The association ofGM-CSF-677A/C promoter gene polymorphism with the occurrence and severity of atopic dermatitis in a Polish population

Association of IL-4 and IL-18 genetic polymorphisms with atopic dermatitis in Chinese children

Background

Atopic dermatitis (AD) is a common chronic inflammatory skin disease, adversely affecting nearly 20% of the pediatric population worldwide. Interleukin-4 (IL-4) and interleukin-18 (IL-18) are considered to be involved in the pathogenesis and development of AD. The aim of this study was to investigate the association of IL-4 and IL-18 gene polymorphisms with the susceptibility and severity of AD in Chinese children.

Methods

Six candidate single nucleotide polymorphisms (SNPs) in IL-4 and IL-18 genes were genotyped through multi-PCR combined with next-generation sequencing in 132 AD children and 100 healthy controls, and all the analyses were performed on blood genome DNA.

Results

The frequencies of G allele, CG genotype and CG + GG genotype of IL-4 rs2243283, as well as the haplotype IL-4/GTT (rs2243283-rs2243250-rs2243248) were all significantly decreased in AD patients compared with the controls [G vs. C: P = 0.033, OR = 0.59; CG vs. CC: P = 0.024, OR = 0.47; CG + GG vs. CC: P = 0.012, OR = 0.49; GTT vs. CCT: P = 0.011, OR = 0.65]. Moreover, the frequencies of A allele, AA genotype and AG + AA genotype of IL-18 rs7106524, along with the haplotype IL-18/CAA (rs187238-rs360718-rs7106524) were statistically increased in the severe AD patients (A vs. G: P < 0.001, OR = 2.79; AA vs. GG: P = 0.003, OR = 5.51; AG + AA vs. GG: P = 0.036, OR = 2.93; CAA vs. CAG: P = 0.001, OR = 2.86).

Conclusions

Our findings suggested that genetic variation in IL-4 rs2243283 such as G allele, CG genotype and CG + GG genotype might confer the reduced susceptibility to AD in Chinese children. Furthermore, A allele, AA genotype and AG + AA genotype of IL-18 rs7106524 explored the strong association with severity in Chinese AD children.

Pharmacogenomics of Monoclonal Antibodies for the Treatment of Rheumatoid Arthritis

Precision medicine refers to a highly individualized and personalized approach to patient care. Pharmacogenomics is the study of how an individual’s genomic profile affects their drug response, enabling stable and effective drug selection, minimizing side effects, and maximizing therapeutic efficacy. Rheumatoid arthritis (RA) is an autoimmune disease that causes chronic inflammation in the joints. It mainly starts in peripheral joints, such as the hands and feet, and progresses to large joints, which causes joint deformation and bone damage due to inflammation of the synovial membrane. Here, we review various pharmacogenetic studies investigating the association between clinical response to monoclonal antibody therapy and their target genetic polymorphisms. Numerous papers have reported that some single nucleotide polymorphisms (SNPs) are related to the therapeutic response of several monoclonal antibody drugs including adalimumab, infliximab, rituximab, and tocilizumab, which target tumor necrosis factor (TNF), CD20 of B-cells, and interleukin (IL)-6. Additionally, there are some pharmacogenomic studies reporting on the association between the clinical response of monoclonal antibodies having various mechanisms, such as IL-1, IL-17, IL-23, granulocyte-macrophage colony-stimulating factor (GM-CSF) and the receptor activator of nuclear factor-kappa B (RANK) inhibition. Biological therapies are currently prescribed on a “trial and error” basis for RA patients. If appropriate drug treatment is not started early, joints may deform, and long-term treatment outcomes may worsen. Pharmacogenomic approaches that predict therapeutic responses for RA patients have the potential to significantly improve patient quality of life and reduce treatment costs.

TLR4 polymorphisms as potential predictors of atopic dermatitis in Chinese Han children

Background

Toll‐like receptor 4 (TLR4) is considered to be involved in the pathogenesis and progression of atopic dermatitis (AD). In the present study, we evaluated the relationship between TLR4 gene polymorphisms and the susceptibility or severity of AD among Chinese Han children.

Methods

A total of 132 AD patients and 100 healthy controls were enrolled in this study. Four single‐nucleotide polymorphisms (rs19277914, rs11536891, rs7869402, and rs11536889) of the TLR4 gene were genotyped by multiplex PCR combined with next‐generation sequencing.

Results

Our results showed that a significantly reduced risk for AD was associated with C allele [p = 0.008; odds ratio (OR) = 0.41, C vs. T], TC genotype (p = 0.022; OR = 0.41, TC vs. TT), and TC + CC genotype (p = 0.010; OR = 0.39, TC + CC vs. TT) of TLR4 rs11536891. The frequency of the haplotype GCCG (rs1927914–rs11536891–rs7869402–rs11536889) in AD patients was lower than that in the controls (p = 0.010; OR = 0.38). Moreover, the results indicated that a higher risk of severe AD was related to the T allele (p = 0.019; OR = 2.97, T vs. C) and the TC genotype (p = 0.021; OR = 3.34, TC vs. CC) of TLR4 rs7869402. A risk haplotype of TLR4 (GTTG) was found in severe AD patients (p = 0.010; OR = 5.26).

Conclusions

Our data suggested that TLR4 rs11536891 polymorphism was associated with the susceptibility to AD in Chinese Han children. And TLR4 rs7869402 might confer the severity of pediatric AD patients.

Genetic and Epigenetic Aspects of Atopic Dermatitis

Atopic dermatitis is a heterogeneous disease, in which the pathogenesis is associated with mutations in genes encoding epidermal structural proteins, barrier enzymes, and their inhibitors; the role of genes regulating innate and adaptive immune responses and environmental factors inducing the disease is also noted. Recent studies point to the key role of epigenetic changes in the development of the disease. Epigenetic modifications are mainly mediated by DNA methylation, histone acetylation, and the action of specific non-coding RNAs. It has been documented that the profile of epigenetic changes in patients with atopic dermatitis (AD) differs from that observed in healthy people. This applies to the genes affecting the regulation of immune response and inflammatory processes, e.g., both affecting Th1 bias and promoting Th2 responses and the genes of innate immunity, as well as those encoding the structural proteins of the epidermis. Understanding of the epigenetic alterations is therefore pivotal to both create new molecular classifications of atopic dermatitis and to enable the development of personalized treatment strategies.

Replicated methylation changes associated with eczema herpeticum and allergic response

Background

Although epigenetic mechanisms are important risk factors for allergic disease, few studies have evaluated DNA methylation differences associated with atopic dermatitis (AD), and none has focused on AD with eczema herpeticum (ADEH+). We will determine how methylation varies in AD individuals with/without EH and associated traits. We modeled differences in genome-wide DNA methylation in whole blood cells from 90 ADEH+, 83 ADEH−, and 84 non-atopic, healthy control subjects, replicating in 36 ADEH+, 53 ADEH−, and 55 non-atopic healthy control subjects. We adjusted for cell-type composition in our models and used genome-wide and candidate-gene approaches.

Results

We replicated one CpG which was significantly differentially methylated by severity, with suggestive replication at four others showing differential methylation by phenotype or severity. Not adjusting for eosinophil content, we identified 490 significantly differentially methylated CpGs (ADEH+ vs healthy controls, genome-wide). Many of these associated with severity measures, especially eosinophil count (431/490 sites).

Conclusions

We identified a CpG in IL4 associated with serum tIgE levels, supporting a role for Th2 immune mediating mechanisms in AD. Changes in eosinophil level, a measure of disease severity, are associated with methylation changes, providing a potential mechanism for phenotypic changes in immune response-related traits.

Electronic supplementary material

The online version of this article (10.1186/s13148-019-0714-1) contains supplementary material, which is available to authorized users.

Allergies - A T cells perspective in the era beyond the TH1/TH2 paradigm

Allergic diseases have emerged as a major health care burden, especially in the western hemisphere. They are defined by overshooting reactions of an aberrant immune system to harmless exogenous stimuli. The T_H1/T_H2 paradigm assumes that a dominance of T_H2 cell activation and an inadequate T_H1 cell response are responsible for the development of allergies. However, the characterization of additional T helper cell subpopulations such as T_H9, T_H17, T_H22, T_HGM-CSF and their interplay with regulatory T cells suggest further layers of complexity. This review summarizes state-of-the-art knowledge on T cell diversity and their induction, while revisiting the T_H1/T_H2 paradigm. With respect to these numerous contributors, it offers a new perspective on the pathogenesis of asthma, allergic rhinitis (AR) and atopic dermatitis (AD) incorporating recent discoveries in the field of T cell plasticity.