Effect of polymorphisms on TGFB1 on allergic asthma and helminth infection in an African admixed population

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2017-05-10T16:51:01Z No. of bitstreams: 1 Costa RS Effect of polymorphisms....pdf: 397845 bytes, checksum: 0d9be39ccd3aab2517c962ca6a35d75d (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2017-05-10T18:42:15Z (GMT) No. of bitstreams: 1 Costa RS Effect of polymorphisms....pdf: 397845 bytes, checksum: 0d9be39ccd3aab2517c962ca6a35d75d (MD5)Made available in DSpace on 2017-05-10T18:42:15Z (GMT). No. of bitstreams: 1 Costa RS Effect of polymorphisms....pdf: 397845 bytes, checksum: 0d9be39ccd3aab2517c962ca6a35d75d (MD5) Previous issue date: 2017Wellcome Trust, the HCPC Latin America Excellence Centre Programme (072405/Z/03/Z), and the Brazilian agency Conselho Nacional de Desenvolvimento Científico e TecnológicoeCNPqJohns Hopkins University. Division of Allergy and Clinical Immunology. Baltimore, Maryland / Federal University of Bahia. Health Science Institute. Salvador, BA, BrazilFederal University of Bahia. Health Science Institute. Salvador, BA, BrazilFederal University of Bahia. Public Health Institute. Salvador, BA, Brazil / Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil / Fundação Oswaldo Cruz. Rio de Janeiro, RJ, BrazilFederal University of Bahia. Health Science Institute. Salvador, BA, BrazilLondon School of Hygiene and Tropical Medicine. London, EnglandFederal University of Bahia. Center of Excellence in Asthma. Salvador, BA, BrazilJohns Hopkins University. Division of Allergy and Clinical Immunology. Baltimore, MarylandJohns Hopkins University. Division of Allergy and Clinical Immunology. Baltimore, MarylandJohns Hopkins University. Division of Allergy and Clinical Immunology. Baltimore, MarylandJohns Hopkins University. Division of Allergy and Clinical Immunology. Baltimore, MarylandJohns Hopkins University. Division of Allergy and Clinical Immunology. Baltimore, MarylandJohns Hopkins University. Division of Allergy and Clinical Immunology. Baltimore, MarylandJohns Hopkins University. Division of Allergy and Clinical Immunology. Baltimore, Maryland / University of Colorado Denver. Department of Medicine. Aurora, ColoradoAllergic asthma is a complex disorder that results from a combination of genetic and environmental factors. Studies suggest that helminth infections can activate a regulatory network characterized by the production of regulatory cytokines, such as interleukin 10 and transforming growth factor β1 (TGF-β1) and subsequently protect against immune-mediated diseases, such as asthma. On the other hand, TGF-β1 is increased in the lungs of individuals with asthma and may modulate airway inflammation. The role of TGF- β 1 single-nucleotide polymorphisms (SNPs) in allergic disease remains inconclusive. Objective: To evaluate the effects of genetic variations in the TGF-b1 on allergy and helminths infections in children. Methods: We tested for association among 4 TGF-b1 SNPs and allergic asthma, specific IgE, skin prick test result, and IL-10 production in 1,335 Brazilians. In addition, we analyzed the association with markers of helminth infection (parasite burden, anti-Ascaris IgE, and worm specific IgG4). The polymorphisms were genotyped using Taq Man probes. Results: We found an association between rs1800470 (C allele) and atopic wheezing (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.37e0.95) and markers of allergy (OR, 0.41; 95% CI, 0.22e0.79). In contrast, a positive association was observed between the haplotype ACCA and Trichuris trichiura infection (OR, 1.85; P ¼ .003) and Ascaris lumbricoides infection (OR, 2.01; P < .001). This haplotype was also associated with increased IL-10 production (b ¼ 50.7; P < .001). Conclusion: Individuals with TGF-b1 polymorphisms have an increased susceptibility to helminth infections and a lower risk of developing allergy. These studies suggest that immune modulation of allergic disease results not only from environmental factors but also from genetic susceptibility and IL-10 productio

Targeted deep sequencing identifies rare loss-of-function variants in IFNGR1 for risk of atopic dermatitis complicated by eczema herpeticum

BackgroundA subset of atopic dermatitis is associated with increased susceptibility to eczema herpeticum (ADEH+). We previously reported that common single nucleotide polymorphisms (SNPs) in the IFN-γ (IFNG) and IFN-γ receptor 1 (IFNGR1) genes were associated with the ADEH+ phenotype.ObjectiveWe sought to interrogate the role of rare variants in interferon pathway genes for the risk of ADEH+.MethodsWe performed targeted sequencing of interferon pathway genes (IFNG, IFNGR1, IFNAR1, and IL12RB1) in 228 European American patients with AD selected according to their eczema herpeticum status, and severity was measured by using the Eczema Area and Severity Index. Replication genotyping was performed in independent samples of 219 European American and 333 African American subjects. Functional investigation of loss-of-function variants was conducted by using site-directed mutagenesis.ResultsWe identified 494 single nucleotide variants encompassing 105 kb of sequence, including 145 common, 349 (70.6%) rare (minor allele frequency &lt;5%), and 86 (17.4%) novel variants, of which 2.8% were coding synonymous, 93.3% were noncoding (64.6% intronic), and 3.8% were missense. We identified 6 rare IFNGR1 missense variants, including 3 damaging variants (Val14Met [V14M], Val61Ile, and Tyr397Cys [Y397C]) conferring a higher risk for ADEH+ (P = .031). Variants V14M and Y397C were confirmed to be deleterious, leading to partial IFNGR1 deficiency. Seven common IFNGR1 SNPs, along with common protective haplotypes (2-7 SNPs), conferred a reduced risk of ADEH+ (P = .015-.002 and P = .0015-.0004, respectively), and both SNP and haplotype associations were replicated in an independent African American sample (P = .004-.0001 and P = .001-.0001, respectively).ConclusionOur results provide evidence that both genetic variants in the gene encoding IFNGR1 are implicated in susceptibility to the ADEH+ phenotype

Allelic association of <i>IL13</i> SNPs with chronic and late-stage <i>S</i>. <i>japonicum infection</i>.

<p>Allelic association of <i>IL13</i> SNPs with chronic and late-stage <i>S</i>. <i>japonicum infection</i>.</p

An IL-13 Promoter Polymorphism Associated with Liver Fibrosis in Patients with <i>Schistosoma japonicum</i>

<div><p>The aim of this study was to determine whether two polymorphisms in the gene encoding <i>IL13</i> previously associated with <i>Schistosoma hematobium</i> (<i>S</i>. <i>hematobium</i>) and <i>S</i>. <i>mansoni</i> infection are associated with <i>S</i>. <i>japonicum</i> infection. Single nucleotide polymorphisms (SNPs) rs1800925 (IL13/-1112C>T) and rs20541 (IL13R130Q) were genotyped in 947 unrelated individuals (307 chronically infected, 339 late-stage with liver fibrosis, 301 uninfected controls) from a schistosomiasis-endemic area of Hubei province in China. Regression models were used to evaluate allelic and haplotypic associations with chronic and late-stage schistosomiasis adjusted for non-genetic covariates. Expression of IL-13 was measured in <i>S</i>. <i>japonicun</i>-infected liver fibrosis tissue and normal liver tissue from uninfected controls by immunohistochemistry (IHC). The role of rs1800925 in IL-13 transcription was further determined by Luciferase report assay using the recombinant PGL4.17-rs180092 plasmid. We found SNP rs1800925T was associated with late-stage schistosomiasis caused by <i>S</i>. <i>japonicum</i> but not chronic schistosomiasis (OR = 1.39, 95%CI = 1.02–1.91, p = 0.03) and uninfected controls (OR = 1.49, 95%CI = 1.03–2.13, p = 0.03). Moreover, the haplotype rs1800925T-rs20541C increased the risk of disease progression to late-stage schistosomiasis (OR = 1.46, p = 0.035), whereas haplotype rs1800925C-rs20541A showed a protective role against development of late-stage schistosomiasis (F = 0.188, OR = 0.61, p = 0.002). Furthermore, <i>S</i>. <i>japonicum</i>-induced fibrotic liver tissue had higher IL13 expression than normal liver tissue. Plasmid PGL4.17-rs1800925T showed a stronger relative luciferase activity than Plasmid PGL4.17-rs1800925C in 293FT, QSG-7701 and HL-7702 cell lines. In conclusion, the functional <i>IL13</i> polymorphism, rs1800925T, previously associated with risk of schistosomiasis, also contributes to risk of late-stage schistosomiasis caused by <i>S</i>. <i>japonicum</i>.</p></div

Haplotypic association of <i>IL13</i> SNPs with chronic and late-stage <i>S</i>. <i>japonicum</i> infection.

<p>F1, frequency of controls; F2, frequency of chronic cases; F3, frequency of late-stage cases.</p><p>Haplotypic association of <i>IL13</i> SNPs with chronic and late-stage <i>S</i>. <i>japonicum</i> infection.</p

IL-13 protein was determined by IHC and western blot.

<p>(A) Representative images of normal liver tissues and <i>S</i>.<i>japonicum</i>-induced fibrotic liver tissues (Images were captured at 100x and 400x with scale bar of 100 μm). (B) Comparison of scores of ST2 staining intensity betwee <i>S</i>. <i>japonicum</i>-induced fibrotic liver tissues and normal liver tissues. (C) IL-13 protein was detected in liver tissue lysates by western blots.</p

General characteristics of <i>IL13</i> SNPs in Chines study samples.

<p>* From hg19.</p><p>General characteristics of <i>IL13</i> SNPs in Chines study samples.</p

Whole genome sequencing identifies novel genetic mutations in patients with eczema herpeticum

BackgroundEczema herpeticum (EH) is a rare complication of atopic dermatitis (AD) caused by disseminated herpes simplex virus (HSV) infection. The role of rare and/or deleterious genetic variants in disease etiology is largely unknown. This study aimed to identify genes that harbor damaging genetic variants associated with HSV infection in AD with a history of recurrent eczema herpeticum (ADEH+).MethodsWhole genome sequencing (WGS) was performed on 49 recurrent ADEH+ (≥3 EH episodes), 491 AD without a history of eczema herpeticum (ADEH-) and 237 non-atopic control (NA) subjects. Variants were annotated, and a gene-based approach (SKAT-O) was used to identify genes harboring damaging genetic variants associated with ADEH+. Genes identified through WGS were studied for effects on HSV responses and keratinocyte differentiation.ResultsEight genes were identified in the comparison of recurrent ADEH+to ADEH-and NA subjects: SIDT2, CLEC7A, GSTZ1, TPSG1, SP110, RBBP8NL, TRIM15, and FRMD3. Silencing SIDT2 and RBBP8NL in normal human primary keratinocytes (NHPKs) led to significantly increased HSV-1 replication. SIDT2-silenced NHPKs had decreased gene expression of IFNk and IL1b in response to HSV-1 infection. RBBP8NL-silenced NHPKs had decreased gene expression of IFNk, but increased IL1b. Additionally, silencing SIDT2 and RBBP8NL also inhibited gene expression of keratinocyte differentiation markers keratin 10 (KRT10) and loricrin (LOR).ConclusionSIDT2 and RBBP8NL participate in keratinocyte's response to HSV-1 infection. SIDT2 and RBBP8NL also regulate expression of keratinocyte differentiation genes of KRT10 and LOR

Relative luciferase activity of plasmid construct of PGL4.17-rs1800925T and PGL4.17-rs1800925C in 293FT, QSG-7701 and HL-7702 cell lines.

<p>(A) Complementary base sequence of target DNA in plasmid PGL4.17-rs1800925C. (B) Complementary base sequence of target DNA in plasmid PGL4.17-rs1800925T constructed by overlap PCR. (C) Relative luciferase activity of plasmid construct of PGL4.17-rs1800925T and PGL4.17-rs1800925C in 293FT, QSG-7701 and HL-7702 cell lines. (Rs1800925C indicates plasmid PGL4.17-rs1800925C and rs1800925T indicates plasmid PGL4.17-rs1800925T).</p