Raised cord serum immunoglobulin E increases the risk of allergic sensitisation at ages 4 and 10 and asthma at age 10

Prenatal Factors in the Development of Allergic Diseases

Allergic diseases are showing increasing prevalence in Western societies. They are characterized by a heightened reactivity towards otherwise harmless environmental stimuli. Allergic diseases showing a wide range of severity of symptoms have a significant impact on the quality of life of affected individuals. This study aims to highlight the mechanisms that induce these reactions, how they progress, and which prenatal factors influence their development. Most frequently, the reaction is mediated by immunoglobulin E (IgE) produced by B cells, which binds to the surface of mast cells and basophils and triggers an inflammatory response. The antibody response is triggered by a shift in T-cell immune response. The symptoms often start in early childhood with eczema or atopic dermatitis and progress to allergic asthma in adolescence. An important determinant of allergic diseases seems to be parental, especially maternal history of allergy. Around 30% of children of allergic mothers develop allergic sensitization in childhood. Genes involved in the regulation of the epithelial barrier function and the T-cell response were found to affect the predisposition to developing allergic disorders. Cord blood IgE was found to be a promising predictor of allergic disease development. Fetal B cells produce IgE starting at the 20th gestation week. These fetal B cells could be sensitized together with mast cells by maternal IgE and IgE-allergen complexes crossing the placental barrier via the low-affinity IgE receptor. Various factors were found to facilitate these sensitizations, including pesticides, drugs, exposure to cigarette smoke and maternal uncontrolled asthma. Prenatal exposure to microbial infections and maternal IgG appeared to play a role in the regulation of T-cell response, indicating a protective effect against allergy development. Additional preventive factors were dietary intake of vitamin D and omega 3 fatty acids as well as decreased maternal IgE levels. The effect of exposure to food allergens during pregnancy was inconclusive, with studies having found both sensitizing and protective effects. In conclusion, prenatal factors including genetics, epigenetics and fetal environmental factors have an important role in the development of allergic disorders in later life. Children with a genetic predisposition are at risk when exposed to cigarette smoke as well as increased maternal IgE in the prenatal period. Maternal diet during pregnancy and immunization against certain allergens could help in the prevention of allergy in predisposed children.

Cord blood IgE predicts allergic sensitization, elevation of exhaled nitric oxide, and asthma in schoolchildren

BACKGROUND

Few data are available in Asian children regarding the validity of cord blood immunoglobulin E (IgE) in predicting allergic sensitization and pulmonary function. The relationship between cord blood IgE and fraction of exhaled nitric oxide (FeNO) remains unknown. This study investigated the associations of cord blood IgE with allergic sensitization, FeNO, pulmonary function, and allergic diseases in Asian children.

METHODS

Five hundred and sixty-six Asian children with valid cord blood IgE measurements at birth participated a 6-year follow-up visit including a questionnaire, serum total and allergen-specific IgE, FeNO measurement, and spirometry. Regression-based analyses with covariates adjustment were applied.

RESULTS

Cord blood IgE levels were significantly associated with FeNO levels (β = 0.131, p < .001) and serum total IgE levels (β = 0.325, p < .001). Cord blood IgE levels were positively associated with allergic sensitization (adjusted odds ratio [AOR] = 2.22, p < .001), and sensitization to mites (p = .002), animals (p = .023), and foods (p = .048). Subjects with cord blood IgE ≥0.24 kU/L (the optimal cutoff) were significantly associated with an increased risk of allergic sensitization (AOR = 2.63, p < .001) and asthma (AOR = 2.35, p = .024) than those with cord blood IgE <0.24 kU/L. Subjects with cord blood IgE ≥0.24 kU/L had significantly higher FeNO levels than those with cord blood IgE <0.24 kU/L (p = .028). There were no significant associations between cord blood IgE levels and pulmonary function parameters.

CONCLUSION

Cord blood IgE ≥0.24 kU/L predicts allergic sensitization, FeNO elevation, and asthma among Asian schoolchildren, suggesting cord blood IgE would be useful for identifying newborns at risk of subsequent allergic sensitization and allergic airway inflammation.

Prenatal Exposure to Di-Ethyl Phthalate (DEP) Is Related to Increasing Neonatal IgE Levels and the Altering of the Immune Polarization of Helper-T Cells

Introduction: Phthalates are substances that are added to plastic products to increase their plasticity. These substances are released easily into the environment and can act as endocrine disruptors. Epidemiological studies in children have showed inconsistent findings regarding the relationship between prenatal or postnatal exposure to phthalates and the risk of allergic disease. Our hypothesis is that prenatal exposure to phthalates may contribute to the development of allergies in children. Material and methods: The objective of this study was to determine the associations between urinary phthalate metabolite concentrations in pregnant women, maternal atopic diathesis, maternal lifestyle, and cord blood IgE. Pregnant mothers and paired newborns (n = 101) were enrolled from an antenatal clinic. The epidemiologic data and the clinical information were collected using standard questionnaires and medical records. The maternal blood and urine samples were collected at 24–28 weeks gestation, and cord blood IgE, IL-12p70, IL-4, and IL-10 levels were determined from the newborns at birth. The link between phthalates and maternal IgE was also assessed. To investigate the effects of phthalates on neonatal immunity, cord blood mononuclear cells (MNCs) were used for cytokine induction in another in vitro experiment. Results: We found that maternal urine monoethyl phthalate (MEP) (a metabolite of di-ethyl phthalate (DEP)) concentrations are positively correlated with the cord blood IgE of the corresponding newborns. The cord blood IL-12p70 levels of mothers with higher maternal urine MEP groups (high DEP exposure) were lower than mothers with low DEP exposure. In vitro experiments demonstrated that DEP could enhance IL-4 production of cord blood MNCs rather than adult MNCs. Conclusion: Prenatal DEP exposure is related to neonatal IgE level and alternation of cytokines relevant to Th1/Th2 polarization. This suggests the existence of a link between prenatal exposure to specific plasticizers and the future development of allergies.

Maternal diesel particle exposure promotes offspring asthma through NK cell-derived granzyme B

Mothers living near high-traffic roads before or during pregnancy are more likely to have children with asthma. Mechanisms are unknown. Using a mouse model, here we showed that maternal exposure to diesel exhaust particles (DEP) predisposed offspring to allergic airway disease (AAD, murine counterpart of human asthma) through programming of their NK cells; predisposition to AAD did not develop in DEP pups that lacked NK cells and was induced in normal pups receiving NK cells from WT DEP pups. DEP NK cells expressed GATA3 and cosecreted IL-13 and the killer protease granzyme B in response to allergen challenge. Extracellular granzyme B did not kill, but instead stimulated protease-activated receptor 2 (PAR2) to cooperate with IL-13 in the induction of IL-25 in airway epithelial cells. Through loss-of-function and reconstitution experiments in pups, we showed that NK cells and granzyme B were required for IL-25 induction and activation of the type 2 immune response and that IL-25 mediated NK cell effects on type 2 response and AAD. Finally, experiments using human cord blood and airway epithelial cells suggested that DEP might induce an identical pathway in humans. Collectively, we describe an NK cell-dependent endotype of AAD that emerged in early life as a result of maternal exposure to DEP.

Sex-moderated interactions between IL4/IL13 pathway genes and prenatal environment on cord blood IgE levels

BACKGROUND

Elevated cord blood IgE (cIgE), a predictor of atopic diseases, is influenced by genetic and environmental factors. However, gene-environment interactions on cIgE elevation and their difference by sex remain largely unexplored.

OBJECTIVE

This study aimed to determine whether there are sex-moderated interactions between genetic variants in the IL4/IL13 pathway and prenatal environments on cIgE elevation.

METHODS

Comprehensive information on environmental tobacco smoke (ETS), home dampness (indexed by combining mildewy odour, visible mould and water stamp on the wall) and other household environments was obtained using a structured questionnaire during the third trimester of pregnancy in 1107 full-term newborns. The cord blood was collected for measuring cIgE levels, with elevation defined as ≥0.5 IU/mL, and for genotyping of five single nucleotide polymorphisms of three candidate genes (IL-13 rs1800925, rs20541, rs848, IL-4 rs2243250 and STAT6 rs324011).

RESULTS

Gene-environment interactions on cIgE elevation were observed in male but not female newborns, including those between ETS and IL13 rs20541, between home dampness and STAT6 rs324011, and between composite environmental exposure (combined ETS and the three home dampness indices) and STAT6 rs324011 (P for interaction = 0.03, 0.006, and 0.001, respectively). Male newborns carrying STAT6 rs324011 CT or TT genotype manifested with a significant dose-response association of the composite environmental exposure with cIgE elevation.

CONCLUSION AND CLINICAL RELEVANCE

Sex moderates the gene-environment interactions involving IL4/IL13 pathway genes and prenatal household environments on cIgE elevation. The absence of prenatal exposure to ETS and home dampness in male neonates carrying the STAT6 rs324011 CT or TT genotype is least likely associated with cIgE elevation.

IgE level in newborn umbilical cord and its relationship with some maternal factors

BACKGROUND AND OBJECTIVES

Allergic diseases are among major pediatric issues as they are highly prevalent and chronic. Therefore, identification of factors contributing to allergic disease could play a significant role in prevention of these conditions. This study aimed at investigating the IgE level in newborn's umbilical cord blood and its relationship with some maternal factors.

METHODS

A cross-sectional study was conducted in 101 mothers and their newborns in Babol, Iran 2016. The samples were selected using non-probability convenience sampling. Information including newborn sex, gravidity, history of allergy before and during pregnancy (asthma, allergic rhinitis, eczema, hives, food allergy, and drug allergy), family history of allergy among mothers, history of exposure to secondhand smoke and pets, and delivery techniques was recorded. The IgE levels in newborn umbilical cord blood and maternal serum were measured using an IgE kit and ELISA technique.

RESULTS

The newborns included 53 females (52.5%) and 29 mothers had vaginal birth (28.7%). History of exposure to secondhand smoke was found in 15 samples (14.9%), and 18 participants reported exposure to pets (17.8%). The median IgE levels in newborns and their mothers were 0.41 and 98.6, respectively. In general, IgE level in all newborns was within the normal range, but, it was higher than normal in 15 mothers (14.9%). The IgE level was significantly higher in male newborns than that of the female newborns (p = 0.011). There were no significant differences in the IgE levels of mothers and their newborns on the basis of delivery technique and history of exposure to pets (p > 0.05).

CONCLUSION

In this study, the IgE level in all newborns was within the normal range, and sex was found to be an effective factor in IgE levels.

Effect of season of birth on cord blood IgE and IgE at birth: A systematic review and meta-analysis

BACKGROUND

Elevated cord blood IgE is important on the pathway to allergic disease. The association between season of birth and infant cord blood IgE is not well-established. Study findings differ on which birth season is associated with higher cord blood IgE risk and its magnitude. We conducted a systematic review and meta-analysis of studies on season of birth and cord blood IgE.

METHODS

We searched Medline, Web of Science, Scopus and ProQuest Health databases, and reviewed reference lists of articles that met the inclusion criteria. All included studies measured IgE as a binary variable using various cut-off values. We performed multivariate-random-effects meta-analysis to handle an exposure with multiple categories of Season of Birth.

RESULTS

Our search identified 275 records and 10 had sufficient data to be included in a meta-analysis. Relative to summer, winter birth had the greatest odds of high IgE (≥ 0.1IU/ml), meta-analysis OR = 1.24 (95%CI: 1.01-1.52). A similar OR, was found for IgE ≥ 0.5 IU/ml, OR = 1.30 (95%CI: 0.99-1.71).

CONCLUSIONS

A winter season of birth was associated with statistically significant higher odds of elevated cord blood IgE at cut-off ≥ 0.1IU/ml but borderline at cut-off ≥ 0.5IU/ml. This winter effect is likely to be a marker for a range of other environmental exposures during specific stages of pregnancy, such as aeroallergen exposures, maternal infections and vitamin D levels. Further research is required to support our finding and to identify the exact mechanisms that lead to the winter season of birth effect on circulating IgE levels, as this may have implications for allergic disease prevention.

Air Pollution During Pregnancy and Cord Blood Immune System Biomarkers

OBJECTIVES

We aimed to determine whether average and trimester-specific exposures to ambient measures of nitrogen dioxide (NO2) and particular matter (PM2.5) were associated with elevated cord blood concentrations of immunoglobulin E (IgE) and two epithelial cell produced cytokines: interleukin-33 (IL-33) and thymic stromal lymphopoietin (TSLP).

METHODS

This study utilized data and biospecimens from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study. There were 2001 pregnant women recruited between 2008 and 2011 from 10 Canadian cities. Maternal exposure to NO2 and PM2.5 was estimated using land use regression and satellite-derived models.

RESULTS

We observed statistically significant associations between maternal NO2 exposure and elevated cord blood concentrations of both IL-33 and TSLP among girls but not boys.

CONCLUSIONS

Maternal NO2 exposure may impact the development of the newborn immune system as measured by cord blood concentrations of two cytokines.

Prenatal triclosan exposure and cord blood immune system biomarkers

Triclosan is widely used as an antimicrobial agent and preservative that has been hypothesized to play a role in asthma and allergic disease. The limited body of literature regarding the allergenicity of triclosan has not evaluated prenatal exposure and subsequent potential effects on the developing immune system. The objective of the present study was to determine the association between prenatal urinary triclosan concentrations and cord blood immune system biomarker concentrations. Umbilical cord blood samples were obtained from the Maternal-Infant Research on Environmental Chemicals (MIREC) Biobank and were tested for three immune system biomarkers: immunoglobulin E (IgE), thymic stromal lymphopoietin (TSLP), and interleukin-33 (IL-33). Triclosan concentrations were measured in urine at 6-13 weeks gestation. No statistically significant associations were observed between prenatal triclosan concentrations and elevated concentrations of any immune system biomarker (n=1219 participants). Longitudinal studies are necessary to determine how the observed findings at birth translate into childhood.

Prenatal exposure to phthalates, bisphenol A and perfluoroalkyl substances and cord blood levels of IgE, TSLP and IL-33

The fetal time period is a critical window of immune system development and resulting heightened susceptibility to the adverse effects of environmental exposures. Epidemiologists and toxicologists have hypothesized that phthalates, bisphenol A (BPA) and perfluoroalkyl substance have immunotoxic properties. Immunotoxic effects of chemicals may manifest in an altered immune system profile at birth. Immunoglobulin E, thymic stromal lymphopoietin (TSLP), and interleukin-33 (IL-33) are integral in the etiology of childhood allergy and detectable at birth. The objective of this study was to determine the association between maternal levels of phthalates, bisphenol A (BPA), and perfluoroalkyl substances and elevated umbilical cord blood levels of IgE, TSLP, and IL-33. This study utilized data collected in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, a trans-Canada cohort study of 2001 pregnant women. Of these women, 1258 had a singleton, term birth and cord blood sample. A Bayesian hierarchical model was employed to determine associations between log-transformed continuous variables and immune system biomarkers while adjusting for potential confounding from correlated environmental contaminants. Inverse, nonlinear associations were observed between maternal urinary MCPP levels and elevated levels of both IL-33/TSLP and IgE and between maternal urinary BPA levels and elevated levels of IL-33/TSLP. In this primarily urban Canadian population of pregnant women and their newborns, maternal urinary and plasma concentrations of phthalate metabolites, BPA, and perfluoroalkyl substances were not associated with immunotoxic effects that manifest as increased odds of elevated levels of IgE, TSLP or IL-33.

Maternal exposure to metals and persistent pollutants and cord blood immune system biomarkers

BACKGROUND

The fetal time period is a critical window of immune system development and resulting heightened susceptibility to the adverse effects of environmental exposures. Epidemiologists and toxicologists have hypothesized that persistent organic pollutants, pesticides and metals have immunotoxic properties. Immunotoxic effects may manifest as an altered immune system profile at birth. Immunoglobulin E, thymic stromal lymphopoietin (TSLP), and interleukin-33 (IL-33) may be implicated in the etiology of childhood allergy and are detectable at birth. The objective of this study was to examine the potential relationship between maternal concentrations of metals, persistent organic pollutants, and pesticides and elevated umbilical cord blood concentrations of IgE, TSLP, and IL-33 in a Canadian birth cohort.

METHODS

This study utilized data collected in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, a trans-Canada cohort study of 2,001 pregnant women. Of these women, 1258 had a singleton, term birth and cord blood sample. Logistic regression was used to determine associations between log-transformed continuous variables and immune system biomarkers.

RESULTS

Inverse relationships were observed between lead, DDE, PCB-118, and a summary index of organophosphorous metabolites and jointly elevated concentrations of IL-33 and TSLP. None of the environmental contaminants were associated with increased odds of a high cord blood immune system biomarker concentration.

CONCLUSIONS

In this primarily urban Canadian population of pregnant women and their newborns, maternal blood or urine concentrations of persistent organic pollutants, pesticides, and metals were not associated with immunotoxic effects that manifest as increased odds of elevated concentrations of IgE, TSLP or IL-33.

Can family history and cord blood IgE predict sensitization and allergic diseases up to adulthood?

BACKGROUND

Long-term studies of the predictive value of family history and cord blood IgE level until adulthood are few, and their conclusions have been contradictory.

METHODS

Screening of total IgE in 1617 cord blood samples was performed in a Danish birth cohort. All infants with cord blood IgE (CB-IgE) ≥ 0.5 kU/l and a corresponding randomly chosen group with CB-IgE <0.5 kU/l were chosen for follow-up. Questionnaire-based interviews, physical examination, specific IgE testing, and from 10 yr also spirometry, were carried out at 1½, 5, 10, 15, and 26 yr. Predefined diagnostic criteria were used.

RESULTS

A total of 455 infants were included, 188 with CB-IgE ≥ 0.5 kU/l and 267 with CB-IgE <0.5 kU/l. Follow-up rates were high, 288 (63%) attended the 26-yr follow-up. Family history and elevated CB-IgE were significantly associated to allergic disease until 26 yr. Concerning any allergic symptoms at 1½ yr the positive and negative predictive values (PPV and NPV), the sensitivity and specificity of CB-IgE ≥ 0.5 kU/l, was 29%, 81%, 54%, and 61%, respectively. The corresponding figures at 26 yr were 46%, 62%, 43%, and 65%. Overall, family history as well as CB-IgE ≥ 0.5 kU/l was associated with high NPV and specificity, but low PPV and sensitivity.

CONCLUSION

Although family history and elevated CB-IgE were significantly associated with primarily atopic disease until 26 yr, none of these were strong predictors for subsequent sensitization and allergic symptoms from childhood until early adulthood. It appears that the predictive capacity of CB-IgE decreases in adolescence and early adulthood.

Irreversible airway obstruction in asthma: what we lose, we lose early

Asthma, a syndrome manifested by airway inflammation and obstruction, globally contributes significantly to morbidity and mortality. Although current evidence identifies risk factors that evoke asthma, critical questions concerning susceptibility factors that induce severe persistent disease remain unclear. Early onset of asthma decreases lung function that may be unrecognized until later in adulthood when patients experience dyspnea on exertion and attenuated quality of life. This review highlights current evidence in predicting the onset of asthma and identifying those patients at greatest risk for severe persistent disease.

Different genetic associations of the IgE production among fetus, infancy and childhood

Elevation of serum IgE levels has long been associated with allergic diseases. Many genes have been linked to IgE production, but few have been linked to the developmental aspects of genetic association with IgE production. To clarify developmental genetic association, we investigated what genes and gene-gene interactions affect IgE levels among fetus, infancy and childhood in Taiwan individuals. A birth cohort of 571 children with completion of IgE measurements from newborn to 1.5, 3, and 6 years of age was subject to genetic association analysis on the 384-customized SNPs of 159 allergy candidate genes. Fifty-three SNPs in 37 genes on innate and adaptive immunity, and stress and response were associated with IgE production. Polymorphisms of the IL13, and the HLA-DPA1 and HLA-DQA1 were, respectively, the most significantly associated with the IgE production at newborn and 6 years of age. Analyses of gene-gene interactions indentified that the combination of NPSR1, rs324981 TT with FGF1, rs2282797 CC had the highest risk (85.7%) of IgE elevation at 1.5 years of age (P = 1.46×10⁻⁴). The combination of IL13, CYFIP2 and PDE2A was significantly associated with IgE elevation at 3 years of age (P = 5.98×10⁻⁷), and the combination of CLEC2D, COLEC11 and CCL2 was significantly associated with IgE elevation at 6 years of age (P = 6.65×10⁻⁷). Our study showed that the genetic association profiles of the IgE production among fetus, infancy and childhood are different. Genetic markers for early prediction and prevention of allergic sensitization may rely on age-based genetic association profiles.

Asthma Heredity, Cord Blood IgE and Asthma-Related Symptoms and Medication in Adulthood: A Long-Term Follow-Up in a Swedish Birth Cohort

Cord blood IgE has previously been studied as a possible predictor of asthma and allergic diseases. Results from different studies have been contradictory, and most have focused on high-risk infants and early infancy. Few studies have followed their study population into adulthood. This study assessed whether cord blood IgE levels and a family history of asthma were associated with, and could predict, asthma medication and allergy-related respiratory symptoms in adults. A follow-up was carried out in a Swedish birth cohort comprising 1,701 consecutively born children. In all, 1,661 individuals could be linked to the Swedish Prescribed Drug Register and the Medical Birth Register, and 1,227 responded to a postal questionnaire. Cord blood IgE and family history of asthma were correlated with reported respiratory symptoms and dispensed asthma medication at 32-34 years. Elevated cord blood IgE was associated with a two- to threefold increased risk of pollen-induced respiratory symptoms and dispensed anti-inflammatory asthma medication. Similarly, a family history of asthma was associated with an increased risk of pollen-induced respiratory symptoms and anti-inflammatory medication. However, only 8% of the individuals with elevated cord blood IgE or a family history of asthma in infancy could be linked to current dispensation of anti-inflammatory asthma medication at follow-up. In all, 49 out of 60 individuals with dispensed anti-inflammatory asthma medication at 32-34 years of age had not been reported having asthma at previous check-ups of the cohort during childhood. Among those, only 5% with elevated cord blood IgE and 6% with a family history of asthma in infancy could be linked to current dispensation of anti-inflammatory asthma medication as adults. Elevated cord blood IgE and a positive family history of asthma were associated with reported respiratory symptoms and dispensed asthma medication in adulthood, but their predictive power was poor in this long-time follow-up.

Trends in cutaneous sensitization in the first 18 years of life: results from the 1989 Isle of Wight birth cohort study

BACKGROUND

Skin prick testing (SPT) is fundamental to the practice of clinical allergy identifying relevant allergens and predicting the clinical expression of disease. There are only limited data on the natural history of SPT results over childhood and adolescence.

OBJECTIVE

We aimed to describe the natural history of SPT and patterns of sensitization over childhood and adolescence.

METHODS

The 1989 Isle of Wight birth cohort (1456 participants) was followed up at 1, 2, 4, 10 and 18 years. SPT was undertaken from 4 years.

RESULTS

SPT was performed on 980 (80%), 1036 (75%) and 853 (65%) of participants at 4, 10 and 18 years. The prevalence of sensitization to any allergen at these time-points was 19.7%, 26.9% and 41.3% respectively. At each time-point, boys were significantly more likely to be sensitized (P < 0.016) and sensitization significantly increased over childhood and adolescence (average annual increase of 7%). Some children outgrew their sensitization. The rate of sensitization to most individual allergens increased over childhood and adolescence. A configural frequency analysis showed that whether an individual was sensitizated was relatively fixed over childhood and adolescence. Cluster analysis at 4 years demonstrated four major groups of individuals with similar co-sensitization to specific allergens. Children who were sensitized at age 4 years generally went onto become sensitized to additional allergens at 10 and 18 years.

CONCLUSIONS AND CLINICAL RELEVANCE

Allergic sensitization continues to increase over childhood into adolescence although the majority of children who were not sensitized at 4 years remain non-sensitized throughout childhood and adolescence. The presence of sensitization at 4 years predicted later sensitization to additional allergens.

Allergy sensitization and asthma among 13-14 year old school children in Nigeria

BACKGROUND

The prevalence of asthma and role of atopy in asthma among children has not been clearly defined in Nigeria.

OBJECTIVE

To determine the prevalence of asthma and investigate risk factors related to allergy sensitization among urban and rural school children in southwest Nigeria.

METHODS

Validated ISAAC questionnaire was administered to 1736 high school children in randomly selected schools in rural and urban communities. Identified asthma cases were matched to controls. Allergy skin tests, blood eosinophil count, serum IgE and stool examination for parasites were performed. Dust samples from homes were also collected and analyzed for allergens.

RESULTS

The prevalence of asthma was 7.5% (95% CI 6.0 to 9.2%) and 8% (95% CI 6.0-10.4%) in the rural and urban communities respectively . Risk factors for asthma included cigarette-smoking, cats in the home and family size. Eosinophil count (109/L) was elevated in asthmatics [0.70 (95% CI 0.48-1.11) vs. 0.32 (95% CI 0.19-0.69); p<0.01], but IgE levels were similar between the two groups (298±229 IU/mL vs. 288±257; p=0.97). Positive skin tests to cat hair, cockroach, mango blossom and mouse epithelium were more frequent in asthmatics than in healthy controls, especially in the rural communities. There was no correlation between allergens in dust collected from homes and skin test reactivity.

CONCLUSION

Asthma prevalence is similar in rural and urban children in Southwest Nigeria and atopy with elevated IgE was not observed to be a major factor for asthma in our cohort of children in both communities.

Intrauterine sensitization of allergen-specific IgE analyzed by a highly sensitive new allergen microarray

BACKGROUND

To design a rational allergy prevention program, it is important to determine whether allergic sensitization starts in utero under the maternal immune system.

OBJECTIVE

To investigate the origin of allergen-specific IgE antibodies in cord blood (CB) and maternofetal transfer of immunoglobulins.

METHODS

The levels of food and inhalant allergen-specific IgE, IgA, IgG, and IgG(4) antibodies in CB and maternal blood (MB) from 92 paired neonates and mothers were measured by using a novel allergen microarray of diamond-like-carbon-coated chip, with high-sensitivity detection of allergen-specific antibodies and allergen profiles.

RESULTS

The levels of allergen-specific IgE antibodies against food and inhalant allergens and allergen profiles were identical in CB and newborn blood, but the levels and profiles, specifically against inhalant allergens, were different from those in MB. The level of allergen-specific IgA antibodies was below the detection levels in CB despite clear detection in MB. Therefore, contamination with MB in CB was excluded on the basis of extremely low levels of IgA antibodies in CB and the obvious mismatch of the allergen-specific IgE and IgA profiles between CB and MB. However, the levels of allergen-specific IgG and IgG(4) antibodies and their allergen profiles were almost identical in both MB and CB.

CONCLUSION

Allergen-specific levels of IgE and IgA antibodies and their allergen profiles analyzed by the diamond-like-carbon allergen chip indicate that IgE antibodies in CB are of fetal origin. Food-allergen specific IgE antibodies were detected more often than inhalant-allergen specific IgE antibodies in CB, the reason of which remains unclarified.

Perinatal gene-gene and gene-environment interactions on IgE production and asthma development

Atopic asthma is a complex disease associated with IgE-mediated immune reactions. Numerous genome-wide studies identified more than 100 genes in 22 chromosomes associated with atopic asthma, and different genetic backgrounds in different environments could modulate susceptibility to atopic asthma. Current knowledge emphasizes the effect of tobacco smoke on the development of childhood asthma. This suggests that asthma, although heritable, is significantly affected by gene-gene and gene-environment interactions. Evidence has recently shown that molecular mechanism of a complex disease may be limited to not only DNA sequence differences, but also gene-environmental interactions for epigenetic difference. This paper reviews and summarizes how gene-gene and gene-environment interactions affect IgE production and the development of atopic asthma in prenatal and childhood stages. Based on the mechanisms responsible for perinatal gene-environment interactions on IgE production and development of asthma, we formulate several potential strategies to prevent the development of asthma in the perinatal stage.

Different implications of paternal and maternal atopy for perinatal IgE production and asthma development

Asthma is a hereditary disease associated with IgE-mediated reaction. Whether maternal atopy and paternal atopy have different impacts on perinatal IgE production and asthma development remains unclear. This paper reviews and summarizes the effects of maternal and paternal atopy on the developmental aspects of IgE production and asthma. Maternal atopy affects both pre- and postnatal IgE production, whereas paternal atopy mainly affects the latter. Maternally transmitted genes GSTP1 and FceRI-beta are associated with lung function and allergic sensitization, respectively. In IgE production and asthma development, the maternal influence on gene-environment interaction is greater than paternal influence. Maternal, paternal, and/or postnatal environmental modulation of allergic responses have been linked to epigenetic mechanisms, which may be good targets for early prevention of asthma.

Prediction of atopic dermatitis in 2-yr-old children by cord blood IgE, genetic polymorphisms in cytokine genes, and maternal mentality during pregnancy

Atopic dermatitis (AD) is the most common skin disease in childhood and the first step of atopic march. This study aimed to investigate whether AD in children could be better predicted by biologic markers (cord blood IgE [cbIgE], LT-αNcoI alleles, and FcεRI-β E237G genotypes) and maternal mentality during pregnancy, taking into account gender, socio-demographic factors, and parental atopy. From 2001 to 2005, 1264 mother-infant pairs were recruited to participate in a birth cohort study. Prenatal questionnaire was used to collect family history, maternal gestational conditions and mentality, and environmental exposures. Cord blood was collected and assayed for genotypes and IgE levels. Phone interviews at 6 months and 2 yrs of age were conducted to inquire children's health status, including AD occurrence. In addition to the known risk factors such as gender, maternal education, and parental atopy, biomarkers and maternal mentality during pregnancy were screened by logistic regression as candidate predictors of AD. Area-under-curve (AUC) statistic from receiver-operating characteristic (ROC) curve analysis was used to compare two predicting models with and without biomarkers and maternal mentality. A total of 730 pairs completed the prenatal questionnaire and phone interview and were included in final analysis. The prevalence of ever having physician-diagnosed AD by 2-yr-olds was 5.9%. Elevated cbIgE levels (≥0.5 kU/l), LT-αNcoI alleles, FcεRI-β E237G genotype, and maternal psychologic stress during pregnancy were significantly associated with AD. Comparison with AUCs of the classic model (including gender, maternal education, and parental atopy), the model adding cbIgE levels, genotypes in cytokine genes, and maternal stress (model 2) showed higher ability to discriminate between children with and without AD (AUC statistics: 0.63 [95% CI = 0.60-0.67] vs. 0.73 [95% CI = 0.70-0.76], respectively; model comparison, p = 0.027). We conclude that elevated cbIgE, LT-α and FcεRI-β genotypes, and maternal stress during pregnancy were associated with ever having physician-diagnosed AD in 2-yr-old children and increased the predictive ability for AD after taking into account gender, maternal education, and parental atopic history.

Maternal immunization to modulate the development of allergic response and pathogen infections

This article reviews recent experimental approaches of preventive strategies regarding allergy and infections by pathogens, particularly in early childhood, by targeting maternal immunomodulation. Basic research is essential to understand maternal vaccination as a strategy to control allergic disease and bacterial and viral infections; thus, providing support for future translational research. The environmental stimuli and host genetic factors, along with maternal influences in early life when immune systems are developing and during postnatal life, are essential for the decision between tolerance induction or allergen sensitization. Maternal immunomodulation strategies should serve as a challenge when attempting to halt the spread of allergy responses and viral infections, until the innate and adaptive arms of the immune system of the neonates are competent.

The relationship between cord blood immunoglobulin E levels and allergy-related outcomes in young adults

BACKGROUND

Elevated cord blood IgE may be associated with a higher risk of allergic disease.

OBJECTIVE

To determine whether cord blood IgE is associated with allergic biomarkers or allergic disorders in young adults.

METHODS

Data was collected from 670 subjects 18-21 years of age that were among 835 original participants in the Detroit Childhood Allergy Study, a general risk, population-based birth cohort. Cord blood IgE was assessed in relation to biomarkers associated with allergy and asthma including total IgE, allergen-specific IgE, blood eosinophilia, and spirometry. Cord blood IgE was also analyzed for associations to subsequent allergic disease including atopic dermatitis, allergic rhinitis, and asthma.

RESULTS

Cord blood IgE, analyzed as a continuous measure, was modestly correlated with total IgE (r = 0.18, P < .001) and higher cord IgE was associated with a higher likelihood of sensitization to common allergens in young adults (OR = 1.18, 95% CI, 1.02-1.37; P = .031). The relationship between cord IgE and sensitization was stronger among teens with no pet exposure in the first year of life (OR = 1.43, 95% CI, 1.16-1.77; P = .001). No relationship was found between cord IgE and blood eosinophil counts or lung function. In addition, no consistent association of cord blood IgE to asthma, allergic rhinitis, or atopic dermatitis was apparent.

CONCLUSIONS

An elevated cord blood IgE level modestly correlates with elevated total IgE and is associated with a slightly higher likelihood of allergic sensitization among young adults. However, cord IgE is not a strong predictor of clinical allergic disorders in this age group.

Does genetic regulation of IgE begin in utero? Evidence from T(H)1/T(H)2 gene polymorphisms and cord blood total IgE

BACKGROUND

Elucidation of early life factors is critical to understand the development of allergic diseases, especially those manifesting in early life such as food allergies and atopic dermatitis. Cord blood IgE (CBIgE) is a recognized risk factor for the subsequent development of allergic diseases. In contrast with numerous genetic studies of total serum IgE in children and adults, limited genetic studies on CBIgE have been conducted.

OBJECTIVE

To test the associations between functional or tagging single nucleotide polymorphisms (SNPs) in genes involved in the T(H)1/T(H)2 pathway and CBIgE in a large US inner-city birth cohort.

METHODS

CBIgE, measured by Phadia ImmnunoCAP, was analyzed as a continuous and a binary variable. The association of each SNP with the 2 outcomes was tested using tobit and logistic regression models, respectively, with adjustment for pertinent covariates, ancestral proportion, and multiple testing. Ethnic heterogeneity and gene-gene interactions were also explored.

RESULTS

Three SNPs (rs1800925, rs2069743, and rs1295686) in the IL13 gene were significantly associated with CBIgE concentration (P ≤ 6 × 10(-4), FDR-corrected P < .05). These SNPs jointly influenced CBIgE in a dose-response manner (P for trend = 9 × 10(-8)). Significant associations also were observed for SNPs in the IL-13 receptor α1 (rs5956080) and signal transducer and activator of transcription 6 (rs11172106) genes. Ethnicity-specific genetic effects were observed for SNPs in the IL5 and GATA3 genes. Several gene-gene interactions (including IL13-IL4 receptor and IL13-signal transducer and activator of transcription 6 interactions) were detected in relation to CBIgE.

CONCLUSION

Our data demonstrated that multiple SNPs were individually and jointly associated with CBIgE, with evidence of gene-gene interactions and ethnic heterogeneity. These findings suggest that genetic regulation of IgE may begin in utero.

Can childhood asthma be predicted at birth?

BACKGROUND

Early life appears optimal for prevention of asthma, but interventions require a relevant target population, to date not clearly identified at birth.

OBJECTIVE

We therefore aimed to identify the predicting capacity of factors known around birth for asthma and rhinitis at 10 years.

METHODS

The included 614 healthy term babies with lung function measured at birth in the 1992/1993 Environment and Childhood Asthma study in Oslo attended a 10-year follow-up visit including a structured interview and skin prick test (SPT) for allergies. The logistic regression analyses included 37 general variables from an extensive birth questionnaire; lung function; cord blood total immunoglobulin E and soluble CD14. A history of asthma, current asthma, history of rhinitis and 'healthy' (no history of asthma, rhinitis and negative SPT) was predicted on a group level and individual predicted probabilities were calculated.

RESULTS

The predictability of the models [area under the curve (95% confidence intervals)] was 0.74 (0.69, 0.79), 0.72 (0.64, 0.78), 0.69 (0.54, 0.72) and 0.67 (0.62, 0.71) for a history of asthma, current asthma, rhinitis and 'healthy', respectively. The best model predicted a history of asthma correctly in 93/124 (75%), and incorrectly in 176/490 (36%) children without asthma. The positive predictive values for all outcomes were low (19-61), the highest predicting healthy.

CONCLUSION

Although at best 75% of children with a history of asthma could be predicted at birth, an intervention applied to our predicted high-risk children would be started more often in children without than with future disease. Parental allergic disease alone appears insufficient to identify high-risk populations in future studies of asthma and allergic disease.

Effect of household pet ownership on infant immune response and subsequent sensitization

Sensitization to pets is a major risk factor for asthma. There are many reports on the relationship between household pets, sensitization to the pet, and sensitization to other allergens, often with conflicting results. Pet ownership is not random, and household pets are associated with exposures other than pet allergens. We will review some of the evidence regarding the effects of household pets on infant immune responses, focusing on data from birth cohort studies. It remains unclear precisely why some children develop specific sensitizations to pets whilst others do not in the face of equivalent exposures, but it is likely to be due to gene-environment interactions. Further long-term follow-up of children in whom neonatal and infant immune responses have been measured is necessary to understand how these events occur and how they relate to subsequent disease.

Cord blood versus age 5 mononuclear cell proliferation on IgE and asthma

BACKGROUND

Fetal immune responses following exposure of mothers to allergens during pregnancy may influence the subsequent risk of childhood asthma. However, the association of allergen-induced cord blood mononuclear cell (CBMC) proliferation and cytokine production with later allergic immune responses and asthma has been controversial. Our objective was to compare indoor allergen-induced CBMC with age 5 peripheral blood mononuclear cell (PBMC) proliferation and determine which may be associated with age 5 allergic immune responses and asthma in an inner city cohort.

METHODS

As part of an ongoing cohort study of the Columbia Center for Children's Environmental Health (CCCEH), CBMCs and age 5 PBMCs were cultured with cockroach, mouse, and dust mite protein extracts. CBMC proliferation and cytokine (IL-5 and IFN-gamma) responses, and age 5 PBMC proliferation responses, were compared to anti-cockroach, anti-mouse, and anti-dust mite IgE levels, wheeze, cough, eczema and asthma.

RESULTS

Correlations between CBMC and age 5 PBMC proliferation in response to cockroach, mouse, and dust mite antigens were nonsignificant. Cockroach-, mouse-, and dust mite-induced CBMC proliferation and cytokine responses were not associated with allergen-specific IgE at ages 2, 3, and 5, or with asthma and eczema at age 5. However, after adjusting for potential confounders, age 5 cockroach-induced PBMC proliferation was associated with anti-cockroach IgE, total IgE, and asthma (p < 0.05).

CONCLUSION

In contrast to allergen-induced CBMC proliferation, age 5 cockroach-induced PBMC proliferation was associated with age 5 specific and total IgE, and asthma, in an inner-city cohort where cockroach allergens are prevalent and exposure can be high.

Gene-gene and gene-environment interactions on IgE production in prenatal stage

BACKGROUND

Prevalence of allergic diseases in children has increased worldwide over the past decades. Allergy sensitization may occur in fetal life. This study investigated whether gene-gene and gene-environment interactions affected cord blood IgE (CBIgE) levels.

METHODS

A total of 575 cord blood DNA samples were subjected to a multiplex microarray for 384 single nucleotide polymorphisms (SNPs) in 159 allergy candidate genes. Genetic association was initially assessed by univariate and multivariate analyses. Multifactor dimensionality reduction (MDR) was used to identify gene-gene and gene-environment interactions. Environmental factors for analysis included maternal atopy, paternal atopy, parental smoking, gender, and prematurity.

RESULTS

Twenty-one SNPs in 14 genes were associated with CBIgE elevation (>or =0.5 KU/l) in univariate analysis. Multivariate analysis identified eleven genes (IL13, IL17A, IL2RA, CCL17, CXCL1, PDGFRA, FGF1, HAVCR1, GNAQ, C11orf72, and ADAM33) which were significantly associated with CBIgE elevation. MDR analyses of gene-gene interactions identified IL13 interacted with IL17A and/or redox genes on CBIgE elevation with the prediction accuracy of 62.52%. Analyses of gene-environment interactions identified that maternal atopy combined with IL13, rs1800925 and CCL22, rs170359 SNPs had the highest prediction accuracy of 67.15%. All the high and low risk classifications on gene-gene and gene-environment interactions by MDR analyses could be validated by Chi-square test.

CONCLUSIONS

Gene-gene (e.g. immune and redox genes) and gene-environment (e.g. maternal atopy and FGF1or redox genes) interactions on IgE production begin in prenatal stage, suggesting that prevention of IgE-mediated diseases may be made possible by control of maternal atopy and redox responses in prenatal stage.

Birth order modifies the effect of IL13 gene polymorphisms on serum IgE at age 10 and skin prick test at ages 4, 10 and 18: a prospective birth cohort study

BACKGROUND

Susceptibility to atopy originates from effects of the environment on genes. Birth order has been identified as a risk factor for atopy and evidence for some candidate genes has been accumulated; however no study has yet assessed a birth order-gene interaction.

OBJECTIVE

To investigate the interaction of IL13 polymorphisms with birth order on allergic sensitization at ages 4, 10 and 18 years.

METHODS

Mother-infant dyads were recruited antenatally and followed prospectively to age 18 years. Questionnaire data (at birth, age 4, 10, 18); skin prick test (SPT) at ages 4, 10, 18; total serum IgE and specific inhalant screen at age 10; and genotyping for IL13 were collected. Three SNPs were selected from IL13: rs20541 (exon 4, nonsynonymous SNP), rs1800925 (promoter region) and rs2066960 (intron 1). Analysis included multivariable log-linear regression analyses using repeated measurements to estimate prevalence ratios (PRs).

RESULTS

Of the 1456 participants, birth order information was available for 83.2% (1212/1456); SPT was performed on 67.4% at age 4, 71.2% at age 10 and 58.0% at age 18. The prevalence of atopy (sensitization to one or more food or aeroallergens) increased from 19.7% at age 4, to 26.7% at 10 and 41.1% at age 18. Repeated measurement analysis indicated interaction between rs20541 and birth order on SPT. The stratified analyses demonstrated that the effect of IL13 on SPT was restricted only to first-born children (p = 0.007; adjusted PR = 1.35; 95%CI = 1.09, 1.69). Similar findings were noted for firstborns regarding elevated total serum IgE at age 10 (p = 0.007; PR = 1.73; 1.16, 2.57) and specific inhalant screen (p = 0.034; PR = 1.48; 1.03, 2.13).

CONCLUSIONS

This is the first study to show an interaction between birth order and IL13 polymorphisms on allergic sensitization. Future functional genetic research need to determine whether or not birth order is related to altered expression and methylation of the IL13 gene.

Maternal allergen immunisation to prevent sensitisation in offspring: Th2-polarising adjuvants are more efficient than a Th1-polarising adjuvant in mice

Background

Allergy has been an increasing problem in several parts of the world. Prenatal exposure to allergen and microbial components may affect the development of allergies in childhood, as indicated by epidemiological and experimental studies. We investigated the capacity for allergic sensitisation in offspring after induction of a Th1- or a Th2-polarised immune response to the same allergen in mothers during pregnancy.

Results

During pregnancy, mice were immunised with ovalbumin (OVA) given with either one of the Th2-adjuvants pertussis toxin (PT) or Al(OH)₃ (aluminium hydroxide), or with the Th1 adjuvant CpG. Offspring were immunised with OVA in Al(OH)₃ as young adults. Serum and supernatants from ex vivo stimulated or non-stimulated spleen cells from mothers and offspring were analysed for OVA-specific antibodies and cytokines, respectively. Mothers immunised with OVA together with either Al(OH)₃ or PT had increased levels of OVA-specific IgE and IgG1 compared to naive mothers, whereas mothers immunised with OVA together with CpG had increased levels of OVA-specific IgG2a compared to naive mothers. In general the highest levels of IL-5, IL-10, and IFNγ were observed in spleen cells from mothers immunised with PT and OVA. Upon immunisation, offspring from mothers immunised with OVA and either PT or Al(OH)₃ showed reduced levels of OVA-specific IgE and IgG1 and increased levels of OVA-specific IgG2a antibodies compared to offspring from naive mothers. Maternal immunisation with CpG and OVA did not affect antibody responses in offspring.

Conclusion

Allergic sensitisation in the offspring was affected by the type of adjuvant used for immunisation of the mothers with the same allergen. Th2 polarisation of the immune response in the mothers was found to give reduced IgE levels upon sensitisation of the offspring, whereas no reduction was achieved with Th1 polarisation in the mothers.

Elevated cord blood IgE is associated with recurrent wheeze and atopy at 7 yrs in a high risk cohort

There is considerable interest in identifying children at high risk for developing atopic diseases for primary prevention. This study evaluates risk factors for detectable cord blood IgE and assesses CB-IgE in predicting asthma and other IgE-mediated allergic diseases in children at high risk because of family history. Cord blood was obtained as part of a randomized controlled trial assessing the efficacy of an intervention program in the primary prevention of IgE-mediated allergic diseases. CB-IgE was measured and the degree to which this was associated with perinatal risk factors was assessed. The cohort was then evaluated for atopic disorders at 7 yrs of age to assess the predictive value of CB-IgE. Fifty-five (19.3%) of infants had detectable CB-IgE (>/=0.5 kU/l). Maternal atopy and birth in winter months were risk factors associated with detectable CB-IgE. CB-IgE was found to be significantly associated with allergic sensitization (OR 2.22; 95% CI 1.11, 4.41) and recurrent wheeze at 7 yrs (OR 2.51, 95% CI 1.09, 5.76) but not with other outcomes. CB-IgE may be a useful measure for identifying children at high risk of atopic diseases for the purpose of primary prevention.

Cord blood cytokines and chemokines and development of allergic disease

Exposure to ubiquitous allergens early in life, even before birth, may influence the incidence of allergic diseases later in life. During pregnancy, the fetomaternal interface is surrounded by high levels of T-helper (Th)2-like cytokines, possibly favouring the development of Th2-like immune responses in the offspring. The aim of this study was to evaluate the relation between cord blood (CB) IgE antibodies, Th1- and Th2-like cytokines and chemokines, maternal allergy and development of allergic disease during the first 2 yr of life in the offspring. The CB cytokine and chemokine levels from children of 20 allergic and 36 non-allergic women were determined by a multiplexed Luminex assay and ELISA. Total CB and maternal IgE antibody concentrations were quantified using ImmunoCAP technology. The maternal IgE levels during and after pregnancy correlated with CB IgE and Th2-associated macrophage-derived chemokine [MDC (CCL22)] levels. Development of allergic disease and sensitization was associated with increased CB IgE and MDC (CCL22) levels, as well as high ratios of MDC (CCL22) to Th1-associated interferon-gamma inducible protein 10 [IP-10 (CXCL10)] and interferon-gamma inducible T-cell alpha-chemoattractant [I-TAC (CXCL11) (n = 7 allergic vs. n = 25 non-allergic)]. The correlations between maternal IgE and CB IgE and MDC (CCL22) levels possibly indicate that the maternal immunity can affect the Th1/Th2 profile in the neonate. Development of allergic disease is associated with a more marked Th2-like deviation already at birth, shown as increased levels of CB IgE and MDC (CCL22) and higher ratios of MDC (CCL22) to IP-10 (CXCL10) and I-TAC (CXCL11).

Cord serum immunoglobulin E as a risk factor for allergic symptoms and sensitization in children and young adults

Early markers of atopic predisposition are needed for targeting allergy preventive measures to high-risk infants. An elevated cord serum immunoglobulin E (CS-IgE) level is considered a risk factor for subsequent allergy in childhood. However, the previous studies have not assessed the predictive value of CS-IgE in a follow-up extended to adulthood. We aimed at clarifying whether CS-IgE is useful in predicting subsequent atopic manifestations up to age 20 yr. A cohort of 200 unselected, full-term newborns were prospectively followed up from birth to age 20 yr. The CS-IgE level was successfully measured in 190 subjects at birth. The subjects were re-examined at ages of 5, 11 and 20 yr with assessment of the occurrence of allergic symptoms during the preceding year, skin prick testing and measurement of serum total IgE. An elevated CS-IgE level was associated with allergic symptoms and skin prick test positivity at age 5 yr (p = 0.03 and 0.01), with allergic rhinoconjunctivitis at age 20 yr (p = 0.04) and with an elevated serum total IgE at ages of 11 and 20 yr (p = 0.02 and 0.01). The sensitivity of CS-IgE, i.e. the probability of an elevated CS-IgE in an infant who subsequently develops atopy, in predicting skin prick test-verified atopy at ages of 5 and 20 yr was 50% and 26%, respectively. The combination of elevated CS-IgE and positive family history of allergy was strongly associated with subsequent atopic manifestations. Nevertheless, it showed a reduced sensitivity as compared to CS-IgE or family history of allergy. We conclude that an elevated CS-IgE level predicts subsequent atopy up to age 20 yr.

Cord blood allergen-specific IgE is associated with reduced IFN-gamma production by cord blood cells: the Protection against Allergy-Study in Rural Environments (PASTURE) Study

BACKGROUND

It is currently discussed whether allergic sensitization may start in utero under the influence of the maternal immune system and environmental determinants.

OBJECTIVE

To investigate the relationship between allergen-specific cord blood (CB) IgE levels, parental sensitization, CB cytokine production, and environmental influences.

METHODS

As part of an ongoing multicenter birth cohort study, allergen-specific IgE antibodies against 20 common seasonal, perennial, and food allergens were measured in blood samples from 922 neonates, 922 mothers, and 835 fathers. Supernatants from stimulated CB cells were assessed for the production of IL-5, IFN-gamma, IL-10, and TNF-alpha.

RESULTS

Allergen-specific IgE antibodies were detectable in 23.9% of newborns. Contamination with maternal serum was excluded by several means of analyses, including the absence of IgA antibodies. Clear correlation between maternal and fetal IgE was found only for hen's egg, cow's milk, and soybean allergen. Fetal IgE correlated negatively with the level of IFN-gamma production, but not with IL-5 and IL-10.

CONCLUSION

Allergen-specific IgE antibodies most probably of fetal origin are detectable in CB and correlate with a lowered CB IFN-gamma production.

The managed immune system: protecting the womb to delay the tomb

The developing immune system serves as a novel target for disruption by environmental chemicals and drugs, and one that can significantly influence later-life health risks. Specific immune maturational events occur during critical windows of pre- and early postnatal development that are not effectively modeled using adult exposure-assessment or general developmental toxicity screens. The range of postnatal health risks linked to developmental immunotoxicity (DIT) is influenced, in part, by the natural progression of prenatal-neonatal development. In this progression, the pregnancy itself imposes a Th2-bias in utero, and this produces a delay in the acquisition of Th1 functional capacity in the newborn. The status of Th1 regulatory and Th17 populations may also be important in immune function/dysfunction considerations. The necessary shift from a Th2 preferred capacity in late gestation to a more balance functional capacity in the neonate can be disrupted by xenobiotics leaving the child with increased vulnerability to a range of potential diseases. Knowledge of environmental factors that facilitate effective immune functional maturation as well as those xenobiotics capable of disrupting the process is important in strategies to reduce the incidence of diseases such as childhood asthma. Because hormesis has been shown to be an important factor in modulation of the adult immune system, it becomes even more important to understand potentially opposing dose-response effects for the immune system of the fetus, neonate, and juvenile. The direct linkage between immune dysfunction and chronic disease has become abundantly apparent in recent years. Therefore, a more comprehensive and effective approach for the protection of the developing immune system can help to reduce the incidence of later-life chronic diseases.

IL13 gene polymorphisms modify the effect of exposure to tobacco smoke on persistent wheeze and asthma in childhood, a longitudinal study

Background

Tobacco smoke and genetic susceptibility are risk factors for asthma and wheezing. The aim of this study was to investigate whether there is a combined effect of interleukin-13 gene (IL13) polymorphisms and tobacco smoke on persistent childhood wheezing and asthma.

Methods

In the Isle of Wight birth cohort (UK, 1989–1999), five IL13 single nucleotide polymorphisms (SNPs): rs1800925 (-1112C/T), rs2066960, rs1295686, rs20541 (R130Q) and rs1295685 were genotyped. Parents were asked whether their children had wheezed in the last 12 months at ages 1, 2, 4 and 10 years. Children who reported wheeze in the first 4 years of life and also had wheezing at age 10 were classified as early-onset persistent wheeze phenotype; non-wheezers never wheezed up to age 10. Persistent asthma was defined as having a diagnosis of asthma both during the first four years of life and at age 10. Logistic regression methods were used to analyze data on 791 children with complete information. Potential confounders were gender, birth weight, duration of breast feeding, and household cat or dog present during pregnancy.

Results

Maternal smoking during pregnancy was associated with early-onset persistent wheeze (OR 2.93, p < 0.0001); polymorphisms in IL13 were not (OR 1.15, p = 0.60 for the common haplotype pair). However, the effect of maternal smoking during pregnancy was stronger in children with the common IL13 haplotype pair compared to those without it (OR 5.58 and OR 1.29, respectively; p for interaction = 0.014). Single SNP analysis revealed a similar statistical significance for rs20541 (p for interaction = 0.02). Comparable results were observed for persistent childhood asthma (p for interaction = 0.03).

Conclusion

This is the first report that shows a combined effect of in utero exposure to smoking and IL13 on asthma phenotypes in childhood. The results emphasize that genetic studies need to take environmental exposures into account, since they may explain contradictory findings.

Environmental factors and allergic disorders

Despite numerous studies on possible associations between environmental exposure and allergic disorders, any conclusions made remain a matter of controversy. We conducted a review of evidence in relation to environmental and nutritional determinants and wheeze, asthma, atopic dermatitis, and allergic rhinitis. Identified were 263 articles for analysis after consideration of 1093 papers that were published since 2000 and selected by electronic search of the PubMed database using keywords relevant to epidemiological studies. Most were cross-sectional and case-control studies. Several prospective cohort studies revealed inconsistent associations between various environmental factors and the risk of any allergic disorder. Therefore, the evidence was inadequate to infer the presence or absence of a causal relationship between various environmental exposures and allergic diseases. However, evidence is suggestive of positive associations of allergies with heredity. Because almost all the studies were performed in Western countries, the application of these findings to people in other countries, including Japan, may not be appropriate. Further epidemiological information gained from population-based prospective cohort studies, in particular among Japanese together with other Asians, is needed to assess causal relationships between various environmental factors and allergic diseases.

Maternal allergy influences the proliferation of neonatal T cells expressing CCR4, CXCR5 or CD103

BACKGROUND

Elevated proliferative response to allergen in cord blood mononuclear cells (CBMCs) is related to subsequent allergy development of the neonate and has been suggested as a screening marker for high allergy risk.

OBJECTIVE

To characterize the proliferating cells in CBMCs from a neonatal group influenced by maternal allergy compared with a control group without known allergic heredity.

METHODS

CBMCs were stimulated with bovine beta-lactoglobulin (beta-LG) and proliferation was analysed by radioactive thymidine incorporation and expressed both as the traditional stimulation index (SI) and SI corrected by eliminating non-specific proliferation. After beta-LG combined with endotoxin stimulation, cellular expression of IL-4 and IFN-gamma mRNA was determined by quantitative RT-PCR and adhesion as well as chemokine receptors were analysed by three-colour flow cytometry in proliferating T cells (CD3+ Ki-67+).

RESULTS

The percentage of CCR4+ cells correlated weakly with concurrent IL-4 expression (r(S)=0.5, P<0.05), while CXCR3 correlated strongly with IFN-gamma expression (r(S)=0.83, P<0.001). In the allergy risk group, the percentage of proliferating T cells expressing CCR4 or integrin alphaE (CD103) was significantly reduced compared with the control group, while CXCR5 and the corrected SI were relatively increased (CCR4: P=0.01; integrin alphaE: P=0.03; CXCR5: P=0.04; SI: P=0.04).

CONCLUSION

Our results implied delayed maturation of immune functions involved in cellular migration, cell-cell interaction and immunoregulatory functions in neonates with hereditary allergy risk. The alterations observed in this subject group suggested that the corrected SI as well as proliferation of CCR4+, CXCR5+ or CD103+ T cells in allergen-stimulated CBMCs might serve as early screening markers for allergy risk.

IL13 gene polymorphism association with cord serum immunoglobulin E

Interleukin-13 (IL-13) has a pivotal role in the pathway of immunoglobulin E (IgE). Cord serum IgE has been suggested to be associated with allergy later in life, yet less affected by environmental exposures. We investigated the association of the interleukin-13 gene (IL13) polymorphisms on cord serum IgE. In the Isle of Wight birth cohort (UK, 1989-1990), cord serum IgE was measured using the ULTRA EIA kit and was dichotomized at 0.5 kU/l (n = 1358). Five single nucleotide polymorphisms (SNPs: rs1800925 in promoter, rs2066960 in intron 1, rs1295686 in intron 3, rs20541 in exon 4 and rs1295685 in exon 4) in IL13 were genotyped by pyrosequencing method. Linkage analysis using Haploview software revealed that rs1295686, rs20541 and rs1295685 were in strong linkage disequilibrium. Logistic regression and Armitage-Cochran test were used and gene association analysis included 798 children. Confounders were maternal age; maternal smoking, household dog, and household cat during pregnancy; season of birth; sex; position of child in family; and birth weight. SNP rs1295685 was associated with raised cord serum IgE (p = 0.031). This is the first report that shows an association between IL13 polymorphism and cord serum IgE.

Interaction of maternal atopy, CTLA-4 gene polymorphism and gender on antenatal immunoglobulin E production

BACKGROUND

Genetic heritability and maternal atopy have been correlated to antenatal IgE production, but very few studies have studied gene-maternal atopy interaction on antenatal IgE production. This study investigated the interaction of CTLA-4 polymorphism with prenatal factors on the elevation of cord blood IgE (CBIgE).

METHODS

Pregnant women were antenatally recruited for collection of prenatal environmental factors by a questionnaire. Umbilical cord blood samples were collected for CBIgE detection by fluorescence-linked enzyme assay and CTLA-4 polymorphism measurement by restriction fragment length polymorphism.

RESULTS

A total of 1104 pregnant women initially participated in this cohort study, and 898 of them completed cord blood collection. 21.4% of the newborns had elevation of CBIgE (>or=0.5 kU/L). The CTLA-4+49A allele (P=0.021), maternal atopy (P<0.001) and gender (P=0.034), but not the CTLA-4+49G allele, -318C allele, -318T allele, parental smoking or paternal atopy, were significantly correlated with the CBIgE elevation in multivariate analysis. A dichotomous analysis of gene-maternal atopy interactions identified maternal atopy and CTLA-4+49A allele had an additive effect on the CBIgE elevation, especially prominent in male newborns; and in the absence of maternal atopy, CTLA-4+49GG genotype had a protective effect on CBIgE elevation in female newborns.

CONCLUSIONS

Maternal but not paternal atopy has significant impacts on CBIgE elevation depending on gender and CTLA-4+49A/G polymorphism of newborns. Control of maternal atopy and modulation of CTLA-4 expression in the prenatal stage may be a target for the early prevention of perinatal allergy sensitization.

The predictive value of early life total immunoglobulin E measurement in identifying atopic children in a population-based birth cohort study

Atopy is common and the prevalence amongst children is rising. Measurements in early childhood that can predict subsequent development of atopy could be clinically useful for targeting preventive measures. We used the Children in Focus (CiF) subgroup of a large population-based birth cohort study (the Avon Longitudinal Study of Parents and Children) to investigate whether total immunoglobulin E (IgE) measured at 12 and 18 months could predict subsequent development of atopy at 5 yr of age. Atopy was determined by positive skin prick test (> or = 3 mm wheal) to one or more of 14 inhalant and food allergens. Prevalence of skin prick positivity to any allergen was 14.5% (104 of 715; 95% CI: 12.0-17.1%). Total IgE levels were significantly higher at 12 months of age (p < 0.0005) but not 18 months of age in those children subsequently atopic. The highest positive predictive value was 41% with an IgE measurement of >51 kU/l, with a sensitivity of 13.5% and a specificity of 95.8%. Although significant differences in early life IgE measurements were seen, the extent of overlap was great, such that the overall performance of IgE at 12 months as a screening test for atopy was poor.

Bioscience-bioethics and life factors affecting reproduction with special reference to the Indigenous Australian population

The demand for equality of recognition or respect is the dominant passion of modernity. The 20th century experienced a giant leap in technological inventiveness and ruthless use of technological power. In the 21st century, human welfare and environmental wellbeing demand fundamental political appraisal. We have the means, if we choose, to eradicate poverty and to responsibly protect the global environment. However, economic, political and cultural systems act to differentially allocate the benefits and risks for growth between socioeconomic groups. For example, it is a matter of pride that the neonatal mortality rate in affluent societies has dropped substantially since the late 1970s. However, the level of infant mortality (three times the national average) and low birthweight (13%) among the Indigenous Australian population is the highest in the country. With hindsight we now know that is the inevitable legacy of Australia’s colonial history. Chronic physical and psychological stress is recognized as an important etiological factor in many lifestyle diseases of the cardiovascular, immune and reproductive systems. Diseases of adaptation are further advanced by non-adaptive lifestyle choices, depression, alcoholism and other drug dependencies. This review describes the principles of bioscience ethics and targets equity issues as they affect human reproduction across generations with particular reference to the Indigenous population of Australia. The review also considers ways we may advance global and cultural maturity from the Indigenous Australian perspective and proposes an ecologically based model of preventative care. If we are to embrace fundamental social change and protect future children without threatening parents’ basic freedoms, then new beliefs and priorities – based on a compassionate understanding of biological systems – must evolve from the general public. Belief in human rights arising from a sense of human dignity is a collective outcome originating from individual commitment. The golden rule; that is, Nature’s principle of reciprocity, is fundamental in bridging the gap between knowledge and effective action.