The role of IL-22 produced by Th17 cells in Type 1 Diabetes

Interleukin-22 (IL-22) is produced by T helper 17 (Th17) cells. Th17 cells have been shown to be pathogenic in autoimmune diseases, however their role in type 1 diabetes (T1D) remains controversial. We have shown that Th17-differentiation of naïve T cells can be driven by IL-23 + IL-6 to produce large amounts of IL-22 and induce T1D. Conversely, polarizing T cells using TGF-β + IL-6 led to nonpathogenic Th17 cells that produced lower IL-22 levels. We have shown that neutralizing IFN-γ during polarization leads to a drastic increase in IL-22. We have also found IL-22-producing cells in the pancreas of diabetic NOD mice. The receptor for IL-22 increases in the pancreas of NOD mice during disease providing a target for IL-22. However, neutralization of IL-22 by antibody in vivo does not significantly alter disease progression. Therefore, IL-22 may not be the sole factor or play a non-redundant role in T1D pathogenesis

The involvement of interleukin-22 in the expression of pancreatic beta cell regenerative Reg genes

Background: In Type 1 diabetes, the insulin-producing β-cells within the pancreatic islets of Langerhans are destroyed. We showed previously that immunotherapy with Bacillus Calmette-Guerin (BCG) or complete Freund’s adjuvant (CFA) of non-obese diabetic (NOD) mice can prevent disease process and pancreatic β-cell loss. This was associated with increased islet Regenerating (Reg) genes expression, and elevated IL-22-producing Th17 T-cells in the pancreas. Results: We hypothesized that IL-22 was responsible for the increased Reg gene expression in the pancreas. We therefore quantified the Reg1, Reg2, and Reg3δ (INGAP) mRNA expression in isolated pre-diabetic NOD islets treated with IL-22. We measured IL-22, and IL-22 receptor(R)-α mRNA expression in the pancreas and spleen of pre-diabetic and diabetic NOD mice. Our results showed: 1) Reg1 and Reg2 mRNA abundance to be significantly increased in IL-22-treated islets in vitro; 2) IL-22 mRNA expression in the pre-diabetic mouse pancreas increased with time following CFA treatment; 3) a reduced expression of IL-22Rα following CFA treatment; 4) a down-regulation in Reg1 and Reg2 mRNA expression in the pancreas of pre-diabetic mice injected with an IL-22 neutralizing antibody; and 5) an increased islet β- cell DNA synthesis in vitro in the presence of IL-22. Conclusions: We conclude that IL-22 may contribute to the regeneration of β-cells by up-regulating Regenerating Reg1 and Reg2 genes in the islets

Inflammatory endotype of odontogenic sinusitis

BACKGROUND: Odontogenic sinusitis (ODS) is distinct from non-odontogenic rhinosinusitis with regard to clinical features as well as diagnostic and therapeutic approaches. While numerous studies have explored immune profiles of chronic rhinosinusitis, very few studies have explored the inflammatory endotype of ODS. METHODS: Odontogenic sinusitis was diagnosed by confirming infectious sinusitis adjacent to infectious maxillary odontogenic pathology. Maxillary sinus cultures and mucosal biopsies were obtained during endoscopic endonasal surgery in ODS and control patients. Controls were patients undergoing endoscopic skull base surgery with no sinus disease. Specimens were snap frozen in liquid nitrogen and stored at -80°C. Analysis was performed using a multiplex assay to measure Th-1 (TNFα, IFNγ, IL-2,12,18), Th-2 (IL-4,5,9,13), Th-17 (IL-17A,17F,22), and innate (CCL5,CXCL9,CXCL10, IL-6,8,10,12,23,27) immune pathways. Groups were compared via independent sample t-tests; if assumptions were violated, nonparametric Wilcoxon ranked sum tests were performed. RESULTS: Specimens from 22 ODS patients were compared to nine controls. ODS mucosal tissue was sampled in the setting of the following dental pathologies: post-dental extraction (n = 15), untreated apical periodontitis (n = 2), apical periodontitis after root canal therapy (n = 2), and maxillary sinus bone grafting with or without dental implantation (n = 3). The following cytokines were significantly elevated in ODS compared to controls: IFNγ, TNFα, IL-6, 8, 10, 27, and CXCL9. IL-17 levels were similar in both ODS and controls. Therefore, ODS demonstrated heightened innate and Th1 immune activity. CONCLUSION: ODS demonstrated both innate immune and Th1 inflammatory endotypes. Further studies are needed to explore ODS immunopathobiology and its potential impact on ODS management

Characterization of basophils in infants in the microbes, allergy, asthma and Pets (MAAP) birth cohort

RATIONALE: Basophils are mature circulating granulocytic cells that play an important role in IgE-dependent immune responses. The objective of this study was to prospectively examine, in very early life, basophils for FcϵRIa and activation markers, which are involved in a Th2 response. METHODS: Cord blood and venous blood at 6 months of age were obtained from 65 infants enrolled in the MAAP (Microbes, Allergy, Asthma and Pets) birth cohort. Basophil percentages were determined by manual differential count of 200 cells in whole blood smears. The enriched granulocyte fraction collected after Ficoll separation of peripheral blood mononuclear cells was examined by flow cytometry. Basophils were defined as low side scatter/Class II 2/CD123+ cells. Cells expressing FcϵRIa or the activation markers CD203c or CD63 were examined and were reported as % of basophils expressing these markers. Paired t-tests were used to assess change over time. RESULTS: Basophils represented a mean 0.78% (range 0 to 2.5%) and 0.88% (range 0 to 4.0%) of the differential among cord and 6 month blood samples, respectively. There was a statistically significant increase from birth to 6 months of age in the proportion of basophils expressing FcϵRIa (mean increase 12.7%, p=0.007), CD203c (mean increase 16.7%,

Expression quantitative trait locus fine mapping of the 17q12–21 asthma locus in African American children: a genetic association and gene expression study

BackgroundAfrican ancestry is associated with a higher prevalence and greater severity of asthma than European ancestries, yet genetic studies of the most common locus associated with childhood-onset asthma, 17q12-21, in African Americans have been inconclusive. The aim of this study was to leverage both the phenotyping of the Children's Respiratory and Environmental Workgroup (CREW) birth cohort consortium, and the reduced linkage disequilibrium in African Americans, to fine map the 17q12-21 locus.MethodsWe first did a genetic association study and meta-analysis using 17q12-21 tag single-nucleotide polymorphisms (SNPs) for childhood-onset asthma in 1613 European American and 870 African American children from the CREW consortium. Nine tag SNPs were selected based on linkage disequilibrium patterns at 17q12-21 and their association with asthma, considering the effect allele under an additive model (0, 1, or 2 effect alleles). Results were meta-analysed with publicly available summary data from the EVE consortium (on 4303 European American and 3034 African American individuals) for seven of the nine SNPs of interest. Subsequently, we tested for expression quantitative trait loci (eQTLs) among the SNPs associated with childhood-onset asthma and the expression of 17q12-21 genes in resting peripheral blood mononuclear cells (PBMCs) from 85 African American CREW children and in upper airway epithelial cells from 246 African American CREW children; and in lower airway epithelial cells from 44 European American and 72 African American adults from a case-control study of asthma genetic risk in Chicago (IL, USA).Findings17q12-21 SNPs were broadly associated with asthma in European Americans. Only two SNPs (rs2305480 in gasdermin-B [GSDMB] and rs8076131 in ORMDL sphingolipid biosynthesis regulator 3 [ORMDL3]) were associated with asthma in African Americans, at a Bonferroni-corrected threshold of p<0·0055 (for rs2305480_G, odds ratio [OR] 1·36 [95% CI 1·12-1·65], p=0·0014; and for rs8076131_A, OR 1·37 [1·13-1·67], p=0·0010). In upper airway epithelial cells from African American children, genotype at rs2305480 was the most significant eQTL for GSDMB (eQTL effect size [β] 1·35 [95% CI 1·25-1·46], p<0·0001), and to a lesser extent showed an eQTL effect for post-GPI attachment to proteins phospholipase 3 (β 1·15 [1·08-1·22], p<0·0001). No SNPs were eQTLs for ORMDL3. By contrast, in PBMCs, the five core SNPs were associated only with expression of GSDMB and ORMDL3. Genotype at rs12936231 (in zona pellucida binding protein 2) showed the strongest associations across both genes (for GSDMB, eQTLβ 1·24 [1·15-1·32], p<0·0001; and for ORMDL3 (β 1·19 [1·12-1·24], p<0·0001). The eQTL effects of rs2305480 on GSDMB expression were replicated in lower airway cells from African American adults (β 1·29 [1·15-1·44], p<0·0001).InterpretationOur study suggests that SNPs regulating GSDMB expression in airway epithelial cells have a major role in childhood-onset asthma, whereas SNPs regulating the expression levels of 17q12-21 genes in resting blood cells are not central to asthma risk. Our genetic and gene expression data in African Americans and European Americans indicated GSDMB to be the leading candidate gene at this important asthma locus.FundingNational Institutes of Health, Office of the Director

Expression quantitative trait locus fine mapping of the 17q12–21 asthma locus in African American children: a genetic association and gene expression study

Background: African ancestry is associated with a higher prevalence and greater severity of asthma than European ancestries, yet genetic studies of the most common locus associated with childhood-onset asthma, 17q12–21, in African Americans have been inconclusive. The aim of this study was to leverage both the phenotyping of the Children's Respiratory and Environmental Workgroup (CREW) birth cohort consortium, and the reduced linkage disequilibrium in African Americans, to fine map the 17q12–21 locus. Methods: We first did a genetic association study and meta-analysis using 17q12–21 tag single-nucleotide polymorphisms (SNPs) for childhood-onset asthma in 1613 European American and 870 African American children from the CREW consortium. Nine tag SNPs were selected based on linkage disequilibrium patterns at 17q12–21 and their association with asthma, considering the effect allele under an additive model (0, 1, or 2 effect alleles). Results were meta-analysed with publicly available summary data from the EVE consortium (on 4303 European American and 3034 African American individuals) for seven of the nine SNPs of interest. Subsequently, we tested for expression quantitative trait loci (eQTLs) among the SNPs associated with childhood-onset asthma and the expression of 17q12–21 genes in resting peripheral blood mononuclear cells (PBMCs) from 85 African American CREW children and in upper airway epithelial cells from 246 African American CREW children; and in lower airway epithelial cells from 44 European American and 72 African American adults from a case-control study of asthma genetic risk in Chicago (IL, USA). Findings: 17q12–21 SNPs were broadly associated with asthma in European Americans. Only two SNPs (rs2305480 in gasdermin-B [GSDMB] and rs8076131 in ORMDL sphingolipid biosynthesis regulator 3 [ORMDL3]) were associated with asthma in African Americans, at a Bonferroni-corrected threshold of p<0·0055 (for rs2305480_G, odds ratio [OR] 1·36 [95% CI 1·12–1·65], p=0·0014; and for rs8076131_A, OR 1·37 [1·13–1·67], p=0·0010). In upper airway epithelial cells from African American children, genotype at rs2305480 was the most significant eQTL for GSDMB (eQTL effect size [β] 1·35 [95% CI 1·25–1·46], p<0·0001), and to a lesser extent showed an eQTL effect for post-GPI attachment to proteins phospholipase 3 (β 1·15 [1·08–1·22], p<0·0001). No SNPs were eQTLs for ORMDL3. By contrast, in PBMCs, the five core SNPs were associated only with expression of GSDMB and ORMDL3. Genotype at rs12936231 (in zona pellucida binding protein 2) showed the strongest associations across both genes (for GSDMB, eQTLβ 1·24 [1·15–1·32], p<0·0001; and for ORMDL3 (β 1·19 [1·12–1·24], p<0·0001). The eQTL effects of rs2305480 on GSDMB expression were replicated in lower airway cells from African American adults (β 1·29 [1·15–1·44], p<0·0001). Interpretation: Our study suggests that SNPs regulating GSDMB expression in airway epithelial cells have a major role in childhood-onset asthma, whereas SNPs regulating the expression levels of 17q12–21 genes in resting blood cells are not central to asthma risk. Our genetic and gene expression data in African Americans and European Americans indicated GSDMB to be the leading candidate gene at this important asthma locus.6 month embargo; published: 01 May 2020This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]