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Item Determinants of Lung Function Across Childhood in the Severe Asthma Research Program (SARP) 3(Elsevier, 2023) Gaffin, Jonathan M.; Petty, Carter R.; Sorkness, Ronald L.; Denlinger, Loren C.; Phillips, Brenda R.; Ly, Ngoc P.; Gaston, Benjamin; Ross, Kristie; Fitzpatrick, Anne; Bacharier, Leonard B.; DeBoer, Mark D.; Teague, W. Gerald; Wenzel, Sally E.; Ramratnam, Sima; Israel, Elliot; Mauger, David T.; Phipatanakul, Wanda; National Heart, Lung and Blood Institute’s Severe Asthma Research Program-3 Investigators; Pediatrics, School of MedicineBackground: Children with asthma are at risk for low lung function extending into adulthood, but understanding of clinical predictors is incomplete. Objective: We sought to determine phenotypic factors associated with FEV1 throughout childhood in the Severe Asthma Research Program 3 pediatric cohort. Methods: Lung function was measured at baseline and annually. Multivariate linear mixed-effects models were constructed to assess the effect of baseline and time-varying predictors of prebronchodilator FEV1 at each assessment for up to 6 years. All models were adjusted for age, predicted FEV1 by Global Lung Function Initiative reference equations, race, sex, and height. Secondary outcomes included postbronchodilator FEV1 and prebronchodilator FEV1/forced vital capacity. Results: A total of 862 spirometry assessments were performed for 188 participants. Factors associated with FEV1 include baseline Feno (B, -49 mL/log2 PPB; 95% CI, -92 to -6), response to a characterizing dose of triamcinolone acetonide (B, -8.4 mL/1% change FEV1 posttriamcinolone; 95% CI, -12.3 to -4.5), and maximal bronchodilator reversibility (B, -27 mL/1% change postbronchodilator FEV1; 95% CI, -37 to -16). Annually assessed time-varying factors of age, obesity, and exacerbation frequency predicted FEV1 over time. Notably, there was a significant age and sex interaction. Among girls, there was no exacerbation effect. For boys, however, moderate (1-2) exacerbation frequency in the previous 12 months was associated with -20 mL (95% CI, -39 to -2) FEV1 at each successive year. High exacerbation frequency (≥3) 12 to 24 months before assessment was associated with -34 mL (95% CI, -61 to -7) FEV1 at each successive year. Conclusions: In children with severe and nonsevere asthma, several clinically relevant factors predict FEV1 over time. Boys with recurrent exacerbations are at high risk of lower FEV1 through childhood.Item Genetic analyses identify GSDMB associated with asthma severity, exacerbations, and antiviral pathways(Elsevier, 2020) Li, Xingnan; Christenson, Stephanie A.; Modena, Brian; Li, Huashi; Busse, William W.; Castro, Mario; Denlinger, Loren C.; Erzurum, Serpil C.; Fahy, John V.; Gaston, Benjamin; Hastie, Annette T.; Israel, Elliot; Jarjour, Nizar N.; Levy, Bruce D.; Moore, Wendy C.; Woodruff, Prescott G.; Kaminski, Naftali; Wenzel, Sally E.; Bleecker, Eugene R.; Meyers, Deborah A.; Pediatrics, School of MedicineBackground The Chr17q12-21.2 region is the strongest and most consistently associated region with asthma susceptibility. The functional genes or single nucleotide polymorphisms (SNPs) are not obvious due to linkage disequilibrium. Objectives We sought to comprehensively investigate whole-genome sequence and RNA sequence from human bronchial epithelial cells to dissect functional genes/SNPs for asthma severity in the Severe Asthma Research Program. Methods Expression quantitative trait loci analysis (n = 114), correlation analysis (n = 156) of gene expression and asthma phenotypes, and pathway analysis were performed in bronchial epithelial cells and replicated. Genetic association for asthma severity (426 severe vs 531 nonsevere asthma) and longitudinal asthma exacerbations (n = 273) was performed. Results Multiple SNPs in gasdermin B (GSDMB) associated with asthma severity (odds ratio, >1.25) and longitudinal asthma exacerbations (P < .05). Expression quantitative trait loci analyses identified multiple SNPs associated with expression levels of post-GPI attachment to proteins 3, GSDMB, or gasdermin A (3.1 × 10−9 < P < 1.8 × 10−4). Higher expression levels of GSDMB correlated with asthma and greater number of exacerbations (P < .05). Expression levels of GSDMB correlated with genes involved in IFN signaling, MHC class I antigen presentation, and immune system pathways (false-discovery rate–adjusted P < .05). rs1031458 and rs3902920 in GSDMB colocalized with IFN regulatory factor binding sites and associated with GSDMB expression, asthma severity, and asthma exacerbations (P < .05). Conclusions By using a unique set of gene expression data from lung cells obtained using bronchoscopy from comprehensively characterized subjects with asthma, we show that SNPs in GSDMB associated with asthma severity, exacerbations, and GSDMB expression levels. Furthermore, its expression levels correlated with asthma exacerbations and antiviral pathways. Thus, GSDMB is a functional gene for both asthma susceptibility and severity.Item Mitochondrial DNA Copy Number Variation in Asthma Risk, Severity, and Exacerbations(medRxiv, 2023-12-05) Xu, Weiling; Hong, Yun Soo; Hu, Bo; Comhair, Suzy A. A.; Janocha, Allison J.; Zein, Joe G.; Chen, Ruoying; Meyers, Deborah A.; Mauger, David T.; Ortega, Victor E.; Bleecker, Eugene R.; Castro, Mario; Denlinger, Loren C.; Fahy, John V.; Israel, Elliot; Levy, Bruce D.; Jarjour, Nizar N.; Moore, Wendy C.; Wenzel, Sally E.; Gaston, Benjamin; Liu, Chunyu; Arking, Dan E.; Erzurum, Serpil C.; National Heart, Lung, and Blood Institute (NHLBI) Severe Asthma Research Program (SARP) and TOPMed mtDNA Working Group in NHLBI Trans-Omics for Precision Medicine (TOPMed) Consortium; Pediatrics, School of MedicineRationale: Although airway oxidative stress and inflammation are central to asthma pathogenesis, there is limited knowledge of the relationship of asthma risk, severity, or exacerbations to mitochondrial dysfunction, which is pivotal to oxidant generation and inflammation. Objectives: We investigated whether mitochondrial DNA copy number (mtDNA-CN) as a measure of mitochondrial function is associated with asthma diagnosis, severity, oxidative stress, and exacerbations. Methods: We measured mtDNA-CN in blood in two cohorts. In the UK Biobank (UKB), we compared mtDNA-CN in mild and moderate-severe asthmatics to non-asthmatics. In the Severe Asthma Research Program (SARP), we evaluated mtDNA-CN in relation to asthma severity, biomarkers of oxidative stress and inflammation, and exacerbations. Measures and main results: In UK Biobank, asthmatics (n = 29,768) have lower mtDNA-CN compared to non-asthmatics (n = 239,158) (beta, -0.026 [95% CI, -0.038 to -0.014], P = 2.46×10-5). While lower mtDNA-CN is associated with asthma, mtDNA-CN did not differ by asthma severity in either UKB or SARP. Biomarkers of inflammation show that asthmatics have higher white blood cells (WBC), neutrophils, eosinophils, fraction exhaled nitric oxide (FENO), and lower superoxide dismutase (SOD) than non-asthmatics, confirming greater oxidative stress in asthma. In one year follow-up in SARP, higher mtDNA-CN is associated with reduced risk of three or more exacerbations in the subsequent year (OR 0.352 [95% CI, 0.164 to 0.753], P = 0.007). Conclusions: Asthma is characterized by mitochondrial dysfunction. Higher mtDNA-CN identifies an exacerbation-resistant asthma phenotype, suggesting mitochondrial function is important in exacerbation risk.Item PrecISE: Precision Medicine in Severe Asthma: An adaptive platform trial with biomarker ascertainment(Elsevier, 2021) Israel, Elliot; Denlinger, Loren C.; Bacharier, Leonard B.; LaVange, Lisa M.; Moore, Wendy C.; Peters, Michael C.; Georas, Steve N.; Wright, Rosalind J.; Mauger, David T.; Noel, Patricia; Akuthota, Praveen; Bach, Julia; Bleecker, Eugene R.; Cardet, Juan Carlos; Carr, Tara F.; Castro, Mario; Cinelli, Angeles; Comhair, Suzy A.A.; Covar, Ronina A.; Alexander, Laura Crotty; DiMango, Emily A.; Erzurum, Serpil C.; Fahy, John V.; Fajt, Merritt L.; Gaston, Benjamin M.; Hoffman, Eric A.; Holguin, Fernando; Jackson, Daniel J.; Jain, Sonia; Jarjour, Nizar N.; Ji, Yuan; Kenyon, Nicholas J.; Kosorok, Michael R.; Kraft, Monica; Krishnan, Jerry A.; Kumar, Rajesh; Liu, Andrew H.; Liu, Mark C.; Ly, Ngoc P.; Marquis, M. Alison; Martinez, Fernando D.; Moy, James N.; O’Neal, Wanda K.; Ortega, Victor E.; Peden, David B.; Phipatanakul, Wanda; Ross, Kristie; Smith, Lewis J.; Szefler, Stanley J.; Teague, W. Gerald; Tulchinsky, Abigail F.; Vijayanand, Pandurangan; Wechsler, Michael E.; Wenzel, Sally E.; White, Steven R.; Zeki, Amir A.; Ivanova, Anastasia; Pediatrics, School of MedicineSevere asthma accounts for almost half the cost associated with asthma. Severe asthma is driven by heterogeneous molecular mechanisms. Conventional clinical trial design often lacks the power and efficiency to target subgroups with specific pathobiological mechanisms. Furthermore, the validation and approval of new asthma therapies is a lengthy process. A large proportion of that time is taken by clinical trials to validate asthma interventions. The National Institutes of Health Precision Medicine in Severe and/or Exacerbation Prone Asthma (PrecISE) program was established with the goal of designing and executing a trial that uses adaptive design techniques to rapidly evaluate novel interventions in biomarker-defined subgroups of severe asthma, while seeking to refine these biomarker subgroups, and to identify early markers of response to therapy. The novel trial design is an adaptive platform trial conducted under a single master protocol that incorporates precision medicine components. Furthermore, it includes innovative applications of futility analysis, cross-over design with use of shared placebo groups, and early futility analysis to permit more rapid identification of effective interventions. The development and rationale behind the study design are described. The interventions chosen for the initial investigation and the criteria used to identify these interventions are enumerated. The biomarker-based adaptive design and analytic scheme are detailed as well as special considerations involved in the final trial design.Item The Precision Interventions for Severe and/or Exacerbation-Prone (PrecISE) Asthma Network: an overview of Network organization, procedures and interventions(Elsevier, 2022-02) Georas, Steve N.; Wright, Rosalind J.; Ivanova, Anastasia; Israel, Elliot; LaVange, Lisa M.; Akuthota, Praveen; Carr, Tara F.; Denlinger, Loren C.; Fajt, Merritt L.; Kumar, Rajesh; O’Neal, Wanda K.; Phipatanakul, Wanda; Szefler, Stanley J.; Aronica, Mark A.; Bacharier, Leonard B.; Burbank, Allison J.; Castro, Mario; Alexander, Laura Crotty; Bamdad, Julie; Cardet, Juan Carlos; Comhair, Suzy A. A.; Covar, Ronina A.; DiMango, Emily A.; Erwin, Kim; Erzurum, Serpil C.; Fahy, John V.; Gaffin, Jonathan M.; Gaston, Benjamin; Gerald, Lynn B.; Hoffman, Eric A.; Holguin, Fernando; Jackson, Daniel J.; James, John; Jarjour, Nizar N.; Kenyon, Nicholas J.; Khatri, Sumita; Kirwan, John P.; Kraft, Monica; Krishnan, Jerry A.; Liu, Andrew H.; Liu, Mark C.; Marquis, M. Alison; Martinez, Fernando; Mey, Jacob; Moore, Wendy C.; Moy, James N.; Ortega, Victor E.; Peden, David B.; Pennington, Emily; Peters, Michael C.; Ross, Kristie; Sanchez, Maria; Smith, Lewis J.; Sorkness, Ronald L.; Wechsler, Michael E.; Wenzel, Sally E.; White, Steven R.; Zein, Joe; Zeki, Amir A.; Noel, Patricia; Pediatrics, School of MedicineAsthma is a heterogeneous disease, with multiple underlying inflammatory pathways and structural airway abnormalities that impact disease persistence and severity. Recent progress has been made in developing targeted asthma therapeutics, especially for subjects with eosinophilic asthma. However, there is an unmet need for new approaches to treat patients with severe and exacerbation prone asthma, who contribute disproportionately to disease burden. Extensive deep phenotyping has revealed the heterogeneous nature of severe asthma and identified distinct disease subtypes. A current challenge in the field is to translate new and emerging knowledge about different pathobiologic mechanisms in asthma into patient-specific therapies, with the ultimate goal of modifying the natural history of disease. Here we describe the Precision Interventions for Severe and/or Exacerbation Prone Asthma (PrecISE) Network, a groundbreaking collaborative effort of asthma researchers and biostatisticians from around the U.S. The PrecISE Network was designed to conduct phase II/proof of concept clinical trials of precision interventions in the severe asthma population, and is supported by the National Heart Lung and Blood Institute of the National Institutes of Health. Using an innovative adaptive platform trial design, the Network will evaluate up to six interventions simultaneously in biomarker-defined subgroups of subjects. We review the development and organizational structure of the Network, and choice of interventions being studied. We hope that the PrecISE Network will enhance our understanding of asthma subtypes and accelerate the development of therapeutics for of severe asthma.Item Responsiveness to Parenteral Corticosteroids and Lung Function Trajectory in Adults with Moderate-to-Severe Asthma(American Thoracic Society, 2021) Denlinger, Loren C.; Phillips, Brenda R.; Sorkness, Ronald L.; Bleecker, Eugene R.; Castro, Mario; DeBoer, Mark D.; Fitzpatrick, Anne M.; Hastie, Annette T.; Gaffin, Jonathan M.; Moore, Wendy C.; Peters, Michael C.; Peters, Stephen P.; Phipatanakul, Wanda; Cardet, Juan Carlos; Erzurum, Serpil C.; Fahy, John V.; Fajt, Merritt L.; Gaston, Benjamin; Levy, Bruce D.; Meyers, Deborah A.; Ross, Kristie; Teague, W. Gerald; Wenzel, Sally E.; Woodruff, Prescott G.; Zein, Joe; Jarjour, Nizar N.; Mauger, David T.; Israel, Elliot; Pediatrics, School of MedicineRationale: It is unclear why select patients with moderate-to-severe asthma continue to lose lung function despite therapy. We hypothesized that participants with the smallest responses to parenteral corticosteroids have the greatest risk of undergoing a severe decline in lung function. Objectives: To evaluate corticosteroid-response phenotypes as longitudinal predictors of lung decline. Methods: Adults within the NHLBI SARP III (Severe Asthma Research Program III) who had undergone a course of intramuscular triamcinolone at baseline and at ≥2 annual follow-up visits were evaluated. Longitudinal slopes were calculated for each participant’s post-bronchodilator FEV1% predicted. Categories of participant FEV1 slope were defined: severe decline, >2% loss/yr; mild decline, >0.5–2.0% loss/yr; no change, 0.5% loss/yr to <1% gain/yr; and improvement, ≥1% gain/yr. Regression models were used to develop predictors of severe decline. Measurements and Main Results: Of 396 participants, 78 had severe decline, 91 had mild decline, 114 had no change, and 113 showed improvement. The triamcinolone-induced difference in the post-bronchodilator FEV1% predicted (derived by baseline subtraction) was related to the 4-year change in lung function or slope category in univariable models (P < 0.001). For each 5% decrement in the triamcinolone-induced difference the FEV1% predicted, there was a 50% increase in the odds of being in the severe decline group (odds ratio, 1.5; 95% confidence interval, 1.3–1.8), when adjusted for baseline FEV1, exacerbation history, blood eosinophils and body mass index. Conclusions: Failure to improve the post-bronchodilator FEV1 after a challenge with parenteral corticosteroids is an evoked biomarker for patients at risk for a severe decline in lung function.Item Urinary total conjugated 3-bromotyrosine, asthma severity, and exacerbation risk(American Physiological Society, 2022) Wang, Zeneng; Xu, Weiling; Comhair, Suzy A. A.; Fu, Xiaoming; Shao, Zhili; Bearden, Rebecca; Zein, Joe G.; Bleecker, Eugene R.; Castro, Mario; Denlinger, Loren C.; Fahy, John V.; Israel, Elliot; Levy, Bruce D.; Jarjour, Nizar N.; Moore, Wendy C.; Wenzel, Sally E.; Mauger, David T.; Gaston, Benjamin; Hazen, Stanley L.; Erzurum, Serpil C.; Pediatrics, School of MedicineAsthma is an inflammatory disease of the airways characterized by eosinophil recruitment, eosinophil peroxidase release, and protein oxidation through bromination, which following tissue remodeling results in excretion of 3-bromotyrosine. Predicting exacerbations and reducing their frequency is critical for the treatment of severe asthma. In this study, we aimed to investigate whether urinary total conjugated bromotyrosine can discriminate asthma severity and predict asthma exacerbations. We collected urine from participants with severe (n = 253) and nonsevere (n = 178) asthma, and the number of adjudicated exacerbations in 1-yr longitudinal follow-up was determined among subjects enrolled in the Severe Asthma Research Program, a large-scale National Institutes of Health (NIH)-funded consortium. Urine glucuronidated bromotyrosine and total conjugated forms were quantified by hydrolysis with either glucuronidase or methanesulfonic acid, respectively, followed by liquid chromatography-tandem mass spectrometry analyses of free 3-bromotyrosine. Blood and sputum eosinophils were also counted. The majority of 3-bromotyrosine in urine was found to exist in conjugated forms, with glucuronidated bromotyrosine representing approximately a third, and free bromotyrosine less than 1% of total conjugated bromotyrosine. Total conjugated bromotyrosine was poorly correlated with blood (r2 = 0.038) or sputum eosinophils (r2 = 0.0069). Compared with participants with nonsevere asthma, participants with severe asthma had significantly higher urinary total conjugated bromotyrosine levels. Urinary total conjugated bromotyrosine was independently associated with asthma severity, correlated with the number of asthma exacerbations, and served as a predictor of asthma exacerbation risk over 1-yr of follow-up.Item Urinary total conjugated 3-bromotyrosine, asthma severity, and exacerbation risk(American Physiological Society, 2022-11) Wang, Zeneng; Xu, Weiling; Comhair, Suzy A. A.; Fu, Xiaoming; Shao, Zhili; Bearden, Rebecca; Zein, Joe G.; Bleecker, Eugene R.; Castro, Mario; Denlinger, Loren C.; Fahy, John V.; Israel, Elliot; Levy, Bruce D.; Jarjour, Nizar N.; Moore, Wendy C.; Wenzel, Sally E.; Mauger, David T.; Gaston, Benjamin; Hazen, Stanley L.; Erzurum, Serpil C.; Pediatrics, School of MedicineAsthma is an inflammatory disease of the airways characterized by eosinophil recruitment, eosinophil peroxidase release, and protein oxidation through bromination, which following tissue remodeling results in excretion of 3-bromotyrosine. Predicting exacerbations and reducing their frequency is critical for the treatment of severe asthma. In this study, we aimed to investigate whether urinary total conjugated bromotyrosine can discriminate asthma severity and predict asthma exacerbations. We collected urine from participants with severe (n = 253) and nonsevere (n = 178) asthma, and the number of adjudicated exacerbations in 1-yr longitudinal follow-up was determined among subjects enrolled in the Severe Asthma Research Program, a large-scale National Institutes of Health (NIH)-funded consortium. Urine glucuronidated bromotyrosine and total conjugated forms were quantified by hydrolysis with either glucuronidase or methanesulfonic acid, respectively, followed by liquid chromatography-tandem mass spectrometry analyses of free 3-bromotyrosine. Blood and sputum eosinophils were also counted. The majority of 3-bromotyrosine in urine was found to exist in conjugated forms, with glucuronidated bromotyrosine representing approximately a third, and free bromotyrosine less than 1% of total conjugated bromotyrosine. Total conjugated bromotyrosine was poorly correlated with blood (r2 = 0.038) or sputum eosinophils (r2 = 0.0069). Compared with participants with nonsevere asthma, participants with severe asthma had significantly higher urinary total conjugated bromotyrosine levels. Urinary total conjugated bromotyrosine was independently associated with asthma severity, correlated with the number of asthma exacerbations, and served as a predictor of asthma exacerbation risk over 1-yr of follow-up.