Decreased FOXP3 mRNA expression in children with atopic asthma and IgE-mediated food allergy

BACKGROUND

The role of T regulatory lymphocytes has been investigated in various allergic diseases. However, the precise relation between the phenotype and severity of allergic diseases and the changes in FOXP3 mRNA expression are not fully understood.

OBJECTIVE

To compare the expression of FOXP3 mRNA in children with asthma with and without concomitant food allergy (FA) with healthy children and children with only FA.

METHODS

The study included 82 children: 15 with atopic asthma and IgE-dependent FA, 27 with atopic asthma without FA, 20 with IgE-dependent FA without asthma, and 20 healthy children without atopy. Reverse transcription was performed using a commercially available High Capacity cDNA Archive Kit (Applied Biosystems, Carlsbad, California). Analysis was carried out with a 7900HT real-time polymerase chain reaction system (Applied Biosystems).

RESULTS

The average level of the FOXP3 gene expression in children with allergy was significantly lower compared with healthy children (2.2 ± 1.3 vs 4.2 ± 4.2; P = .014). The lowest mean level of FOXP3 mRNA expression (1.9 ± 1.6) was recorded in children with asthma and FA, and the highest level (4.2 ± 4.2) was recorded in healthy children without atopy (P = .036). A milder course of asthma or the degree of allergic reaction after a food challenge was associated with higher FOXP3 mRNA expression.

CONCLUSION

Significantly lower levels of FOXP3 gene expression, observed more commonly in children with asthma and IgE-dependent FA than in healthy controls, were associated with a more severe clinical course. Therefore, FOXP3 expression could serve as an indicator of severe asthma with concomitant atopic conditions such as IgE-dependent FA.

The effect of IL-2, IL-12 and IL15 on the function of natural killer cells in children suffering from type 1 diabetes mellitus

INTRODUCTION

The immunologic reaction of pancreatic islets destruction leads to the occurrence of type 1 diabetes mellitus (T1D). The autoreactive lymphocytes play the pivotal role in this process although mechanisms regulating the lymphocyte migration and infiltration of Langerhans islets have not been fully understood yet. The in vitro studies showed natural killer (NK) cells potency to initiate pancreatic islets cell lyses. Many authors postulate that NK cells may be involved in this reaction.

AIM OF THE STUDY

The aim of the study was to evaluate the effect of IL-2, IL-12 and IL-15 stimulation on peripheral blood NK cells in children suffering from type 1 diabetes mellitus in comparison to healthy controls.

MATERIAL AND METHODS

Fifteen children with type 1 diabetes and 10 healthy adults were examined. NK cells were isolated by the magnetic cell separation system (MACS). For activation, NK cells were cultured with IL-2, IL-12 and IL-15 for 24 hours. The production of IFN-γ and IL-10 by NK cells was measured using commercial ELISA kits. FACS analysis of cell surface antigens--CD16, CD56, NKG2D and CD137 was performed using LSR II flow cytometer.

RESULTS

In children with T1D the IFN-γ median concentration in supernatant obtained from NK cells culture was 16.831 ng/ml (inter quartile range 5.566-25.509) and did not statistically differ from median IFN-γ concentration in the control group--14.810 ng/ml (7.022-18.785), p = 0.76. In contrast, the IL-10 median concentration was statistically higher in T1D patients 7.87 pg/ml (1.32-11.37) than in healthy participants--1.41 pg/ml (1.05-4.81), p = 0.01. The median (inter-quartile range) percentage of NK NKG2D(+) was found in 0.42% (0.28-0.76) cells of TID patients versus 0.72% (0.53-1.08) in the controls (p = 0.05). There was no difference between -T1D group and the control group in regard to NK cells expressing CD137 - 6.58% (3.38-12.4) versus 6.85% (2.94-10.8); p = 0.8.

CONCLUSIONS

The observed activity of NK cells after in vitro stimulation by IL2, IL-12 and IL15 in children suffering from type 1 diabetes mellitus indicates the tendency for supporting the inhibition of autoimmunological reaction by increased IL10 synthesis and increased number of NK cells with surface NKG2D receptors.

Age-dependent changes of serum soluble CD30 concentration in children

  CD30 was originally described as a marker on Reed-Sternberg cells in Hodgkin lymphoma. The extracellular portion of CD30 is proteolytically cleaved from CD30+ cells, to produce a soluble form of the molecule (sCD30) detectable in serum. Measurement of sCD30 concentration in serum has been suggested to be a potential tool in monitoring of inflammatory status in variety of diseases. Several investigators reported the relevance for sCD30 as a predictive marker for allograft rejection following organ transplantation. The aim of the study was to verify whether sCD30 serum concentrations may be affected by an age in healthy children. Heparinized venous blood was taken from 78 healthy children. For the analysis of sCD30 levels, the commercially available sCD30 ELISA was used. The sCD30 was detected in all serum samples and concentrations ranged from 6.75 to 68.07ng/mL. The statistical analysis of all individuals showed that sCD30 concentration was significantly age depended (r=-0.618, p<0.0001). When sCD30 concentrations were analyzed in regard to gender, no significant differences were identified in age subgroups.

Effects of 1-methylnicotinamide and its metabolite N-methyl-2-pyridone-5-carboxamide on streptozotocin-induced toxicity in murine insulinoma MIN6 cell line

1-methylnicotinamide (MNA) is a primary metabolite of nicotinamide. In recent years several activities of MNA have been described, such as anti-inflammatory activity in skin diseases, induction of prostacyclin synthesis via COX-2, aortal endothelium protection in diabetes and hypertriglyceridaemia and increased survival rate of diabetic rats. 1-methylnicotinamide was also suggested to protect pancreatic cells from streptozotocin in vivo. Streptozotocin toxicity is known to be mediated by poly-ADP-ribose polymerase. Nicotinamide and its derivatives have been shown to ameliorate poly-ADP-ribose polymerase-dependent nucleotide pool reduction. We aimed to verify if 1-methylnicotinamide and its metabolite, N-methyl-2-pyridone-5-carboxamide, can protect insulinoma cells from streptozotocin-induced toxicity. We found that N-methyl-2-pyridone-5-carboxamide, but not 1-methylnicotinamide, restores the pool of ATP and NAD+ in streptozotocin-treated cells, but neither compound improved the cell viability. We conclude that inhibition of poly-ADP-ribose polymerase-dependent nucleotide pool reduction may not be sufficient to protect cells from streptozotocin toxicity.

Effects of 1-methylnicotinamide and its metabolite N-methyl-2-pyridone-5-carboxamide on streptozotocin-induced toxicity in murine insulinoma MIN6 cell line

1-methylnicotinamide (MNA) is a primary metabolite of nicotinamide. In recent years several activities of MNA have been described, such as anti-inflammatory activity in skin diseases, induction of prostacyclin synthesis via COX-2, aortal endothelium protection in diabetes and hypertriglyceridaemia and increased survival rate of diabetic rats. 1-methylnicotinamide was also suggested to protect pancreatic cells from streptozotocin in vivo. Streptozotocin toxicity is known to be mediated by poly-ADP-ribose polymerase. Nicotinamide and its derivatives have been shown to ameliorate poly-ADP-ribose polymerase-dependent nucleotide pool reduction. We aimed to verify if 1-methylnicotinamide and its metabolite, N-methyl-2-pyridone-5-carboxamide, can protect insulinoma cells from streptozotocin-induced toxicity. We found that N-methyl-2-pyridone-5-carboxamide, but not 1-methylnicotinamide, restores the pool of ATP and NAD+ in streptozotocin-treated cells, but neither compound improved the cell viability. We conclude that inhibition of poly-ADP-ribose polymerase-dependent nucleotide pool reduction may not be sufficient to protect cells from streptozotocin toxicity.

The 5'VNTR proinsulin gene (INS) polymorphism and the functional reserve of β cells in the intravenous glucose tolerance test

INTRODUCTION

Proinsulin 5'VNTR polymorphism determines susceptibility to type 1 diabetes (T1DM). The authors tested whether it affects intravenous glucose tolerance test (IVGTT) results.

AIM OF THE STUDY

To evaluate a possible relationship between 5'VNTR proinsulin gene (INS) polymorphism and glucose, insulin and C-peptide levels during IVGTT among siblings of children suffering from T1DM.

MATERIAL AND METHODS

Fourteen patients - siblings of children with type 1 diabetes, positive for at least one autoantibody, underwent IVGTT with glucose, insulin and C-peptide concentrations measurement.

RESULTS

Mean age of patients equaled 10.71 ± 4.15 years. Eight individuals were homozygous for class I/I and six were class III/I heterozygotes. No significant differences in blood glucose levels during the IVGTT were observed (p=0.67). However, lower insulin (p=0.03) and C-peptide (p=0.01) levels were observed in I/I homozygotes in post-challenge timepoints. No significant differences were observed in baseline fasting insulin, glucose and C-peptide levels.

CONCLUSIONS

The class III allele in the 5'VNTR promoter region of INS is associated with a greater functional reserve of β cells in response to a direct hyperglycemic stimulus in individuals with a familial background of T1DM.

FOXP3, IL-10, and TGF-β genes expression in children with IgE-dependent food allergy

Background

Regulatory T cells (Tregs) have an essential role in tolerance and immune regulation. However, few and controversial data have been published to date on the role and number of these cells in food allergic children. The forkhead/winged-helix transcription factor box protein 3 (FOXP3) is considered the most reliable marker for Tregs.

Objective

This study aims to investigate the FOXP3, interleukin (IL)-10, and transforming growth factor (TGF-β) genes expression in children with IgE-dependent food allergy.

Material and Methods

The study group consisted of 54 children with IgE-dependent food allergy (FA) and a control group of 26 non-atopic healthy children. The diagnosis of FA was established using questionnaires, clinical criteria, skin prick tests, serum sIgE antibodies (UniCAP 100 Pharmacia Upjohn), and a double-blind placebo control food challenge. In order to assess gene expression, the isolation of nucleated cells was performed using Histopaque-1077 (Sigma-Aldrich, Germany). The concentration of RNA obtained was measured using a super-sensitive NanoDrop ND1000 spectrophotometer (Thermo Scientific, USA). A reverse transcription reaction was performed using a commercially available set of High Capacity cDNA Archive Kit (Applied Biosystems, USA). Analysis have been carried out in the genetic analyzer 7900HT Real-Time PCR (Applied Biosystems, USA).

Results

The average level of the FOXP3 gene expression in the studied group was 2.19 ± 1.16 and in the control group 2.88 ± 1.66 (p = 0.03). The average level of IL10 mRNA expression in the study group was 13.6 ± 1.07 and was significantly lower than corresponding values in the control group 14.3 ± 1.1 (p = 0.01). There were no significant differences in the average level of the TGF-β mRNA expression in the study group (3.4 ± 0.4) and controls (3.5 ± 0.3; p > 0.05). The FOXP3 gene expression was the highest in children who acquired tolerance to food (3.54 ± 0.75), lower in heated allergen-tolerant children (2.43 ± 0.81), and the lowest in heated allergen-reactive children (1.18 ± 0.5; p = 0.001 control vs heated allergen reactive; p = 0.005 heated allergen tolerant vs heated allergen reactive; p = 0.001 outgrown vs heated allergen reactive). The significant tendency toward lower total IgE levels with a higher FOXP3 mRNA expression was detected (n = 54; Pearson r = −0.4393; p = 0.001).

Conclusions

Children with FA showed statistically significant lower level of the FOXP3 and IL10 gene expression than healthy children. Children acquiring tolerance to the food show significantly higher levels of the FOXP3 gene expression than children with active FA. The correlation between the level of FOXP3 and total IgE was detected.

Evaluation of receptor expression on immune system cells in the peripheral blood of asthmatic children undergoing food challenges

BACKGROUND

The role of food allergens in the induction of allergic reactions in the airways is not completely understood. The aim of the present study was to evaluate fluorocytometric assays of the peripheral blood during food challenge tests in children with asthma and food allergy.

PATIENTS AND METHODS

22 children with asthma and concomitant food allergy and 18 children with asthma without food allergy participated in the study. Oral challenge tests were performed using double-blind, placebo-controlled food challenge. Blood samples were collected before and 4 and 24 h after the challenge. CD25 and CD23 antigen expression was determined with monoclonal antibodies using a FACSCalibur flow.

RESULTS

The evaluation of the CD25+ T subpopulation and CD19+CD23+ B lymphocytes revealed statistically significant differences between the study group and the control group. In children with asthma and food allergy, the cell pool consisted (on average) of 9 +/- 2.8% of CD3+CD25+ cells before the challenge and of 10.3 +/- 3.8% (mean delta: 1.623; p = 0.01) after the provocation. However, placebo challenge did not significantly change the number of this T-lymphocyte subpopulation (mean delta: -0.121; p > 0.05). The highest increase in the CD25+ T-subpopulation expression was found in patients with respiratory reactions during the positive food challenge (mean delta: 4.065; p < 0.004).

CONCLUSIONS

An increase in CD25+ T-lymphocyte and CD23 B-lymphocyte populations after food allergen challenge may indicate their significant role in the pathogenesis of the active phase of the immunoinflammatory process in children with asthma and concomitant food allergy.

Cytokine profile in children with asthma undergoing food challenges

BACKGROUND

The influence of food allergens on the profile of inflammatory markers in children with asthma has not been investigated. To ascertain the influence of food allergens on the intensity of the inflammatory process, a cytokine profile was determined before and after a food challenge test in the peripheral blood of children with asthma and coexistent food allergy.

MATERIAL AND METHODS

We studied 22 children with asthma and immunoglobulin (Ig) E-dependent food allergy. Oral challenge tests were carried out using double-blind placebo-controlled food challenge (DBPCFC). Blood was sampled before, and 4 and 24 hours after the oral challenge test. The inflammatory markers interleukin (IL) 4, IL-5, IL-10, tumor necrosis factor (TNF) a, intereron (IFN)-gamma, sIL-2R, and sCD23 were evaluated. The level of cytokines in serum was determined using a commercial enzyme-linked immunoassay Bender Med Systems (Vienna, Austria).

RESULTS

The median IL-4 level before the challenge test was 23.5 pg/mL, after 4 hours it was 38.8 pg/mL, and after 24 hours it was 35.4 pg/mL. The median IL-5 levels measured at the same time points were 4.6 pg/mL, 5.7 pg/mL, and 7.5 pg/mL. A significant increase in IL-4 and IL-5 levels 4 hours (P = .0006; P = .006) and 24 hours (P = .014; P = .015) after food challenge was observed. No statistically significant differences in the levels of the other cytokines during allergen or placebo challenge tests were recorded.

CONCLUSIONS

Determination of plasma IL-4 and IL-5 levels can be a useful tool for evaluation of the effects of food challenge tests on children with asthma and coexisting IgE-dependent food allergy. The results of determining serum IL-10, TNF-alpha, interleukin (IL) IFN-gamma, sIL-2R, and sCD23 levels during the challenge test are not significant.

Clinical evaluation of proinflammatory cytokine inhibitors (sTNFR I, sTNFR II, IL-1 ra), anti-inflammatory cytokines (IL-10, IL-13) and activation of neutrophils after burn-induced inflammation

The study was aimed at evaluating the involvement of sTNFR I, sTNFR II, IL-1 ra, IL-10, IL-13 and reactive oxygen species (ROS) in systemic inflammatory response syndrome (SIRS) development in severely burned children and at assessing the prognostic value of the immunological markers studied. The study comprised 37 patients (17 burned children and 20 controls). Serum levels of the markers determined by means of ELISA and respiratory burst of neutrophils as well as p55 and p75 tumour necrosis factor-alpha (TNF-alpha) receptor expression using flow cytometry were evaluated twice. The burned children presented significantly higher levels of IL-10 and cytokine inhibitors within the first 6-24 h after injury compared with controls (P < 0.05). The decreased oxygen metabolism of neutrophils and increased TNF-alpha receptor expression were found on admission. Moreover, a significant decrease in initially high sTNFR I, sTNFR II, IL-1 ra, IL-10, IL-13 concentrations (P < 0.05) and reduced expression of TNF-alpha receptors (P < 0.05) were observed after burn therapy, whereas ROS generation evidently augmented (P < 0.05). Four of our children who developed hypovolaemic shock revealed a significantly lower ROS generation and higher concentrations of soluble TNF-alpha receptors and IL-1 ra together with IL-10, IL-13 compared with children with good outcome (P < 0.05). Our results revealed the involvement of both ROS, soluble TNF-alpha receptors and IL-1 ra in the development of SIRS in burned children; their monitoring allows for an assessment of the systemic inflammatory reaction activity. The neutrophil BURSTTEST and IL-1 ra might have been clinically helpful markers of SIRS prognosis.

Influence of interleukin IL-2 and IL-12 + IL-18 on surface expression of immunoglobulin-like receptors KIR2DL1, KIR2DL2, and KIR3DL2 in natural killer cells

Natural killer (NK) cells express killer cell inhibitory receptors (KIRs) that recognize polymorphic class I MHC molecules. In the present study, we analyze the modulatory effect of IL-2 alone or a combination of IL-12 with IL-18 on surface expression of killer cell immunoglobulin-like receptors KIR2DL1, KIR2DL2, and KIR3DL2 in NK cells. Thus, it was found that IL-2 causes a significant increase in the proportion of cells with given studied receptors. Stimulation by a mixture of IL-12 and IL-18 caused significant increase in the fraction of cells with the KIR2DL1 and KIR2DL2, however no significant change in the percentage of cells with KIR3DL2 receptor on their surface was observed. The results of the study show the presence of KIRs on both resting and activated NK cells, this may suggest that KIRs have also an important role in the regulatory processes after activation of this subpopulation of cells.