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

Recent advances on diagnosis and management of childhood asthma and food allergies

The epidemic of childhood allergic disorders has been associated to the decline of infectious disease. However, exposure to many triggers (airborne viruses, tobacco smoke, pollution, indoor allergens, etc.) contribute to the disease. Breast feeding practices, nutrition, dietary and obesity also play a multifaceted role in shaping the observed worldwide trends of childhood allergies. Guidelines for treatment are available, but their implementation is suboptimal. Then developed countries are slowing learning integrating the development of suitable guidelines with implementation plans. Awareness, psychosocial and family factors strongly influence asthma and food allergy control. Moreover, monitoring tools are necessary to facilitate self-management. By taking into consideration these and many other pragmatic aspects, national public health programs to control the allergic epidemic have been successful in reducing its impact and trace the need for future research in the area.

Cord IgE and ECP levels of Malay neonates

BACKGROUND

Cord IgE and ECP levels are major atopic markers implicated in early childhood allergy development. Most epidemiological studies to date have not utilised current technology to establish baseline cord IgE levels, further aggravated by lack of data in this region. This study also attempts to identify a relationship between cord IgE and ECP levels as a mean to improve sensitivity for early prediction of atopy.

METHODS

A total of 3183 cord blood IgE including 44 cord ECP samples of term neonates from Malay parentage were recruited. Total IgE and ECP levels were determined by ImmunoCAP and fluoroimmunoenzymatic, respectively.

RESULTS

Cord IgE geometric mean was 0.15 kU/L. Males had higher IgE geometric mean than females (0.17 vs. 0.13). IgE values between 17 pair of twins was not significant (p=0.169). Frequency of males (29.9%) in >0.9 kU/L IgE category was higher than females (26.1%). In the <0.35 kU/L category, females had a higher frequency (44.8%) than males (39.1%). Males had significantly (p=0.023) higher IgE level than females. November and February had the highest mean and median cord IgE level whereas October and December were the lowest, respectively. IgE level across months was not significant (p=0.234). Cord ECP mean was 5.21 g/L and median was 3.75 μg/L. There was no significant correlation (p=0.513; r=-0.101) between cord blood ECP and IgE levels.

CONCLUSION

Cord blood IgE level of Malay male neonates was significantly higher than females. These results do not support cord ECP as plausible adjunct parameter to IgE for early atopic detection.

T cell subsets in cord blood are influenced by maternal allergy and associated with atopic dermatitis

BACKGROUND

This study aimed to investigate the influence of maternal allergy on cord blood regulatory and effector T cells and to evaluate their role as a predictor of atopic dermatitis (AD) during the first 2 yr of life.

METHODS

Seventy mother-infant pairs were recruited in this prospective birth cohort study (21 allergic and 49 non-allergic mothers). Cord blood samples were collected and assayed for the percentage of regulatory T cells (Treg), interferon-γ (IFN-γ), and interleukin-4 (IL-4) producing T cells (Th1 and Th2, respectively) using flow cytometry. Experiments were undertaken to assess the function of cord blood CD4(+) CD25(+) CD127(-) Treg cells by cell proliferation and cytokine responses. Their offspring at the age of 2 yr old were evaluated by dermatologists to determine whether they had AD.

RESULTS

During the first 2 yr of life, 15.7% of the children developed a physician-diagnosed AD. A significantly increased percentage of Th2 cell was observed in cord blood of newborns with maternal allergy. Treg/Th2 ratio significantly decreased among the offspring of allergic mothers. Treg cell-associated suppression of Th2 response was attenuated in Der p1-stimulated CD4(+) CD25(-) T cells from the offspring of allergic mothers. Children with reduced Th1/Th2 (p = 0.001, OR = 0.37) and Treg/Th2 (p = 0.001, OR = 0.47) ratio in cord blood had a higher risk of developing AD.

CONCLUSION

Maternal allergic status is associated with increased percentage of IL-4(+) CD4(+) T cells and a reduced Treg/Th2 ratio in cord blood at their children's birth, which may predispose to an increased risk for developing AD.

Atopic dermatitis 2.0: from the clinical phenotype to the molecular taxonomy and stratified medicine

Atopic dermatitis (AD) is a paradigmatic inflammatory chronic skin disease. As for other chronic skin diseases, (i) the spectrum of the clinical phenotype and severity as well as (ii) the genetic background and (iii) the underlying mechanisms strongly suggest a high degree of pathophysiological heterogeneity yet leading to a similar clinical pattern, that is, the eczematous skin lesion, but showing distinct progression patterns. This review suggests to exploit the recent knowledge about AD for a novel approach proposing a tentative first molecular taxonomy of this disease based on the genotype and endophenotype. The consequences in terms of personalized prevention and management are delineated.

IFN-λ and IgE-mediated allergic disease: a potential future role?

Reduced early microbial exposure has become a leading candidate to explain the rise in allergic disease, and research has focused on studying the interaction between the developing immune system and the microbial environment. However, despite intense interest, the pathways that lead to dysregulation of the immune system in allergic disease are still poorly understood. The newly described type III IFN-λ molecules were initially shown to exhibit antiviral activity, but these molecules are also likely to have an important role to play in the immune-epithelial interface, given their immunomodulatory functions and restricted receptor expression to immune and epithelial cells. Previous studies on the role of IFN-λ in allergic disease have been limited to allergic asthma. More recently, a genetic variation flanking IL28B encoding IFN-λ3 has been associated with allergic disease. Here, we examine this family and suggest how IFN-λ may be an important player in allergic disease.

Atopic dermatitis: a candidate for disease-modifying strategy

The concept of disease modification has been introduced to define the therapeutic strategies aimed to break, stop, or reverse the natural course of a chronic invalidating disease. This strategy is tightly related to the biomarker-based stratification of affected patients using genetic and other biological markers. With regard to the progress in understanding the genetic background of atopic dermatitis (AD), its natural history and its pivotal role in the emergence of allergic asthma, the time is mature to foster the research field of biomarkers in AD and to consider the elaboration of disease-modifying strategies in the management of AD with the goal to stop or even reverse the atopic march.

A review of psychosocial risk factors for pediatric atopy

Pediatric atopy is increasing in prevalence and creates a significant financial and quality of life burden for children and families (e.g., frequent clinic visits, academic, and social challenges). Thus, it is important to understand modifiable risk factors related to disease onset or exacerbation in young children. The existing research base suggests that while a genetic link has been identified, specific family psychological factors (e.g., parent stress) also appear to play a significant role in the development of pediatric atopy. The function of psychological stress in the clinical expression and exacerbation of allergic diseases in young children is hypothesized to be due to neuroendocrine and immunologic systems. Specifically, stress-related activation of the sympathetic and adrenomedullary (SAM) system as well as the hypothalamic-pituitary-adrenocortical (HPA) axis from both the intrauterine environment and early childhood experiences may increase risk of childhood atopy above and beyond genetic risk. Consequently, prevention and intervention strategies aimed at reducing children's early exposure to stress and psychological difficulties in parents may prove beneficial in preventing or reducing the likelihood that their children will develop atopy.