (r = 0.64) between the serum levels of Flt3L and Scoring Feline Allergic Dermatitis (SCORFAD) score was observed.

CONCLUSIONS

These results demonstrate the activation of a broad array of immune secretory cytokines in the serum of cats with FASS, which are largely associated with a mixed Th1 and Th2 inflammatory response along with specific growth factors. Further larger-sample studies are needed to assess the modulation of serum biomarkers in FASS by pharmacological/therapeutic interventions.

Assessment of dermatological quality of life in patients with childhood atopic dermatitis and their families

Aim

Atopic dermatitis is a chronic, itchy, inflammatory skin disease that progresses with exacerbations. This study was planned to determine how atopic dermatitis affects the quality of life of patients and their families.

Material and Methods

One hundred twenty patients with atopic dermatitis, as diagnosed using the Hanifin Rajka diagnostic criteria, and their families were included in the study. The patients were divided into two groups as active and remission. Disease severity was classified as mild, moderate, and severe according to the SCORAD index. Total IgE, peripheral eosinophil counts, and allergy skin tests were performed. Literate patients completed the Childrens' Dermatology Life Quality Index by themselves. The Infants' Dermatology Life Quality Index was completed by their families. Also, the Family Dermatological Quality of Life Index was completed by one of the parents for each patient.

Results

Among the 120 patients who participated in the study, 76 (63.33%) were male and 44 (36.66%) were female. The mean age was 4.36±3.52 years. The quality of life survey scores were statistically significantly lower in the remission group compared with the active group (p<0.05). The quality of life questionnaire scores were higher in the group with a severe SCORAD index (p<0.05). There was no significant correlation between total IgE, peripheral eosinophil count, skin test results, and questionnaire scores (p>0.05). At least one allergen susceptibility was detected in 65% of the patients who underwent allergy skin tests.

Conclusion

Quality of life was affected negatively in patients with atopic dermatitis and their families. In this study, the quality of life survey results were found to be higher in the active group and the group with a high SCORAD index compared with the remission group and the group with a low SCORAD index. Based on this finding, we can conclude that quality of life is negatively affected by high disease activity.

Keratinocyte-specific deletion of SHARPIN induces atopic dermatitis-like inflammation in mice

Spontaneous mutations in the SHANK-associated RH domain interacting protein (Sharpin) resulted in a severe autoinflammatory type of chronic proliferative dermatitis, inflammation in other organs, and lymphoid organ defects. To determine whether cell-type restricted loss of Sharpin causes similar lesions, a conditional null mutant was created. Ubiquitously expressing cre-recombinase recapitulated the phenotype seen in spontaneous mutant mice. Limiting expression to keratinocytes (using a Krt14-cre) induced a chronic eosinophilic dermatitis, but no inflammation in other organs or lymphoid organ defects. The dermatitis was associated with a markedly increased concentration of serum IgE and IL18. Crosses with S100a4-cre resulted in milder skin lesions and moderate to severe arthritis. This conditional null mutant will enable more detailed studies on the role of SHARPIN in regulating NFkB and inflammation, while the Krt14-Sharpin-/- provides a new model to study atopic dermatitis.

Evaluation of Peripheral Blood Eosinophilia in Adolescent and Adult Patients Suffering from Atopic Dermatitis and the Relation to the Occurrence of Allergy to Aeroallergens

Background:

Eosinophils play an important pathogenic role in atopic dermatitis (AD), but its exact function remains to be determined.

Aims and Objectives:

The aim of this study was to correlate the eosinophil count with the manifestations such as asthma bronchiale, rhinitis, level of total IgE, sensitization to mites, animal dander, bird feather, dust, mixture of grass, mixture of trees, mixture of fungi, duration of lesions (persistent or occasional during last year), family history about atopy, and onset of AD (under or above 5 year of age).

Materials and Methods:

Two hundred and seventy-two patients suffering from AD at the age of 14 year or older were examined – 100 men and 172 women with the average age of 26.7±9.5 years and with the average SCORAD index of 32.9±14.1. Complete dermatological and allergological examinations were performed in all patients with the evaluation of monitored manifestations. Mann–Whitney test for difference in medians was used for statistical evaluation.

Results:

The count of eosinophils in peripheral blood was significantly higher in patients with total IgE ≥200 IU/ml, with sensitization to dust, with persistent eczematous lesions and in patients with the onset of AD under 5 year of age. The count of eosinophils above 5% was recorded as well in patients suffering from asthma bronchiale, rhinitis, sensitization to mites, and in patients with positive family history about atopy, but the difference was not significant. On the other hand, the count of eosinophils was under 5% in patients with sensitization to animal dander, bird feather, mixture of grass and trees.

Conclusion:

Our results demonstrated the difference in the count of eosinophils in peripheral blood according to different manifestations in patients suffering from AD.

Clinical Signs, Staphylococcus and Atopic Eczema-Related Seromarkers

Childhood eczema or atopic dermatitis (AD) is a distressing disease associated with pruritus, sleep disturbance, impaired quality of life and Staphylococcus aureus isolation. The pathophysiology of AD is complex and various seromarkers of immunity are involved. We investigated if anti-staphylococcal enterotoxin IgE (anti-SE), selected seromarkers of T regulatory (Treg), T helper (Th) and antigen-presenting cells (APC) are associated with clinical signs of disease severity and quality of life. Disease severity was assessed with the Scoring Atopic Dermatitis (SCORAD) index, and quality of life with the Children's Dermatology Life Quality Index (CDLQI) in AD patients ≤18 years old. Concentrations of anti-staphylococcus enterotoxin A and B immunoglobulin E (anti-SEA and anti-SEB), selected Treg/Th/APC chemokines, skin hydration and transepidermal water loss (TEWL) were measured in these patients. Forty patients with AD [median (interquartile range) age of 13.1 (7.9) years) were recruited. Backward stepwise linear regression (controlling for age, personal allergic rhinitis and asthma, and other blood markers) showed the serum anti-SEB level was positively associated with S. aureus and S. epidermidis isolations, objective SCORAD, clinical signs and CDLQI. TNF-α (a Th1 cytokine) was positively associated with objective SCORAD (B = 4.935, p = 0.010), TGF-β (a Treg cytokine) negatively with disease extent (B = -0.015, p = 0.001), IL-18 (an APC cytokine) positively with disease extent (B = 0.438, p = 0.001) and with TEWL (B = 0.040, p = 0.010), and IL-23 (an APC cytokine) negatively with disease extent (B = -2.812, p = 0.006) and positively with pruritus (B = 0.387, p = 0.007).

CONCLUSIONS

Blood levels of anti-SEB, Th1, Treg and APC cytokines are correlated with various clinical signs of AD. AD is a systemic immunologic disease involving Staphylococcus aureus, cellular, humoral, cytokine and chemokine pathophysiology.

Epidermal Dysfunction Leads to an Age-Associated Increase in Levels of Serum Inflammatory Cytokines

Even though elderly populations lack visible or other clinical signs of inflammation, their serum cytokine and C-reactive protein levels typically are elevated. However, the origin of age-associated systemic inflammation is unknown. Our previous studies showed that abnormalities in epidermal function provoke cutaneous inflammation, and because intrinsically aged skin displays compromised permeability barrier homeostasis and reduced stratum corneum hydration, we hypothesized here that epidermal dysfunction could contribute to the elevations in serum cytokines in the elderly. Our results show first that acute disruption of the epidermal permeability barrier in young mice leads not only to a rapid increase in cutaneous cytokine mRNA expression but also an increase in serum cytokine levels. Second, cytokine levels in both the skin and serum increase in otherwise normal, aged mice (>12 months). Third, expression of tumor necrosis factor-α and amyloid A mRNA levels increased in the epidermis, but not in the liver, in parallel with a significant elevation in serum levels of cytokines. Fourth, disruption of the permeability barrier induced similar elevations in epidermal and serum cytokine levels in normal and athymic mice, suggesting that T cells play a negligible role in the elevations in cutaneous and serum inflammatory cytokines induced by epidermal dysfunction. Fifth, correction of epidermal function significantly reduced cytokine levels not only in the skin but also in the serum of aged mice. Together, these results indicate that the sustained abnormalities in epidermal function in chronologically aged skin contribute to the elevated serum levels of inflammatory cytokines, potentially predisposing the elderly to the subsequent development or exacerbation of chronic inflammatory disorders.

Cytokine production by PBMC and serum from allergic and non-allergic subjects following in vitro histamine stimulation to test fexofenadine and osthole anti-allergic properties

FXF is a third-generation antihistamine drug and osthole is assumed a natural antihistamine alternative. This paper compares peripheral blood mononuclear cell (PBMC) incubation with FXF and osthole, by studying FXF, osthole and histamine cytokine secretion in PBMC in vitro cultures. Mabtech kits determined the interleukins IL-1β, IL-4, IL-10, IL-13 and TNF-α. The influence of the above active substances on cytokine secretion in PBMC's and serum was assessed: cytokines were IL-1β, IL-4, IL-10, IL-13 and TNF-α; and cytokine levels secreted by untreated PBMCs in pure culture medium formed the absolute control (ctrl). We determined that osthole affects PBMC cytokine secretion to almost precisely the same extent as FXF (IL-1β, IL-4, IL-10 and TNF). In addition osthole had greater IL-13 blocking ability than FXF. Moreover, we observed significantly decreased IL-4 level in histamine/osthole theatment compared to histamine alone. Meanwhile, FXF not significantly decrease the level of IL-4 increased by histamine. This data indicates osthole's strong role in allergic inflamation. All results confirm our hypothesis that osthole is a natural histamine antagonist and therefore can be beneficially used in antihistamine treatment of conditions such as allergies.

Selected immunological parameters in clinical evaluation of patients with atopic dermatitis

Introduction

It has been suggested that soluble immune receptors (SIRs) such as sCD25 and sCD30 may serve as potential biomarkers in evaluation of atopic dermatitis (AD). Previous studies clearly indicated that serum levels of interleukin (IL)-13 and total IgE (tIgE) might be potentially useful in the evaluation of patents with AD.

Aim

To evaluate whether serum levels of sCD25 and sCD30 are suitable biomarkers of AD. Moreover, we have decided to estimate the usefulness of tIgE and IL-13 serum level determination in the evaluated population.

Material and methods

A group of 102 AD patients was investigated. Serum concentrations of sCD30, sCD25, IL-13 and tIgE were measured. The clinical phenotype of AD was classified as extrinsic (ADe) or intrinsic (ADi) based on the presence of IgE. Statistical analysis was performed to estimate correlations between obtained results and clinical features of the population such as AD phenotype, age, disease extent and severity.

Results

Extrinsic AD was diagnosed in 71% of patients, while ADi phenotype was observed in 29% of the investigated population. A negative correlation between serum levels of sCD25 and sCD30 and disease severity as well patients’ age was established. Serum levels of IL-13 did not reach the cut-off point set by the manufacturer. A positive correlation between serum levels of total IgE and disease severity and patients’ age was observed.

Conclusions

This paper shows that serum levels of sCD25 and sCD30 as well as tIgE are age dependent. Determination of serum levels of sCD25, sCD30 and IL-13 is not useful in everyday practice.

Altered Expression of IFN-λ2 in Allergic Airway Disorders and Identification of Its Cell Origins

This study investigated the expression levels of interferon- (IFN-) λ2 in peripheral blood and tissues. The results showed that the levels of IFN-λ2 were elevated by 17.9% and 14.2% in the plasma of allergic rhinitis (AR) and combined rhinitis with asthma (AR + AS), which was positively correlated with the level of tryptase but negatively correlated with the level of IL-10. IFN-λ2 was predominately expressed in the CD16+ cells and CD14+ cells in healthy control subjects (HC) but upregulated only in CD8+ cells of AR and in eosinophils of asthma. It was observed that approximately 6.6% and 7.0% dispersed tonsil cells and 5.8% and 0.44% dispersed lung cells are IFN-λ2+ mast cells and macrophages. Moreover, tryptase and agonist peptides of PAR-2 induced enhanced IFN-λ2 mRNA expression in A549 cells. In conclusion, the elevated levels of IFN-λ2 in the plasma of AR and AR + AS indicate that IFN-λ2 is likely to contribute to the pathogenesis of allergic airway disorders. The potential origins of the elevated plasma IFN-λ2 include mast cells, macrophages, and epithelial cells in tissues, neutrophils, monocytes, CD8+ T cells, and eosinophils in peripheral blood. Development of IFN-λ2 related therapy may help to treat or prevent allergic airway disorders.

Immunoglobulin e, interleukin-18 and interleukin-12 in patients with atopic dermatitis: correlation with disease activity

INTRODUCTION

Atopic dermatitis (AD) is a chronic inflammatory skin disorder. Immunological/inflammatory reactions are reported to play a role in AD but their role in disease activity has not been fully investigated. This study was done to investigate the role of immunoglobulin E (IgE), interleukin (IL)-18 and IL-12 in AD patients with different disease severities.

MATERIALS AND METHODS

Sera from 50 AD infants with varying levels of disease activity according to the scoring index of atopic dermatitis (SCORAD) index and 30 age-matched healthy controls were evaluated for serum levels of IgE, IL-18 and IL-12/p40.

RESULTS

Serum analysis showed higher levels of IgE, IL-18 or IL-12/p40 in AD patients compared with controls. Interestingly, not only was there an increased number of subjects positive for IgE, IL-18 or IL-12/p40, but also the levels of these parameters were higher among AD patients whose SCORAD scores were higher. In addition, a significant correlation was observed between the levels of these parameters and SCORAD scores.

CONCLUSION

These findings support an association between IgE, IL-18 or IL-12/p40 and AD. The stronger response observed in serum samples from patients with higher SCORAD scores suggest that IgE, IL-18 and IL-12/p40 may be useful in evaluating the progression of AD and in elucidating the mechanisms of disease pathogenesis.

The Drinking Effect of Hydrogen Water on Atopic Dermatitis Induced by Dermatophagoides farinae Allergen in NC/Nga Mice

Hydrogen water (HW) produced by electrolysis of water has characteristics of extremely low oxidation-reduction potential (ORP) value and high dissolved hydrogen (DH). It has been proved to have various beneficial effects including antioxidant and anti-inflammatory effects; however, HW effect on atopic dermatitis (AD), an inflammatory skin disorder, is poorly documented. In the present study, we examined the immunological effect of drinking HW on Dermatophagoides farinae-induced AD-like skin in NC/Nga mice. Mice were administered with HW and purified water (PW) for 25 days. We evaluated the serum concentration of pro-inflammatory (TNF-α), Th1 (IFN-γ, IL-2, and IL-12p70), Th2 (IL-4, IL-5, and IL-10), and cytokine expressed by both subsets (GM-CSF) to assess their possible relationship to the severity of AD. The serum levels of cytokines such as IL-10, TNF-α, IL-12p70, and GM-CSF of mice administered with HW was significantly reduced as compared to PW group. The results suggest that HW affects allergic contact dermatitis through modulation of Th1 and Th2 responses in NC/Nga mice. This is the first note on the drinking effect of HW on AD, clinically implying a promising potential remedy for treatment of AD.

Role of the Transcriptional Repressor BCL6 in Allergic Response and Inflammation

Various molecules participate in different phases of allergic reactions. This means that many genes are encoding molecules related to allergic reactions, such as cytokines, chemokines, and their receptors as effect or molecules. The transcriptional repressor BCL6 has emerged as a multifunctional regulator of lymphocyte differentiation and immune responses. BCL6-deficient (BCL6) mice display T helper type 2 (Th2)-type inflammation, which is caused by abnormality of both lymphoid cells and nonlymphoid cells. Thus, BCL6 apparently contributes to negative regulation of various central molecules such as cytokines, in particular Th2 cytokines, CC chemokines, and immunoglobulin E in allergic diseases. Therefore, BCL6 may be a molecular target for Th2-type allergic diseases.

T-regulatory cells in severe atopic dermatitis: alterations related to cytokines and other lymphocyte subpopulations

The changes in lymphocyte subpopulations in atopic dermatitis (AD) concern also T-regulatory cells. We investigated the expression of various surface receptors on CD3⁺CD4⁺CD25^highFoxP3⁺ T-regulatory cells and the activation CD28⁺ receptor and the inhibitory CD152⁺ receptor on helper/inducer as well as cytotoxic/suppressor T cells. Peripheral blood lymphocytes of 15 AD patients and 20 healthy subjects were analyzed by flow cytometry using monoclonal antibodies. The concentrations of IL-6, IL-10 and TGF-β were determined in the serum and the supernatant of ConA-stimulated CD4⁺ lymphocytes. In AD patients the percentage of CD4⁺CD25^highFoxP3⁺ as well as CD3⁺CD8⁺ cells increased, which positively correlated with SCORAD index (r = 0.55, p = 0.03). The concentrations of IL-10 in the CD4⁺ lymphocyte culture supernatants and the concentrations of TGF-β in the sera and the supernatant negatively correlated with the severity of AD (p < 0.01, r = −0.63; p < 0.02, r = −0.64 and p < 0.03, r = −0.58, respectively), whereas the serum concentration of IL-6 correlated positively (p < 0.003, r = 0.71). The regulatory cells expressed more CD62L and CD134 surface markers but less CD95. Reduced expression of the apoptotic CD95 receptor suggests that survival time of these cells is prolonged. Since CD62L and CD134 were upregulated, the enhanced modulatory effect of CD4⁺CD25^highFoxP3⁺ cells seemed to be suggested, which may result in increased co-expression of CD28/CD152 on both CD4⁺ and CD8⁺ subpopulations.

How aluminum adjuvants could promote and enhance non-target IgE synthesis in a genetically-vulnerable sub-population

Aluminum-containing adjuvants increase the effectiveness of vaccination, but their ability to augment immune responsiveness also carries the risk of eliciting non-target responses, especially in genetically susceptible individuals. This study reviews the relevant actions of aluminum adjuvants and sources of genetic risk that can combine to adversely affect a vulnerable sub-population. Aluminum adjuvants promote oxidative stress and increase inflammasome activity, leading to the release of IL-1β, IL-18, and IL-33, but not the important regulatory cytokine IL-12. In addition, they stimulate macrophages to produce PGE₂, which also has a role in regulating immune responses. This aluminum-induced cytokine context leads to a T(H)2 immune response, characterized by the further release of IL-3, IL-4, IL-5, IL-9, IL-13, and IgE-potentiating factors such as sCD23. Genetic variants in cytokine genes, such as IL-4, IL-13, IL-33, and IL-18 influence the response to vaccines in children and are also associated with atopy. These genetic factors may therefore define a genetically-vulnerable sub-population, children with a family history of atopy, who may experience an exaggerated T(H)2 immune response to aluminum-containing vaccines. IL-4, sCD23, and IgE are common factors for both atopy and the immune-stimulating properties of aluminum adjuvants. IL-4 is critical in the production of IgE and total IgE up-regulation. IL-4 has also been reported to induce the production of sCD23 and trigger resting sIgM+, sIgD+ B-cells to switch to sIgE+ B-cells, making them targets for IgE-potentiating factors. Further, the actions of IgE-potentiating factors on sIgE+ B-cells are polyclonal and unrestricted, triggering their differentiation into IgE-forming plasma cells. These actions provide a mechanism for aluminum-adjuvant promotion and enhancement of non-target IgE in a genetically vulnerable sub-population. Identification of these individuals may decrease the risk of adverse events associated with the use of aluminum-containing vaccines.

Interleukin-18 Gene Polymorphisms in Egyptian Patients with Allergic Diseases

Background

Allergic diseases, such as allergic rhinitis (AR) and atopic dermatitis (AD), affect a large proportion of people worldwide. Both have environmental and genetic predisposing factors. Single nucleotide polymorphisms (SNPs) in interleukin (IL)-18, may play a direct role in the disease pathogenesis. This study was designed to investigate the association of the IL-18 gene SNPs (-137 G/C [rs187238], and −140 C/G [rs360721]) with AR and AD, as well as their relations to the diseases’ severity.

Methods

Seventy-five individuals were enrolled in the study including, 25 AD children, 25 AR patients, and 25 unrelated healthy adult volunteers who served as controls. Genotyping was performed by polymerase chain reaction and restriction fragment length polymorphism analysis.

Results

AR and AD patients showed no significant differences in the genotype distribution and allele frequencies of −137 G/C and −140 C/G SNPs when compared independently with the control group. However, the −140 GG genotype and the −140 G allele were more often associated with severe AD compared with mild and moderate phenotypes (p = 0.01 and 0.001, respectively; odds ratios [ORs], 14.25 [95% CI, 1.48–143.2] and 16 [95% CI, 2.8–90.46], respectively). Moreover, the −137 G allele was associated with moderate/severe AR (p = 0.019; OR, 6.1 [95% CI, 1.34–28.1]).

Conclusion

This preliminary study indicates that the studied polymorphisms do not confer susceptibility to allergy in Egyptian patients but may be related to the disease phenotype. However, the role of IL-18 in allergy may be too complex to be reflected in a simple association study.

Bronchial hyperresponsiveness in seasonal allergic rhinitis patients is associated with increased IL-18 during natural pollen exposure

BACKGROUND

The mechanism of bronchial hyperresponsiveness (BHR) is not certain in seasonal allergic rhinitis (SAR) patients.

OBJECTIVE

We aimed to investigate the effects of natural pollen exposure on IL-18 and its relationship with BHR.

METHODS

Thirty-two SAR patients with grass pollen sensitivity, 14 nonallergic rhinitis (NAR) patients and 17 normal-controls were included. Sixteen SAR patients had BHR during pollen season and off-season. Serum IL-18 levels were measured in SAR patients during pollen season between May-August and off-season between November-February. IL-18 levels were measured in NAR patients and normal controls once.

RESULTS

During pollen season, SAR patients with BHR had significantly increased levels of IL-18 than those without BHR (279.2 ± 161.1 versus 145.3 ± 101.0 pg/ml, p=0.012). Serum IL-18 levels were not different between SAR patients with and without BHR during off-season (233.8 ± 139.7 versus 183.2 ± 162.9 pg/ml, p=0.16). Serum IL-18 levels in SAR patients during pollen season (212.3 ± 148.8 pg/ml) and off-season (208.5 ± 151.5 pg/ml) were not different than those NAR patients (224.8 ± 180.1 pg/ml, p=0.98 and p=1.0, respectively) and normal controls (174.8 ± 76.0 pg/ml, p=0.60 and p=0.76, respectively).

CONCLUSION

The results suggested us that BHR in SAR patients is associated with increased IL-18 during natural pollen exposure.

A functional promoter polymorphism of the human IL18 gene is associated with aspirin-induced urticaria

BACKGROUND

Urticaria is the commonest cutaneous reaction caused by aspirin or other nonsteroidal anti-inflammatory drugs. The pathogenesis of aspirin-induced urticaria (AIU) is not fully understood, but appears to involve mast cell activation and neutrophil infiltration.

OBJECTIVES

To investigate the genetic contribution of interleukin (IL)-18, which can amplify acute inflammation by promoting mast cell activation, neutrophil migration and cytokine production, to the pathogenesis of AIU.

METHODS

A case-control association study was performed using 275 patients with AIU and 196 normal healthy controls in a Korean population. Two promoter polymorphisms of the IL18 gene (-607A/C and -137G/C) were genotyped using the primer extension method. The functional effect of the IL18 gene promoter polymorphism was investigated through in vitro studies including a luciferase reporter assay and electrophoretic mobility shift assays (EMSAs) and ex vivo studies involving neutrophil chemotaxis assays.

RESULTS

A significant association was detected between both AIU in general and the aspirin-intolerant acute urticaria (AIAU) phenotype and the IL18 promoter polymorphism -607A/C. Patients with AIAU showed higher frequencies of the C(-607) G(-137) haplotype, ht1 [CG], compared with controls (P=0·02). Moreover, ht1 [CG] showed a high transcript haplotype by the luciferase activity assay, and EMSAs identified a -607C allele-specific DNA-binding protein as CREB2. Neutrophil chemotactic activity was highest in subjects with AIU exhibiting the high transcript haplotype, ht1 [CG] (P=0·019).

CONCLUSIONS

The high transcript haplotype ht1 [CG] of the IL18 gene may contribute to the development of acute cutaneous inflammation sensitive to aspirin, leading to the clinical presentation of AIAU.

Suppression of inflammation by recombinant Salmonella typhimurium harboring CCL22 microRNA

Atopic dermatitis (AD) is an inflammatory, chronically relapsing, puritic skin disorder. These syndromes result from multifactorial inheritance, with interaction between genetic and environmental factors. In particular, the macrophage-derived chemokine CCL22 is directly implicated in skin inflammatory reactions and its levels are significantly elevated in serum and correlated with disease severity in AD. We tested the suppression of the CCL22 gene by microRNA (miRNA) and observed the effects in mice with inflammation similar to AD. We used Salmonella as a vector to deliver miRNA. The recombinant strain of Salmonella typhimurium expressing CCL22 miRNA (ST-miRCCL22) was prepared for in vivo knockdown of CCL22. ST-miRCCL22 was orally inoculated into mice and the CCL22 gene suppressed with CCL22 miRNA in the activated lymphocytes. IgE and interleukin-4 were inhibited and interferon-γ was induced after treatments with ST-miRCCL22 and CCL22 was suppressed. Further, Th17 cells were suppressed in the atopic mice treated with ST-miRCCL22. These results suggested that suppression of the CCL22 gene using Salmonella induced anti-inflammatory effects.

Therapeutic effects of recombinant Salmonella typhimurium harboring CCL22 miRNA on atopic dermatitis-like skin in mice

Th-2-biased immune responses are known to play a key role in the pathogenesis of atopic dermatitis. In particular, the macrophage-derived chemokine CCL22 is directly implicated in Th-2-associated skin inflammatory reactions, and its levels are significantly elevated in serum and are correlated with disease severity in atopic dermatitis. In this study, we tested the development of genetic therapeutic options to treat atopic dermatitis using bacteria expressing miRNA. We constructed a recombinant strain of Salmonella typhimurium expressing CCL22 miRNA (ST-miRCCL22) for the in vivo knockdown of CCL22. The CCL22 gene was downregulated with CCL22 miRNA in activated lymphocytes. In mice with a cutaneous disease similar to atopic dermatitis, interleukin-4 was inhibited and interferon-g was induced after treatments with ST-miRCCL22. Furthermore, CCL22 levels were suppressed in the atopic mice treated with ST-miRCCL22. These results suggest that ST-miRCCL22 may be an effective genetic agent for treating atopic dermatitis.

Relationship between serum levels of interleukin-18, IgE and disease severity in patients with atopic dermatitis

BACKGROUND

Interleukin (IL)-18 is a pleiotropic cytokine. Synergistically with IL-12, IL-18 promotes immune responses of the T helper type, by enhancing synthesis of interferon-γ and inhibiting IgE production. IL-18 can also enhance production of IL-4 and IL-13 production, and stimulate synthesis of IgE. Moreover, in the presence of IL-3, IL-18 can directly stimulate basophils and mast cells to produce their mediators in an IgE-independent manner. These results indicate a role for IL-18 in the pathogenesis of atopic dermatitis (AD).

AIM

To examine the association of serum IL-18 with IgE levels and disease severity in patients with AD.

METHODS

ELISA was used to measure IL-18 and total IgE levels in the sera of 67 patients with AD and 50 healthy volunteers. The SCORing Atopic Dermatitis (SCORAD) tool was used to determine the severity of this disease.

RESULTS

The mean serum level of IL-18 in study group (155.68 pg/mL) was significantly higher than that of controls. IL-18 was also significantly higher in the sera of the patients with severe AD than in those with milder disease. There was a correlation with IgE and IL-18 levels, as patients who had high IgE levels also had high IL-18 levels, compared with controls.

CONCLUSION

IL-18 seems to play an important role in the pathogenesis of AD, but this requires further study. IL-18 could be a useful clinical marker of disease severity in AD.

Investigation of cytokine levels and their association with SCORAD index in adults with acute atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease with increasing frequency over the last decades, especially in adults. Cytokines orchestrate atopic skin inflammation. Objectives  The aim of this study was to compare serum levels of cytokines in adult patients with acute AD (AD1) with other groups of AD patients and controls and investigate the possible association between such cytokines and disease severity.

METHODS

We measured cytokine levels using flow cytometry in 21 adult patients with acute AD, 12 adults with chronic AD, 10 children with acute AD and 10 healthy adults.

RESULTS

Flow cytometry analysis of cytokines revealed that interleukin 10 (IL-10), IL-6, interferon γ (IFN-γ) and IL-4 levels were significantly decreased in AD1 group compared with controls, whereas IL-2 and tumour necrosis factor (TNF) did not differ. Comparison of AD1 group with adults chronic phase group showed that IgE, eosinophil and IL-2 levels remained unaltered, whereas IL-10, IL-6, IFN-γ, IL-4 and TNF were significantly decreased. SCORAD and IgE levels were significantly increased, IL-10, IL-6 and IFN-γ were decreased and TNF, IL-2, IL-4 and eosinophil levels remained unchanged in AD1 group compared with children acute phase group. Within AD1 group correlation analysis revealed that IgE and TNF levels were significantly associated with AD severity. Coefficient of determination analysis revealed that TNF and IgE levels could explain 49.14% and 35.28% of the variance of SCORAD.

CONCLUSIONS

These data indicate that serum IgE and TNF levels correlate with AD severity and that serum cytokines are downregulated in AD1 group. Further studies are clearly needed to elucidate cytokines' role in adults with AD.

Autologous serum skin test response in chronic spontaneous urticaria and respiratory diseases and its relationship with serum interleukin-18 level

Autologous serum skin test (ASST) is mostly used in chronic spontaneous urticaria (CSU) to show autoreactivity. Interleukin-18 (IL-18) has also been shown to be involved in autoimmune conditions. To investigate the role of autoreactivity assessed by ASST in CSU and respiratory diseases and to investigate whether this autoreactive state is related to IL-18 level or other clinical covariates. Fifty-five patients with CSU (mean age: 40.3 ± 12.3 years), 70 patients with persistent asthma (mean age: 43.7 ± 9.6 years), 21 patients with seasonal allergic rhinitis (SAR) (mean age: 35.5 ± 11.8 years) and 20 normal controls (mean age: 37.7 ± 9.8) were included. All subjects underwent a laboratory examination and skin prick test. ASST was performed and serum IL-18 levels were measured in all subjects. Positive response to ASST and serum IL-18 levels were higher in CSU patients than those with respiratory diseases (asthma and SAR) (P = 0.034 and 0.002, respectively) and normal controls (P = 0.004 and 0.031, respectively). Considering all patients, IL-18 levels were higher in patients with positive ASST (301.8 ± 194.4 vs. 241.8 ± 206.3 pg/ml, P = 0.036) than ASST negative patients. ASST response was associated with disease severity in CSU (P = 0.037) and asthma patients (P = 0.001). Multivariate analysis showed that positive response to ASST was significantly associated with diagnosis of CSU (OR: 3.13, 95% CI: 1.25-7.87) and female gender (OR: 3.98, 95% CI: 1.19-13.38). ASST response could be related with activity of the disease. A positive ASST response found in respiratory diseases patients suggests that it may occur as a result of some inflammatory events during the diseases' process.

A functional polymorphism in IL-18 is associated with severity of bronchial asthma

RATIONALE

IL-18 is a unique cytokine that enhances innate immunity and both Th1- and Th2-driven immune responses. Recent murine and human genetic studies have shown its role in the pathogenesis of asthma.

OBJECTIVES

We conducted an association study in a Japanese population to discover variants of IL-18 that might have an effect on asthma susceptibility and/or progression and conducted functional analyses of the related variants.

METHODS

The IL-18 gene locus was resequenced in 48 human chromosomes. Asthma severity was determined according to the 2002 Global Initiative for Asthma Guidelines. Association and haplotype analyses were performed using 1,172 subjects.

MEASUREMENTS AND MAIN RESULTS

Although no polymorphisms differed significantly in frequency between the control and adult asthma groups, rs5744247 C>G was significantly associated with the severity of adult asthma (steps 1, 2 vs. steps 3, 4; P = 0.0034). We also found a positive association with a haplotype (P = 0.0026). By in vitro functional analyses, the rs5744247 variant was found to increase enhancer-reporter activity of the IL-18 gene in bronchial epithelial cells. Expression levels of IL-18 in response to LPS stimulation in monocytes were significantly greater in subjects homozygous for the susceptibility G allele at rs5744247 C>G. Furthermore, we found a significant correlation between the serum IL-18 level and the genotype of rs5744247 (P = 0.031).

CONCLUSIONS

Although the association results need to be replicated by other studies, IL-18 variants are significantly associated with asthma severity, and the rs5744247 variant reflects higher transcriptional activity and higher expression of IL-18 in LPS-stimulated monocytes and a higher serum IL-18 level.

Soluble immune receptor serum levels are associated with age, but not with clinical phenotype or disease severity in childhood atopic dermatitis

BACKGROUND

Soluble immune receptors (SIRs) have been proposed as biomarkers in patients with atopic dermatitis (AD). However, their clinical applicability in affected children has rarely been studied.

OBJECTIVE

To assess the diagnostic usefulness of serum SIRs in childhood AD by correlating the obtained receptor profiles with serological parameters and clinical features such as age, AD phenotype and disease severity.

METHODS

We investigated 100 children with AD. The sCD14, sCD23, sCD25, sCD30, total IgE (tIgE) and eosinophilic cationic protein (ECP) were determined using sera of all children. The clinical phenotype was classified as extrinsic AD (ADe) or intrinsic AD (ADi) by the presence of allergen-specific IgE antibodies.

RESULTS

A total of 55 male and 45 female children were recruited. The sCD23, sCD25 and sCD30 serum levels revealed significant age-dependency. At a mean SCORAD of 40 (range 8-98), none of the evaluated SIRs was correlated to disease severity. In all, 73% of patients suffered from ADe while 27% showed the ADi phenotype. None of the analysed SIRs differed significantly between ADe and ADi patients, while tIgE and ECP levels were elevated in the ADe subgroup.

CONCLUSION

The current study provides evidence that sCD23, sCD25 and sCD30 serum levels are highly age-dependent. Serum concentrations of all investigated SIRs did not significantly correlate with disease severity in children with AD and were not differentially expressed in patients of different AD phenotypes. Therefore, we believe that the studied SIRs cannot be regarded as clinically useful biomarkers for the assessment of childhood AD.

Expression, purification and structural analysis of human IL-18 binding protein: a potent therapeutic molecule for allergy

BACKGROUND

While interleukin-18 (IL-18) plays an important role in the innate and adaptive immune responses, it can also cause severe allergic inflammatory reactions. Thus it is a molecule currently being targeted for therapy. The natural intrinsic inhibitor of IL-18 receptor activation, IL-18 binding protein (IL-18BP), shows a great potential for the treatment of allergy.

METHODS

Expression and purification of recombinant human IL-18BP (rhIL-18BP) were performed using the baculovirus system to develop a therapeutic molecule for the treatment of IL-18-related diseases and to investigate the structural basis of its inhibitory mechanism.

RESULTS

Purified rhIL-18BP potently inhibited the production of interferon-gamma by peripheral blood mononuclear cells in the presence of lipopolysaccharide and by human myelomonocytic KG-1 cells in the presence of IL-18 (IC50 = 0.4 nM). Surface plasmon resonance showed a high affinity (Kd = 0.46 nM) for rhIL-18BP in binding hIL-18. Structural analysis indicated that the stoichiometry between IL-18 and IL-18BP is 1 : 1 in solution and the model structure of the complex suggests that the key residues on IL-18 (L5, K53, S55) and the estimated key residues on IL-18BP (F93,Y97, F104) could have interactions. The structural mechanism of IL-18BP inhibition might be a competition for Site 2 on rIL-18 so that IL-18BP can prevent IL-18 receptor alpha from binding to Site 2 and inhibit IL-18 receptor activation.

CONCLUSIONS

IL-18BP has unique features with respect to its structure, binding mode and inhibitory mechanism. It is a molecule that has a great potential for the therapy of allergy.

Effects of repeated respiratory syncytial virus infections on pulmonary dendritic cells in a murine model of allergic asthma

BACKGROUND

Primary and secondary respiratory syncytial virus (RSV) infection differentially regulates preexisting allergic airway inflammation.

OBJECTIVES

The present study was designed to determine the effects of primary and secondary low-grade RSV infections on pulmonary dendritic cell (DC) functions.

METHODS

Eight groups of BALB/c mice were used: one group each for control primary and secondary sensitization, primary and secondary sensitization to Dermatophagoides farinae (Derf) allergen, primary and secondary infection with RSV, and primary and secondary sensitization to Derf plus infection with RSV. CD11c+ pulmonary DCs were isolated from these mice and then transferred to naïve mice followed by intranasal Derf challenge. Furthermore, either anti-IL-12 monoclonal antibody (alphaIL-12 mAb) or anti-IL-10 (alphaIL-10) mAb were injected into donor mice after Derf challenge and during RSV infection to determine the involvement of IL-12 and IL-10.

RESULTS

Primary RSV infection failed to induce polarization in DCs since it failed to induce IL-10 and IL-12 production in Derf-sensitized donor lung. In contrast, secondary RSV infection significantly enhanced IL-12 production from Derf-sensitized donor lung, thereby enhancing both Th1 and Th2 responses. During RSV infection, alphaIL-12 but not alphaIL-10 mAb treatment blocked these immunological effects.

CONCLUSION

Via IL-12, DCs may play a critical role in shifting the immune response in this experimental model of repeated respiratory viral infection in allergic asthma.

Association of interleukin-18 gene polymorphism with asthma in Chinese patients

Like other allergic diseases, asthma results from multiple conditions. Asthmatic beginning and severity are mediated by both environmental and genetic factors. In asthma studies, important work is realization of the genetic background and identification of genetic factors resulting in asthma development and phenomena. Here, we investigated whether interleukin (IL)-18 single nucleotide polymorphisms (SNPs) are involved in Chinese asthma patients. IL-18 (IL-18) SNP was detected by polymerase chain reaction (PCR)-based restriction analysis in 201 patients with asthma and 60 normal controls. Significant differences were found in the genotype distribution of IL-18 SNP between asthma patients and controls (P=0.000003). Allelic frequency of the IL-18 gene distinguished asthma patients from controls (P=0.000066). The results revealed a significant difference between asthma patients and normal controls in IL-18 SNP and a statistical correlation between IL-18 polymorphisms (105A/C) and asthma formation. We concluded that Chinese who carry the C/C homozygote of the IL-18-105A/C gene polymorphism in coding regions may have a higher risk of developing asthma.

Staphylococcus aureus skin colonization in atopic dermatitis children is associated with decreased IFN-gamma production by peripheral blood CD4+ and CD8+ T cells

Atopic dermatitis (AD) is a chronic inflammatory skin disorder, which is associated with an increased expression of Th2 cytokines with concomitant decrease in IFN-gamma production by circulating CD4+ and CD8+ T cells. The skin of patients with AD is often colonized by Staphylococcus aureus, which may reflect in changes in immunological parameters. The aim of the study was flow cytometric measurement of some peripheral blood lymphocyte subsets expressing naive/memory marker (RA/RO) and activation marker (CD25) as well as intracellular production of IFN-gamma by peripheral blood CD4+ and CD8+ T cells from varied severity AD children and determine the impact of S. aureus skin colonization on cytokines profiles. There was a significant increase in the percentage of CD4+ and CD8+ T cells producing IL-4 and IL-13 and decrease in the percentage of CD4+ and CD8+ T cells producing IFN-gamma upon in vitro stimulation with phorbol 12-myristate 13-acetate and ionomycin in children with AD compared to healthy ones. The absolute number of CD4+ and CD8+ T cells expressing memory marker CD45RO was elevated as compared with controls. The severity of AD was positively correlated with the percentage of lymphocyte subsets: CD45RO+, CD4+CD45RO+, and the percentage of CD3+ and CD4+ expressing CD25 as well as the number of S. aureus on the skin. In conclusion, both CD4+ and CD8+ memory T cells are involved in the immunopathogenesis of AD. S. aureus skin colonization is related with disease severity and changes in expression of CD45RO and CD25 on T cells. A decrease in the percentage of CD4+ and CD8+ T cells producing IFN-gamma in AD children may explain propensity for skin infection.

Association of the single-nucleotide polymorphism and haplotype of the interleukin 18 gene with atopic dermatitis in Koreans

BACKGROUND

IL-18 is a proinflammatory cytokine that plays an important role for T-helper type 1 (Th1) and Th2 cytokine in the presence/absence of IL-12. It has been recently shown that human IL-18 plays a role in atopic dermatitis (AD) by enhancing IL-4 and IL-13 production and by stimulating the synthesis of IgE.

OBJECTIVE

We wanted to evaluate the associations of single-nucleotide polymorphism (SNP) and the haplotype in the IL-18 gene, hence we performed genotyping for the SNPs in the IL-18 gene in AD patients and normal controls.

METHOD

We genotyped three SNPs from the IL-18 gene for the 1120 case-control samples (646 AD patients and 474 normal controls). We measured the serum IL-18, IL-4 and IL-13 concentrations in 74 individuals (25 ADe, 25 ADi and 24 controls) by performing ELISA.

RESULT

The rs795467 SNP and haplotype T-T-C were significantly associated with AD, and especially between the ADe and normal control groups (P=0.03 and 0.01). The serum IL-18 concentration was higher in the AD group than in the normal controls without any correlation with the rs795467 polymorphism. We did not find any correlations between the serum IL-18 levels and the SCORing atopic dermatitis index, the blood eosinophil counts and the ECP, and there was no correlation between the serum IL-18 levels and the serum IL-4 and IL-13 levels.

CONCLUSION

We found that the one SNP and the haplotype T-T-C were strongly associated with the allergic type of AD, but not with the non-allergic intrinsic type. These data support the hypothesis that IL-18 up-regulates IgE production, yet more experiments will be needed to prove the in vivo involvement of Th2 cytokine.

Dietary Supplementation with Lactic Acid Bacteria Attenuates the Development of Atopic Dermatitis-Like Skin Lesions in NC/Nga Mice in a Strain-Dependent Manner

BACKGROUND

Dietary supplementation with lactic acid bacteria (LAB) is a potential approach to the prevention and manipulation of allergic diseases such as atopic dermatitis (AD). However, the influence of different bacterial strains and their immunomodulating capacities is still largely unknown.

METHODS

AD-like skin lesions were induced by sensitization to and repeated challenges with picrylchloride in the Th2-skewed NC/Nga mouse strain. The effects of LAB supplementation were assessed over time by monitoring clinical scores and plasma IgE levels. In some cases, mast cell infiltration, cutaneous hypersensitivity responses and cytokine mRNA expression in auricles were also examined. Additionally, cytokine production in vitro and cytokine mRNA accumulation in major lymphoid tissues were measured, comparing Lactobacillus paracasei KW3110 with L. rhamnosus GG (LGG).

RESULTS

Supplementation with KW3110 significantly reduced the development of AD-like skin lesions, accompanied by less mast cell infiltration and lower plasma IgE levels. KW3110 also suppressed immediate hypersensitivity reactions and IL-4 mRNA expression in the auricles. These preventive effects sustained when supplementation was terminated; moreover, inhibitory effects were also observed even when supplementation was initiated after the onset of symptoms. In accordance with its effects on IL-12 and IL-4 production in vitro, KW3110 prevented the emergence of clinical symptoms more effectively than LGG in vivo.

CONCLUSIONS

Supplementation with KW3110 significantly attenuated the onset and exacerbation of AD-like symptoms in NC/Nga mice. The effects were more prominent than those obtained with LGG, suggesting the importance of differences between LAB strains and their immunomodulating capacity.

Blood serum interferon-gamma bioactivity is low in weanling mice subjected to acute deficits of energy or both protein and energy

The main objective of the present study was to determine the influence of acute deficits of protein and energy on the blood serum level of interferon-gamma, a signature type 1 polarising inflammatory cytokine. In two 14 d experiments, male and female C57BL/6J mice, initial age 19 d, consumed a complete purified diet ad libitum or in restricted daily quantities, or had free access to an isoenergetic purified low-protein diet. A zero-time control group (age 19 d) was included in the second experiment. Serum interferon-gamma was assessed in both experiments by sandwich ELISA and, in the second experiment, also by a bioassay based on inhibition of proliferation by WEHI-279 B lymphoma cells. The immunoassay detected interferon-gamma inconsistently in all groups (range 0-14 pg/ml; detection limits 1 x 5 and 0 x 7 pg/ml in experiments 1 and 2, respectively). By contrast, interferon-gamma bioactivity was found in all animals of each group (means 339, 499, 124 and 200 pg/ml in zero-time controls, age-matched controls, low-protein and restricted intake groups, respectively; detection limit, 12 pg/ml), and the mean serum bioactivity of each malnourished group was low compared with the age-matched control (P <or=0 x 05). The present study defines the physiological serum interferon-gamma bioactivity of the adolescent mouse. Moreover, to the extent achievable by way of the blood, the results reflect the influence of metabolically diverse forms of acute malnutrition on the polarising type 1 cytokine profile within lymphoid microenvironments wherein immune responses arise. Therefore, the results suggest a mechanism underlying the cell-mediated inflammatory incompetence that characterises acute, prepubescent malnutrition.

Interleukin-18 gene polymorphism, but not interleukin-2 gene polymorphism, is associated with rheumatoid arthritis

To investigate whether polymorphisms of IL-2 and IL-18 genes are associated with rheumatoid arthritis (RA), polymorphisms of IL-2 and IL-18 genes were detected by polymerase-chain-reaction-based restriction analysis in the patients with RA and normal controls. The results for the IL-18 gene revealed a significant difference between the patients and the normal controls (p = 0.000003), but there was no significant difference for the IL-2 gene (p = 0.876). The IL-18 gene 105A allele was associated with RA in Chinese patients. Individuals possessing the 105A allele had a higher incidence of RA. A lack of association of IL-2 gene polymorphism between RA patients and healthy individuals was noted. The results of this study provide genetic evidence that IL-18-105A/C polymorphism may play an effective role in RA.