The role of IL10 and IL17 gene polymorphisms in treatment response in children and adolescents with severe asthma.

OBJECTIVE: To determine whether polymorphisms of the IL10 and IL17 genes are associated with severe asthma control and bronchodilator reversibility in children and adolescents with severe asthma. METHODS: This was a cross-sectional study, nested within a prospective cohort study of patients with severe asthma. Two outcomes were evaluated: asthma control and bronchodilator reversibility. We extracted DNA from peripheral blood and genotyped three single nucleotide polymorphisms: rs3819024 and rs2275913 in the IL17A gene; and rs3024498 in the IL10 gene. For the association analyses, we performed logistic regression in three genetic models (allelic, additive, and dominant). RESULTS: The rs3024498 C allele in the IL10 gene was associated with failure to achieve asthma control despite regular treatment (p = 0.02). However, the G allele of the IL17A rs3819024 polymorphism was associated with failure to respond to stimulation with a b2 agonist. The rs2275913 polymorphism of the IL17A gene showed no relationship with asthma control or bronchodilator reversibility. CONCLUSIONS: In pediatric patients with severe asthma, the IL10 polymorphism appears to be associated with failure to achieve clinical control, whereas the IL17A polymorphism appears to be associated with a worse bronchodilator response. Knowledge of the involvement of these polymorphisms opens future directions for pharmacogenetic studies and for the implementation of individualized therapeutic management of severe asthma in pediatric patients.

MTOR gene variants are associated with severe COVID-19 outcomes: A multicenter study.

BACKGROUND: The worst outcomes linked to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been attributed to the cytokine storm, which contributes significantly to the immunopathogenesis of the disease. The mammalian target of rapamycin (mTOR) pathway is essential for orchestrating innate immune cell defense including cytokine production and is dysregulated in severe Coronavirus Disease 2019 (COVID-19) individuals. The individual genetic background might play a role in the exacerbated immune response. OBJECTIVE: In this study, we aimed to investigate the association between MTOR genetic variants and COVID-19 outcomes. METHODS: This study enrolled groups of individuals with severe (n = 285) and mild (n = 207) COVID-19 from Brazilian states. The MTOR variants, rs1057079 and rs2536, were genotyped. A logistic regression analysis and Kaplan-Meier survival curves were performed. We applied a genotyping risk score to estimate the cumulative contribution of the risk alleles. Tumor necrosis factor (TNF) and interleukin-6 (IL-6) plasma levels were also measured. RESULTS: The T allele of the MTOR rs1057079 variant was associated with a higher likelihood of developing the most severe form of COVID-19. In addition, higher levels of IL-6 and COVID-19 death was linked to the T allele of the rs2536 variant. These variants exhibited a cumulative risk when inherited collectively. CONCLUSIONS: These results show a potential pathogenetic role of MTOR gene variants and may be useful for predicting severe outcomes following COVID-19 infection, resulting in a more effective allocation of health resources.

Genetic variants associated with SARS-CoV-2 infection also affect lung function and asthma severity.

Background: Host genetic factors may be associated with COVID-19 unfavourable outcomes. The first genome-wide association study (GWAS) conducted in individuals with respiratory failure due to COVID-19 revealed susceptibility loci close to six genes (SLC6A20, LZTFL1, CCR9, FYCO1, CXCR6 and XCR1) and the ABO blood-group gene. We aimed to investigate how polymorphisms in those genes could relate to lung function and severe asthma in a Brazilian population. Methods: DNA samples of 784 individuals following the ProAR (Programa para Controle da Asma e Rinite Alérgica da Bahia) were genotyped by the Multi-Ethnic Global Array panel with ∼2 million polymorphisms (Illumina). Polymorphisms in SLC6A20, LZTFL1, CCR9, FYCO1, CXCR6, XCR1 and the ABO blood-group gene were evaluated. Logistic regression for severe asthma, airway obstruction and lack of FEV1 reversibility was performed using PLINK software 1.9, in the additive model and was adjusted for sex, age and PCA-1. Pairwise Linkage disequilibrium analyses were performed using Haploview 4.2. The haplotypes and gene score analyses were performed in the SNPstat tool. In silico functions of polymorphisms were analysed using rSNPbase and RegulomeDB plataforms. Results: We identified the rs8176733 (G allele) and rs8176725 (A allele) in the ABO blood-group gene as risk factors for severe asthma, lower pulmonary obstruction and lack of FEV1 reversibility. Polymorphisms in CCR9 are risk factors for both severe asthma (A allele of rs34338823) and airway obstruction (A allele of rs6806802). The markers rs13079478 (A allele) and rs75817942 (A allele) in FYCO1 are related to more severe asthma and a lack of FEV1 reversibility, respectively. We identified the A allele of both rs35731912 and rs34338823 in LZTFL1 as risk factors for severe asthma. The marker rs6806802 (C allele) was associated with airway obstruction and rs7614952 (A allele), rs7625839 (G allele) and rs112509260 (A allele) are related to a lack of FEV1 reversibility. The A allele of rs2531747 in the SLC6A20 gene is also associated with severe asthma. Conversely, polymorphisms in XCR1 play a protective role in relation to severe asthma (A allele of rs2036295) and airway obstruction (A allele of rs2036295). Additionally, we found that individuals with a higher number of risk alleles have a greater risk of severe asthma, airway obstruction and FEV1 reversibility. Conclusion: Our study suggests that polymorphisms in genes associated with respiratory failure in SARS-CoV-2-infected individuals are associated with greater susceptibility to severe asthma and reduced lung function in subjects with asthma.

PDE4D gene variants and haplotypes are associated with asthma and atopy in Brazilian children.

PDE4D (Phosphodiesterase 4D) gene encodes a hydrolase of cyclic AMP. PDE4D genetic variants have been associated with asthma susceptibility. Therefore, this study aimed to investigate the association between PDE4D variants (and haplotypes) with asthma and atopy in a Brazilian population. The study comprised 1,246 unrelated participants from the SCAALA (Social Changes Asthma and Allergy in Latin America) program. Genotyping was performed using the Illumina 2.5 Human Omni bead chip. Multivariate logistic regression was used to investigate the association between PDE4D variants and asthma/atopy phenotypes in PLINK 1.09 software. Twenty-four SNVs in PDE4D were associated with atopy or asthma. The rs6898082 (A) variant increased asthma susceptibility (OR 2.76; CI 99% 1.26-6.03) and was also related to a greater PDE4D expression in the GTEx database. Also, the variant rs6870632 was further associated with asthma in meta-analysis with a replication cohort. In addition, the variants rs75699812 (C), rs8007656 (G), and rs958851 (T) were positively associated with atopy. Moreover, these variants formed an atopy risk haplotype (OR 1.82; CI 99% 1.15-2.88). Also, these variants were related to lower levels of IL-10. Functional in silico assessment showed that some PDE4D SNVs may have an impact on gene regulation and expression. Variants in the PDE4D are positively associated with asthma and allergy markers. It is possible that these variants lead to alteration in PDE4D expression and therefore impact immunity and pulmonary function.

Genetic polymorphism (rs6587666) in FLG protects from eczema in admixed Brazilian children population with high African ancestry.

Genetic variants in filaggrin (FLG) are key in eczema and are less common in Africans than in Europeans and Asians. Here we examined the association between FLG Single Nucleotide Polymorphisms (SNPs) and eczema in a population of admixed Brazilian children and whether African ancestry modifies this association. We included 1010 controls and 137 cases and ran logistic regressions between SNPs in FLG and eczema in the studied population and also stratified the analyses according to the degree of African ancestry. In addition, we tested the replication of the findings on an independent set of individuals, as well as, we verified the impact on FLG expression according to each SNP genotype. The T allele of SNP rs6587666 was negatively associated with eczema in additive model (OR: 0.66, 95% CI: 0.47-0.93, P: 0.017). Moreover, African ancestry modifies the association between rs6587666 and eczema. The effect of the T allele was higher among individuals with higher African ancestry and the association with eczema was lost in individuals with lower African ancestry. In our analyses the expression of FLG in skin was slightly downregulated by the presence of the T allele of rs6587666. In our population, the T allele of rs6587666 in FLG was associated with protection to eczema and the degree of African ancestry was able to modify the observed association.

The role of IL10 and IL17 gene polymorphisms in treatment response in children and adolescents with severe asthma / O papel de polimorfismos dos genes IL10 e IL17 na resposta ao tratamento em crianças e adolescentes com asma grave

ABSTRACT Objective: To determine whether polymorphisms of the IL10 and IL17 genes are associated with severe asthma control and bronchodilator reversibility in children and adolescents with severe asthma. Methods: This was a cross-sectional study, nested within a prospective cohort study of patients with severe asthma. Two outcomes were evaluated: asthma control and bronchodilator reversibility. We extracted DNA from peripheral blood and genotyped three single nucleotide polymorphisms: rs3819024 and rs2275913 in the IL17A gene; and rs3024498 in the IL10 gene. For the association analyses, we performed logistic regression in three genetic models (allelic, additive, and dominant). Results: The rs3024498 C allele in the IL10 gene was associated with failure to achieve asthma control despite regular treatment (p = 0.02). However, the G allele of the IL17A rs3819024 polymorphism was associated with failure to respond to stimulation with a b2 agonist. The rs2275913 polymorphism of the IL17A gene showed no relationship with asthma control or bronchodilator reversibility. Conclusions: In pediatric patients with severe asthma, the IL10 polymorphism appears to be associated with failure to achieve clinical control, whereas the IL17A polymorphism appears to be associated with a worse bronchodilator response. Knowledge of the involvement of these polymorphisms opens future directions for pharmacogenetic studies and for the implementation of individualized therapeutic management of severe asthma in pediatric patients.

RESUMO Objetivo: Determinar se existe relação entre polimorfismos dos genes IL10 e IL17 e controle da asma grave e reversibilidade com broncodilatador em crianças e adolescentes com asma grave. Métodos: Estudo transversal, aninhado em um estudo prospectivo de coorte com pacientes com asma grave. Foram avaliados dois desfechos: controle da asma e reversibilidade com broncodilatador. Extraímos DNA do sangue periférico e genotipamos três polimorfismos de nucleotídeo único: rs3819024 e rs2275913 no gene IL17A e rs3024498 no gene IL10. Para as análises de associação, realizamos regressão logística em três modelos genéticos (alélico, aditivo e dominante). Resultados: O alelo C do polimorfismo rs3024498 do gene IL10 apresentou relação com asma que permaneceu descontrolada mesmo com tratamento regular (p = 0,02). No entanto, o alelo G do polimorfismo rs3819024 do gene IL17A apresentou relação com ausência de resposta ao estímulo com b2-agonista. O polimorfismo rs2275913 do gene IL17A não apresentou relação com controle da asma ou reversibilidade com broncodilatador. Conclusões: Em pacientes pediátricos com asma grave, o polimorfismo do gene IL10 parece estar relacionado com ausência de controle clínico, ao passo que o polimorfismo do gene IL17A parece estar relacionado com pior resposta ao broncodilatador. O conhecimento a respeito do envolvimento desses polimorfismos abre perspectivas futuras para estudos farmacogenéticos e para a implantação de manejo terapêutico individualizado da asma grave em pacientes pediátricos.

Frequência alélica e potencial regulatório de polimorfismosno gene NELL1 em uma população da Bahia ­ Brasil / Allele frequency and regulatory potential of polimorphisms in NELL1 gene in a population of Bahia ­ Brazil

Introdução: o gene NELL1 codifica a proteína semelhante ao fator de crescimento epidérmico (do inglês Epidermal Growth factor (EGF)-like). GWASs e estudos de associação com genes candidatos têm sido utilizados para estabelecer a conexão entre polimorfismos de nucleotídeo único (SNP) no NELL1 e diversas doenças. Objetivo: descrever a frequência alélica e o potencial regulatório dos polimorfismos do gene NELL1, estudados em uma população de Salvador (Bahia, Brasil) e descrever a frequência desses polimorfismos e a associação com diversas doenças, em populações africana, ameríndia, asiática e europeia. Metodologia: 1094 participantes foram recrutados através do Programa de Controle da Asma e da Rinite Alérgica no Estado da Bahia (ProAR). Os indivíduos tiveram o DNA genômico extraído e genotipado, utilizando-se a plataforma Illumina. Os SNP foram consultados através da plataforma SeattleSec Annotation. As bases de dados NCBI, RegulomeDB e Haploview 4.2 foram utilizadas para as análises. Resultados: foram analisados 346 SNPs do gene NELL1. Desses, 53 SNPs tiveram o MAF variando entre 50% e 40% e função intrônica. Os SNPs rs10833465 (alelo A), rs908944 (alelo C), rs1516766 (alelo A), rs10766739 (alelo G) e rs11025878 (alelo G) apresentam uma pontuação de 3, de acordo com o banco do RegulomeDB. O SNP rs7117671, com pontuação 2b, pode ter impacto regulatório e funcional. 101 SNPs apresentaram o MAF entre 39% e 20%. Dos polimorfismos menos frequentes nessa população, 192 apresentaram um MAF entre 19% e 2%. Discussão: alguns SNPs, com diferentes frequências, apresentaram alta probabilidade de impacto funcional. Foram encontrados, na literatura, estudos de associação dos SNPs e osteoporose, doenças metabólicas, condições inflamatórias, doenças neuropsiquiátricas e tumores malignos. Conclusão: ospolimorfismos do gene NELL1 estudados apresentaram diferentes frequências na população desse estudo e tiveram seus alelos associados a doenças em diferentes populações. Sugere-se que sejam realizados mais estudos.

Introduction: the NELL1 gene encodes the epidermal growth factor (EGF)-like protein. GWASs and association studies with candidate genes have been used to establish the connection between single nucleotide polymorphisms (SNP) in NELL1 and various diseases. Objective: to describe the allele frequency and regulatory potential of NELL1 gene polymorphisms studied in a population from Salvador, Bahia, Brazil; and to describe the frequency of these polymorphisms, and the association with various diseases, in African, Amerindian, Asian and European populations. Methodology: one thousand and ninety-four (1094) participants were recruited through the Program for the Control of Asthma and Allergic Rhinitis in the State of Bahia (ProAR). Individuals had their genomic DNA extracted and genotyped using the Illumina platform. The SNPs were consulted through the SeattleSec Annotation platform. The NCBI, RegulomeDB and Haploview 4.2 databases were used for the analyses. Results: four hundred and seventy-three (346) NELL1 gene SNPs were analyzed. Of these, 53 SNPs had MAF ranging between 50% and 40% and intronic function. The SNPs rs10833465 (A allele), rs908944 (C allele), rs1516766 (A allele), rs10766739 (G allele) and rs11025878 (G allele) showed a score of 3, according to the RegulomeDB database. SNP rs7117671, with score 2b, may have regulatory and functional impact. One hundred and eighteen (101) SNPs presented MAF between 39% and 20%. Of the less frequent polymorphisms in this population, 192 had a MAF between 19% and 2%. Discussion: some SNPs, with different frequencies, presented a high probability of functional impact. Studies on the association of SNPs and osteoporosis, metabolic diseases, inflammatory conditions, neuropsychiatric diseases and malignant tumors were found in the literature. Conclusion: the NELL1 gene polymorphisms studied showed different frequencies in the population of this study and had their alleles associated with diseases in different populations. It is suggested that further studies be carried out.

Effects of GRIN2B , GRIA1 , and BDNF Polymorphisms on the Therapeutic Action of Ketamine and Esketamine in Treatment-Resistant Depression Patients: Secondary Analysis From a Randomized Clinical Trial.

OBJECTIVE: This study aimed to evaluate the effect of genetic variants in glutamate ionotropic receptor N-methyl- d -aspartate type subunit 2B ( GRIN2B ), glutamate ionotropic receptor α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid type subunit 1 ( GRIA1 ), and brain-derived neurotrophic factor ( BDNF ) genes on therapeutic response, remission, and total Montgomery-Åsberg Depression Rating Scale scores after treatment with ketamine or esketamine in treatment-resistant depression (TRD) patients. METHODS: Participants (N = 60) are from a double-blind, randomized, noninferiority clinical trial comparing single-dose intravenous ketamine (0.5 mg/kg) to esketamine (0.25 mg/kg) for TRD. Montgomery-Åsberg Depression Rating Scale was applied at baseline, 24 hours, 72 hours, and 7 days postinfusion to assess depressive symptoms. Blood samples were collected to evaluate single nucleotide polymorphisms rs1805502 ( GRIN2B ), rs1994862 ( GRIA1 ), and rs6265 ( BDNF ). RESULTS: There was no association between rs1805502, rs1994862, or rs6265 polymorphisms and antidepressant response ( P = 0.909, P = 0.776, and P = 0.482, respectively), remission P = 0.790, P = 0.086, and P = 0.669), or Montgomery-Åsberg Depression Rating Scale scores at each time point ( P = 0.907, P = 0.552, and P = 0.778). CONCLUSIONS: We found no association between the studied single nucleotide polymorphisms (rs6265, rs1805502, and rs1994862) and ketamine's therapeutic action in TRD patients. Further studies with larger samples are needed to clarify the utility of these genes of interest as predictors for antidepressant treatment.

Impact of FOXP3 gene polymorphisms and gene-environment interactions in asthma and atopy in a Brazilian population.

BACKGROUND: Polymorphisms in genes related to the activation and development of regulatory T cells (Tregs), such as FOXP3, may be associated with asthma and atopy development. Additionally, environmental factors such as exposure to infections can modify the effect of these associations. This study evaluated the impact of polymorphisms in the FOXP3 on the risk of asthma and atopy as also gene-environment interactions in these outcomes. METHODS: This study included 1,246 children from the SCAALA program, between 4 and 11 years of age. DNA was extracted from peripheral blood and eight SNPs (rs2280883, rs11465476, rs11465472, rs2232368, rs3761549, rs3761548, rs2232365 and rs2294021) were genotyped using the 2.5 HumanOmni Beadchip from Illumina (San Diego, California, USA) or TaqMan qRT-PCR. RESULTS: The rs2232368 (Allele T) was positively associated with asthma symptoms (OR = 1.95, CI = 1.04 to 3.66, p = 0.040) and skin prick test (SPT) reactivity to aeroallergens (OR = 2.31, CI = 1.16 to 4.59, p = 0.017). The rs3761549 (Allele T) was positively associated with SPT reactivity (OR = 1.44, CI = 1.03 to 2.02, p = 0.034). The rs2280883 (Allele C) was negatively associated with specific IgE to aeroallergens (OR = 0.83, CI = 0.70 to 0.99, p = 0.040). Furthermore, the rs2280883 played a protective role in the development of atopy only in individuals seropositive to Epstein-Barr virus (EBV) infection (OR = 0.74, CI = 0.60 to 0.92, p = 0.003 and OR = 0.74; 95% CI = 0.61-0.91, p = 0.007 for SPT and slgE respectively), but not in individuals without EBV infection. CONCLUSION: Polymorphisms in the FOXP3 gene were associated with the risk of atopy and asthma development in our population. In addition, EBV infection had an effect modifier of the observed association for rs2280883 variant.

Variants in proinflammatory genes IL1RL1, IL1B and IRF4 are associated with overweight in a pediatric Brazilian population.

BACKGROUND: Obesity is a chronic complex disease with great prevalence for children all over the world. Characterized for low-grade inflammation associated with several comorbidities such as resistance and type 2 diabetes mellitus (T2DM). OBJECTIVES: To investigate whether genetic variants in IL10, IL1RL1, IL1B, IRF4, TNF, IL6, and IL33 genes are associated with being overweight in children. METHODS: We performed the genotyping of 1004 children using Illumina 2.5 Human Omni bead chip, and association analysis on the genetic variants and the overweight through logistic regression adjusted for sex, age and components principal. RESULTS: Of the seven genes analyzed, 16 SNVs significantly associated. Eleven variants in IL1RL1, two in IL1B and one in IRF4 genes increased overweight risk and two SNVs in IL1RL1 were associated with protection against overweight. The rs2287047-A was negatively associated (OR: 0.66, CI95%: 0.19-0.45) and had a reduced IL1RL1 expression in whole blood (p 0.033) in silico eQTL. The rs12203592-T, in IRF4, was positively associated with being overweight, and led to an increased gene expression in whole blood (p < 0.001) and adipose tissue (p < 0.001). CONCLUSION: These results suggest that genetic variants in inflammatory genes may play an important role in the development of overweight in children.

Heterozygote Advantage of the Type II Deiodinase Thr92Ala Polymorphism on Intrahospital Mortality of COVID-19.

CONTEXT: The type 2 deiodinase and its Thr92Ala-DIO2 polymorphism have been linked to clinical outcomes in acute lung injury and pulmonary fibrosis. OBJECTIVE: Our objectives were to evaluate were cumulative mortality during admission according to Thr92Ala-DIO2 polymorphism. METHODS: Here we conducted an observational, longitudinal, and prospective cohort study to investigate a possible association between the Thr92Ala-DIO2 polymorphism and intrahospital mortality from COVID-19 in adult patients admitted between June and August 2020. Blood biochemistry, thyroid function tests, length of stay, comorbidities, complications, and severity scores were also studied according to Thr92Ala-DIO2 polymorphism. RESULTS: In total, 220 consecutive patients (median age 62; 48-74 years) were stratified into 3 subgroups: Thr/Thr (n = 79), Thr/Ala (n = 119), and Ala/Ala (n = 23). While the overall mortality was 17.3%, the lethality was lower in Ala/Thr patients (12.6%) than in Thr/Thr patients (21.7%) or Ala/Ala patients (23%). The heterozygous genotype (Thr/Ala) was associated with a 47% reduced risk of intrahospital mortality whereas univariate and multivariate logistic regression adjusted for multiple covariates revealed a reduction that ranged from 51% to 66%. The association of the Thr/Ala genotype with better clinical outcomes was confirmed in a metanalysis of 5 studies, including the present one. CONCLUSION: Here we provide evidence for a protective role played by Thr92Ala-DIO2 heterozygosity in patients with COVID-19. This protective effect follows an inheritance model known as overdominance, in which the phenotype of the heterozygote lies outside the phenotypical range of both homozygous.

Caracterização de polimorfismos nos genes OPG, RANK e RANKL em uma população brasileira / Characterization of OPG, RANK and RANKL gene polymorphisms in a Brazilian population

Introdução: o sistema RANKL (receptor-ativador do fator nuclear-ligante κB)/RANK (receptor ativador do NF-kB)/OPG (osteoprotegrina) Introdução: o sistema OPG (osteoprotegrina)/RANK (receptor ativador do NF-kB)/RANKL (receptor-ativador do fator nuclear-ligante κB) regula os processos fisiológicos e patológicos da remodelação óssea. Polimorfismos genéticos nos genes OPG, RANK e RANKL têm sido associados a doenças, em diferentes populações. Objetivo: Descrever a frequência e o potencial regulatório dos polimorfismos do sistema OPG, RANK e RANKL em uma população brasileira; avaliar o seu potencial como marcadores genéticos informativos de ancestralidade; comparar com patologias associadas em outras populações. Metodologia: neste estudo, 506 indivíduos adultos, participantes de uma coorte acometidos de asma e periodontite, tiveram o DNA genômico extraído e genotipado, utilizando-se a plataforma Illumina. As plataformas NCBI, RegulomeDB, Haploview 4.2 e rSNPBase foram consultadas e utilizadas para análises. Resultados e Discussão: os polimorfismos mais frequentes na população estudada foram o rs3102724 no gene OPG, com frequência de menor alelo (MAF) de 46%; o rs4941129 em RANK, MAF 50%; e o rs9525641 em RANKL, MAF 46%. Os rs3134063 (1f) em OPG, rs17069898 (1f) em RANK e rs2200287 (1d) em RANKL apresentaram maior impacto funcional. Em OPG e RANK, nove polimorfismos se caracterizaram como marcadores genéticos informativos de ancestralidade, com predomínio nas populações YRI (africanos) e CEU (europeus). Os nove polimorfismos, com função intrônica, apresentaram MAF entre 2 a 46% na população-alvo e foram associados a patologias do metabolismo ósseo em outras populações. Conclusão: polimorfismos dos genes estudados se mostraram frequentes na população estudada e tiveram seus alelos mais frequentes associados a doenças em populações ancestrais. Sugere-se que sejam realizados mais estudos.

Introduction: The OPG (osteoprotegerin)/ RANK (NF-kB activating receptor)/ RANKL (nuclear-binding factor κB receptor-activating system regulates the physiological and pathological processes of bone remodeling. Genetic polymorphisms (SNPs) in OPG, RANK and RANKL genes have been associated with diseases in different populations. Objective: Describe the regulatory frequency and potential of SNPs in OPG, RANK and RANKL in a Brazilian population; assess their potential as informative genetic markers of ancestry; compare with pathologies associated with these polymorphisms in other populations. Methods: in this study, 506 adult individuals, participating in a cohort involving asthma and periodontitis, had genomic DNA extracted and genotyped using the Illumina platform. The NCBI, RegulomeDB, Haploview 4.2 and rSNPBase platforms were consulted and used for analysis. Results and discussion: the most frequent polymorphisms in the studied population were the rs3102724 in the OPG gene, with the lowest allele frequency (MAF) of 46%; rs4941129 in RANK, MAF 50% and rs9525641 in RANKL, MAF 46%. The rs3134063 (1f) in OPG, rs17069898 (1f) in RANK and rs2200287 (1d) in RANKL, had greater functional impact. In OPG and RANK, 9 SNPs were characterized as informative genetic markers of ancestry, predominantly in YRI (African) and CEU (European) populations. These 9 SNPs, with intronic function, presented MAF between 2 and 46% in our population, and were associated with pathologies in bone metabolism in other populations. Conclusion: SNPs of the studied genes were found to be frequent in the studied population and had their most frequent alleles associated with diseases in ancestral populations. It is suggested that further studies be carried out

S-methyl cysteine sulfoxide mitigates histopathological damage, alleviate oxidative stress and promotes immunomodulation in diabetic rats.

OBJECTIVES: S-methyl cysteine sulfoxide (SMCS) is a hydrophilic cysteine-containing natural compound found in plants and is known to possess antidiabetic and antioxidant properties. We investigated the antioxidant and immunomodulatory properties of SMCS, as well as histopathological changes in the liver and pancreas in streptozotocin (STZ)-induced diabetic rats. METHODS: The rats were divided into the following groups: control (CG), comprising non-diabetic rats; STZ-DB, comprising STZ-induced diabetic rats; and STZ-SMCS, comprising STZ-induced diabetic rats treated with SMCS. SMCS (200 mg/kg) was administered by gavage daily for 30 days. Biochemical and cytokine analyses, catalase (CAT) and superoxide dismutase (SOD) activities assays and histopathological analysis of liver and pancreas tissues were performed. RESULTS: SMCS treatment reduced glycemia (p<0.05), decreased triglyceride (p<0.01) and very-low-density lipoprotein (VLDL) levels (p<0.01), and increased SOD and CAT activity in the liver (both p<0.01) compared with STZ-DB group. Higher activity values of IL-10 were observed in the STZ-SMCS group than in the other groups (p<0.001). Liver glycogen was significantly improved in the STZ-SMCS group compared with the STZ-DB group. SMCS also ameliorated damage to pancreatic islets, which resulted in restoration of their morphology. CONCLUSIONS: Oral treatment of SMCS showed improvement of the morphological alterations in liver and pancreatic islet in diabetic rats. These beneficial morphological effects of SMCS can be partially explained by IL-10 modulation associated with antioxidant action.

WSB1 and IL21R Genetic Variants Are Involved in Th2 Immune Responses to Ascaris lumbricoides.

Genetic and epigenetic factors are considered to be critical for host-parasite interactions. There are limited data on the role of such factors during human infections with Ascaris lumbricoides. Here, we describe the potential role of genetic factors as determinants of the Th2 immune response to A. lumbricoides in Brazilian children. Stool samples were collected from the children to detect A. lumbricoides by microscopy and peripheral blood leukocytes (PBLs) were cultured in whole blood cultures for detection of cytokines (IL-5, IL-10, and IL-13) in vitro. Levels of anti-A. lumbricoides IgE and IgG4 were measured in plasma. DNA was extracted from PBLs and genotyped using Illumina 2.5 Human Omni Beadchip. Candidate genes associated with A. lumbricoides responses were identified and SNVs in these selected genes associated with the Th2 immune response to A. lumbricoides. Haplotype, gene expression, and epigenetic analyses were done to identify potential associations with Th2 immune responses. GWAS on samples from 1,189 children identified WSB1 as a candidate gene, and IL-21R was selected as a biologically relevant linked gene for further analysis. Variants in WSB1 and IL21R were associated with markers of Th2 immune responses: increased A. lumbricoides-specific IgE and IL-5/IL-13 by PBLs from infected compared to uninfected individuals. In infected children, WSB1 but not IL21R gene expression was suppressed and increased methylation was observed in the WSB1 promoter region. This is the first study to show an association between genetic variants in WSB1 and IL21R and Th2 immune responses during A. lumbricoides infections in children. WSB1/IL21R pathways could provide a potential target for the treatment of Th2-mediated diseases.

Understanding Asthma and Allergies by the Lens of Biodiversity and Epigenetic Changes.

Exposure to different organisms (bacteria, mold, virus, protozoan, helminths, among others) can induce epigenetic changes affecting the modulation of immune responses and consequently increasing the susceptibility to inflammatory diseases. Epigenomic regulatory features are highly affected during embryonic development and are responsible for the expression or repression of different genes associated with cell development and targeting/conducting immune responses. The well-known, "window of opportunity" that includes maternal and post-natal environmental exposures, which include maternal infections, microbiota, diet, drugs, and pollutant exposures are of fundamental importance to immune modulation and these events are almost always accompanied by epigenetic changes. Recently, it has been shown that these alterations could be involved in both risk and protection of allergic diseases through mechanisms, such as DNA methylation and histone modifications, which can enhance Th2 responses and maintain memory Th2 cells or decrease Treg cells differentiation. In addition, epigenetic changes may differ according to the microbial agent involved and may even influence different asthma or allergy phenotypes. In this review, we discuss how exposure to different organisms, including bacteria, viruses, and helminths can lead to epigenetic modulations and how this correlates with allergic diseases considering different genetic backgrounds of several ancestral populations.

Genetic polymorphisms in vitamin D pathway influence 25(OH)D levels and are associated with atopy and asthma.

BACKGROUND: Vitamin D deficiency or insufficiency, has been associated with atopy and lack of asthma control. Our objective was to investigate associations between variants in genes of vitamin D pathway with serum levels of 25-hydroxyvitamin D (25(OH)D), atopy, asthma and asthma severity in teenagers from Northeast Brazil. METHODS: This is a cross sectional study nested in a cohort population of asthma. 25(OH)D was quantified from 968 of 11-17 years old individuals by ELISA. Asthma diagnosis was obtained by using the ISAAC Phase III questionnaire. Specific IgE was determined by ImmunoCAP; genotyping was performed using the 2.5 HumanOmni Biochip from Illumina. Statistical analyses were performed in PLINK 1.07 and SPSS 22.1. RESULTS: After quality control, 104 Single Nucleotides Variants (SNVs) in vitamin D pathway genes, typed in 792 individuals, were included in the analysis. The allele A of rs10875694 on VDR was positively associated with atopy (OR = 1.35; 95% CI 1.01-1.81). The allele C of rs9279 on VDR, was negatively associated with asthma risk (OR = 0.66; 95% CI 0.45-0.97), vitamin D insufficiency (OR = 0.78; 95% CI 0.70-0.96) and higher VDR expression. Two variants in VDR were associated with asthma severity, the allele A of rs2189480 (OR = 0.34; 95% CI 0.13-0.89) and the allele G of rs4328262 (OR = 3.18; 95% CI 1.09-9.28). The combination of variants in CYP2R1 and CYP24A1 (GAC, to rs10500804, rs12794714 and rs3886163, respectively) was negatively associated with vitamin D production (ß = - 1.24; 95% CI - 2.42 to - 0.06). CONCLUSIONS: Genetic variants in the vitamin D pathway affect vitamin D serum levels and, thus, atopy and asthma.

New Challenge for Zika Virus Infection: Human Reservoirs?

Zika virus (ZIKV) is considered to cause an acute self-limited infection in adults, and microcephaly in fetus. Presence of the virus for long periods has been detected in body fluids; however, persistent viremia in serum for more than 1 year has not yet been reported. We have investigated persistence of ZIKV in serum samples of 77 subjects who were infected by the virus between 18 months and 3 years before the start of this study. The subjects included children with microcephaly and their parents. Serum samples were subjected to routine RT-qPCR assay for ZIKV, Chikungunya virus, and Dengue virus. From the 77 subjects, five showed positive for the presence of ZIKV particles by RT-qPCR, including four members of the same family. Viral isolation in Vero cells and C6/36 cells confirmed the result and showed the viral particles were active. We have detected viremia in healthy carriers up to 3 years after symptom onset. Humans acting as potential viral reservoirs have major implication for the current understanding of ZIKV infection.

Genetic variants in 17q12-21 locus and childhood asthma in Brazil: Interaction with Varicella zoster virus seropositivity.

BACKGROUND: Asthma is a complex disease with worldwide public health relevance, is related to environmental causes and a genetic predisposition. The chromosomal 17q12-21 locus has been consistently demonstrated to be associated with asthma risk. The effects of variants in the 17q12-21 locus on childhood asthma were first identified in a genome wide- association study. Since that time, those findings have been replicated in different populations but not in South American populations. OBJECTIVE: This study aimed to investigate the role of variants in the 17q12-21 locus on asthma in a sample of Brazilian children. METHODS: This was a cross-sectional study conducted on a cohort of 1247 children. These analyses used 50 Single Nucleotide Variants (SNVs) in the 17q12-21 locus were genotyped as part of a genome wide association study (GWAS). RESULTS: Four SNVs (rs4065275, rs12603332, rs73985228 and rs77777702) were associated with childhood asthma. The rs73985228 exhibited the strongest association across the different genetic models (OR, 95%CI 2.8, 1.44-3.21, p < 0.01). In an analysis that was stratified by atopy, two SNVs (rs73985228 and rs2715555) were found to be associated with atopic and non-atopic asthma. For the first time, we observed a significant interaction with seropositivity for the Varicella zoster virus (for rs4065275, p = 0.02, and for rs12603332, p = 0.04); i.e., the association was found in those who were seropositive but not in those who were seronegative for this virus. CONCLUSIONS: We confirmed the associations of variants in the 17q12-21 locus with atopic and non-atopic asthma and identified an interaction with seropositivity for the Varicella zoster virus.

Variants in the IL17 pathway genes are associated with atopic asthma and atopy makers in a South American population.

BACKGROUND: Asthma is a complex disorder with multiple phenotypes which can influence its severity and response to treatment. The TH17 lymphocytes producing IL-17A and IL17-F cytokines, may have a role on asthma inflammation. The aim of our study was to evaluate the association between genetic variants in IL17 pathway genes with asthma and atopy markers. MATERIALS AND METHODS: Genotyping was performed using a commercial panel in 1245 participants of SCAALA cohort. The study included 91 SNVs in IL-17 pathway genes. Logistic regressions for asthma and atopy markers were performed using PLINK 1.9. In silico analyses were performed using rSNPbase, RegulomeDB, and Gtex portal for in silico gene expression. RESULTS AND DISCUSSION: The T allele of rs1974226 in IL17A was positively associated with asthma (OR: 1.37; 95% CI 1.02-1.82). Also, the T allele of rs279548 was positively associated with asthma (OR: 1.30; 95% CI 1.02-1.64), atopy (OR: 1.62; 95% CI 1.05-2.50) and increased expression of the IL17RC in lung and whole blood tissues. The others genetic variants in the IL17 pathways genes were associated with both protection and risk for asthma development as well as with IgE levels. CONCLUSION: The genetic variants in IL-17-related genes are associated with the atopic asthma phenotype and IgE production.