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Background Clustering key clinical characteristics of participants in the Severe Asthma Research Program (SARP), a large, multicenter prospective observational study of patients with asthma and healthy controls, has led to the identification of novel asthma phenotypes. Purpose To determine whether quantitative CT (qCT) could help distinguish between clinical asthma phenotypes. Materials and Methods A retrospective cross-sectional analysis was conducted with the use of qCT images (maximal bronchodilation at total lung capacity [TLC], or inspiration, and functional residual capacity [FRC], or expiration) from the cluster phenotypes of SARP participants (cluster 1: minimal disease; cluster 2: mild, reversible; cluster 3: obese asthma; cluster 4: severe, reversible; cluster 5: severe, irreversible) enrolled between September 2001 and December 2015. Airway morphometry was performed along standard paths (RB1, RB4, RB10, LB1, and LB10). Corresponding voxels from TLC and FRC images were mapped with use of deformable image registration to characterize disease probability maps (DPMs) of functional small airway disease (fSAD), voxel-level volume changes (Jacobian), and isotropy (anisotropic deformation index [ADI]). The association between cluster assignment and qCT measures was evaluated using linear mixed models. Results A total of 455 participants were evaluated with cluster assignments and CT (mean age ± SD, 42.1 years ± 14.7; 270 women). Airway morphometry had limited ability to help discern between clusters. DPM fSAD was highest in cluster 5 (cluster 1 in SARP III: 19.0% ± 20.6; cluster 2: 18.9% ± 13.3; cluster 3: 24.9% ± 13.1; cluster 4: 24.1% ± 8.4; cluster 5: 38.8% ± 14.4

The mechanisms by which environmental exposures contribute to the pathogenesis of lung fibrosis are unclear. Here, we demonstrate an increase in cadmium (Cd) and carbon black (CB), common components of cigarette smoke (CS) and environmental particulate matter (PM), in lung tissue from subjects with idiopathic pulmonary fibrosis (IPF). Cd concentrations were directly proportional to citrullinated vimentin (Cit-Vim) amounts in lung tissue of subjects with IPF. Cit-Vim amounts were higher in subjects with IPF, especially smokers, which correlated with lung function and were associated with disease manifestations. Cd/CB induced the secretion of Cit-Vim in an Akt1- and peptidylarginine deiminase 2 (PAD2)–dependent manner. Cit-Vim mediated fibroblast invasion in a 3D ex vivo model of human pulmospheres that resulted in higher expression of CD26, collagen, and α-SMA. Cit-Vim activated NF-κB in a TLR4-dependent fashion and induced the production of active TGF-β1, CTGF, and IL-8 along with higher surface expression of TLR4 in lung fibroblasts. To corroborate ex vivo findings, mice treated with Cit-Vim, but not Vim, independently developed a similar pattern of fibrotic tissue remodeling, which was TLR4 dependent. Moreover, wild-type mice, but not PAD2(−/−) and TLR4 mutant (MUT) mice, exposed to Cd/CB generated high amounts of Cit-Vim, in both plasma and bronchoalveolar lavage fluid, and developed lung fibrosis in a stereotypic manner. Together, these studies support a role for Cit-Vim as a damage-associated molecular pattern molecule (DAMP) that is generated by lung macrophages in response to environmental Cd/CB exposure. Furthermore, PAD2 might represent a promising target to attenuate Cd/CB-induced fibrosis.

Background: Five clinical clusters (early-onset increasing severity clusters 1, 2, and 4, late-onset severe cluster 3, and late-onset severe obstructed cluster 5) have been identified in the SARP cross-sectional cohort (n=726; Moore 2010). This approach demonstrated asthma heterogeneity and showed differential responses to biologic therapy (Bleecker 2019 ERS). Objective: Investigate longitudinal phenotypes of clinical clusters in the SARP longitudinal cohort. Methods: Subjects in longitudinal cohort (n=594) with 3-year (n=461) and 5-year (n=272) were assigned to clinical clusters using an 11-variable discriminant function. Phenotypes were compared using Kruskal-Wallis test. Results: Baseline clinical characteristics of five clusters in the longitudinal cohort were similar to the cross-sectional cohort. From baseline to Year 5, 2/3 of subjects remained in the same cluster and 1/6 each changed to more severe or milder clusters. Cluster 5 had consistently higher numbers of asthma exacerbations than clusters 1-4. Responses to a corticosteroid evoked phenotype (before and after 40 mg intramuscular triamcinolone): severe asthma clusters 3-5 had greater % increase in FEV1 than non-severe clusters (p Conclusions: SARP clinical clusters are reproducible in the longitudinal cohort. Severe clusters have better responses to corticosteroid. Cluster 5 has consistently greater asthma exacerbations over time. Longitudinal changes in FEV1 primarily determine cluster progression.

The zeolitic imidazolate framework (ZIF)-8/water-glycol slurry shows great potential in separating low carbon hydrocarbons. In the present study, the physical properties of the ZIF-8/water-glycol slurry were determined, and the hydrophobicity and glycophilicity of the ZIF-8 material were demonstrated by measuring the contact angle between liquid droplets with a ZIF-8 material, for the first time. It was observed that the increase in pressure could weaken the hydrophobicity of ZIF-8. In addition, the sorption kinetics of CH4 and C2H4 in the slurry were investigated. It was noted that the relatively high temperature and pressure could increase the dissolution rates of CH4 and C2H4 in the slurry. A kinetic model for describing the dissolution of CH4 and C2H4 in the slurry was proposed, wherein the diffusion of gas molecules in the glycol membrane around ZIF-8 particles and those in the inner pores of ZIF-8 were concurrently considered for the first time. The simulation results correlated with the experimental data. Finally, multistage simulation separation experiments for CH4/C2H4 gas mixtures using the slurry were performed. It was observed that after a four-stage simulation separation operation, the concentration of C2H4 decreased from 49.72 mol% in the feed gas to 4.68 mol%. The experimental and modeling results will be helpful for the practical separation application of the ZIF-8 slurry system.

Background: Severe asthma is heterogeneous, with different phenotypes and endotypes. Aims and Objectives: We identified subsets of benralizumab-treated patients (pts) with severe asthma by assignment to Severe Asthma Research Program (SARP) clinical clusters. Methods: Pts (N=2,281) from SIROCCO (Lancet 2016:2115; n=1,082) and CALIMA (Lancet 2016:2128; n=1,199) were assigned to clusters via a discriminant function based on 11 predictors. Drug responses were compared with the Kruskal-Wallis test (nominal p-values). Results: Pts met criteria for 4 of 5 SARP clusters. Cluster 2 pts (n=393) were 81% atopic with early onset moderate asthma (mean age 15 yrs). Cluster 4 pts (n=386) were 82% atopic with early onset severe asthma (mean age 11 yrs). Cluster 3 pts (n=641) were 50% atopic with late-onset severe asthma (mean age 47 yrs). Cluster 5 pts (n=861) were 55% atopic with late-onset asthma (mean age 33 yrs) and persistent airflow obstruction. All clusters had annual exacerbation rate reductions for combined benralizumab arms vs. placebo, which were greater in late-onset asthma clusters (Cluster 3, −48%; 5, −50%; p Conclusions: Benralizumab improved lung function and reduced exacerbations in all clusters, with greater effects in late-onset asthma Clusters 3 and 5 vs. early onset Clusters 2 and 4. This supports the importance of understanding asthma heterogeneity and responsiveness to targeted therapies.

Combination of IL-6 (non-Type 2 asthma) and FeNO or blood eosinophil count (Type 2 asthma) identified asthma endotypes related to asthma severity, exacerbations, and responsiveness to corticosteroids and potential for response to anti-Type 2 and anti-IL-6 treatment.

Background: CC16 is a protein produced by bronchial epithelial cells (BEC) that participates in host defense. Objectives: Our purpose is to investigate CC16 as a biomarker for COPD using systems biology in the SPIROMICS cohort. Methods: Genome-wide pQTL analyses of CC16 serum protein levels were performed in non-Hispanic Whites (n=1,874) and African Americans (n=403). Spearman correlation analyses between CC16 mRNA levels and other protein-coding genes (n=14,746) were performed using RNAseq data from BEC (n=131). Association analyses between CC16 SNPs/mRNA/protein and COPD-related phenotypes were performed using a generalized linear model. Results: The A allele of rs3741240 was associated with lower CC16 protein levels in non-Hispanic Whites (p=9x10-6) and African Americans (p=0.04). CC16 mRNA levels were positively correlated with CC16 protein levels (p=0.02). CC16 mRNA levels were positively correlated with MUC5B, IL12A, C3, TLR5, IL6, DPP4, and SFTPD, and negatively correlated with MUC5AC, IL18R1, and TLR6 at genome-wide significant level (p 1 vs. 0, OR=0.8, p=0.02). Conclusions: rs3741240 is a pQTL SNP for CC16 protein levels. CC16 mRNA levels are positively correlated with inflammation genes and negatively correlated with atopic genes. These findings are consistent with eQTL and co-expression analyses from SARP asthma cohort (n=107) (Li, 2018, ATS abstract). CC16 protein levels were associated with reduced future COPD exacerbations and will be further investigated longitudinally in SPIROMICS.

Background Genome-wide association studies (GWASs) have identified various genes associated with asthma, yet, causal genes or single nucleotide polymorphisms (SNPs) remain elusive. We sought to dissect functional genes/SNPs for asthma by combining expression quantitative trait loci (eQTLs) and GWASs. Methods Cis-eQTL analyses of 34 asthma genes were performed in cells from human bronchial epithelial biopsy (BEC, n = 107) and from bronchial alveolar lavage (BAL, n = 94). Results For TSLP-WDR36 region, rs3806932 (G allele protective against eosinophilic esophagitis) and rs2416257 (A allele associated with lower eosinophil counts and protective against asthma) were correlated with decreased expression of TSLP in BAL (P = 7.9 × 10−11 and 5.4 × 10−4, respectively) and BEC, but not WDR36. Surprisingly, rs1837253 (consistently associated with asthma) showed no correlation with TSLP expression levels. For ORMDL3-GSDMB region, rs8067378 (G allele protective against asthma) was correlated with decreased expression of GSDMB in BEC and BAL (P = 1.3 × 10−4 and 0.04) but not ORMDL3. rs992969 in the promoter region of IL33 (A allele associated with higher eosinophil counts and risk for asthma) was correlated with increased expression of IL33 in BEC (P = 1.3 × 10−6) but not in BAL. Conclusions Our study illustrates cell-type-specific regulation of the expression of asthma-related genes documenting SNPs in TSLP, GSDMB, IL33, HLA-DQB1, C11orf30, DEXI, CDHR3, and ZBTB10 affect asthma risk through cis-regulation of its gene expression. Whenever possible, disease-relevant tissues should be used for transcription analysis. SNPs in TSLP may affect asthma risk through up-regulating TSLP mRNA expression or protein secretion. Further functional studies are warranted.

Idiopathic pulmonary fibrosis (IPF) is a fatal progressive fibrotic lung disease characterized by the presence of invasive myofibroblasts in the lung. Currently, there are only two FDA-approved drugs (pirfenidone and nintedanib) for the treatment of IPF. There are no defined criteria to guide specific drug therapy. New methodologies are needed not only to predict personalized drug therapy, but also to screen novel molecules that are on the horizon for treatment of IPF. We have developed a model system that exploits the invasive phenotype of IPF lung tissue. This ex vivo 3D model uses lung tissue from patients to develop pulmospheres. Pulmospheres are 3D spheroids composed of cells derived exclusively from primary lung biopsies and inclusive of lung cell types reflective of those in situ, in the patient. We tested the pulmospheres of 20 subjects with IPF and 9 control subjects to evaluate the responsiveness of individual patients to antifibrotic drugs. Clinical parameters and outcomes were also followed in the same patients. Our results suggest that pulmospheres simulate the microenvironment in the lung and serve as a personalized and predictive model for assessing responsiveness to antifibrotic drugs in patients with IPF.

Autoimmunity has been implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF); however, the repertoire of autoantigens involved in this disease and the clinical relevance of these autoimmune responses are still being explored. Our initial discovery assays demonstrated that circulating and intrapulmonary vimentin levels are increased in IPF patients. Subsequent studies showed native vimentin induced HLA-DR–dependent in vitro proliferation of CD4 T cells from IPF patients and enhanced the production of IL-4, IL-17, and TGF-β1 by these lymphocytes in contrast to normal control specimens. Vimentin supplementation of IPF PBMC cultures also resulted in HLA-DR–dependent production of IgG with anti-vimentin specificities. Circulating anti-vimentin IgG autoantibody levels were much greater in IPF subjects from the University of Alabama at Birmingham (n = 102) and the University of Pittsburgh (U. Pitt., n = 70) than in normal controls. Anti-vimentin autoantibody levels in IPF patients were HLA biased and inversely correlated with physiological measurements of lung function (i.e., forced expiratory volumes and diffusing capacities). Despite considerable intergroup differences in transplant-free survival between these two independent IPF cohorts, serious adverse outcomes were most frequent among the patients within each population that had the highest anti-vimentin autoantibody levels (University of Alabama at Birmingham: hazard ratio 2.5, 95% confidence interval 1.2–5.3, p = 0.012; University of Pittsburgh: hazard ratio 2.7, 95% confidence interval 1.3–5.5, p = 0.006). These data show that anti-vimentin autoreactivity is prevalent in IPF patients and is strongly associated with disease manifestations. These findings have implications with regard to the pathogenesis of this enigmatic disease and raise the possibility that therapies specifically directed at these autoimmune processes could have therapeutic efficacy.

Background: Smokers has been clustered into COPD and non-COPD clusters (Li, ATS 2016). Smokers with preserved lung function may have COPD symptoms, exacerbations, and usage of respiratory medicine (Woodruff, NEJM 2016, 374:1811-21). Objectives: We aim to compare clinical characteristics of four clusters mainly composed of smokers with preserved lung function. Methods: Clinical characteristics were compared using the Kruskal-Wallis test and chi-square test. Results: C1 consists of resistant smokers with normal lung function, early emphysema, lower HCU and inhaled steroid (ICS) use, and lower symptom scores. C2 consists of heavy smokers with normal lung function, early emphysema, higher HCU and ICS use, and higher blood neutrophils. C3 has normal lung function, no emphysema, and lower HCU and ICS use. C4 has lower lung function, no emphysema, higher HCU and ICS use, higher “label” of asthma, higher inflammation, and higher symptom scores. Conclusions: Four distinct endophenotypic clusters mainly composed of smokers with preserved lung function have been identified. This study supports heterogeneity of smokers and indicates the distinction between smokers with preserved lung function and COPD is not as simple as measuring spirometry alone .

Background: The SARP1/2 cluster analysis identified 5 clinical asthma phenotypes that reflect inflammatory mechanisms: a spectrum of early onset allergic asthma (Clusters 1,2,4), late onset severe asthma (Cluster 3) and severe asthma with COPD characteristics (Cluster 5). Aims: Evaluate reproducibility and stability of SARP1/2 clinical cluster phenotypes in SARP3, a 3-year longitudinal cohort enriched for severe asthma. Methods: SARP3 subjects > 12 years old (n= 594) were assigned to SARP1/2 clusters using 11 variables and compared to the SARP1/2 cohort (n=1176). Subjects in both SARP1/2 and SARP3 (n=68) were assigned to clusters twice using unique SARP1/2 and 3 data. Results: The SARP3 cohort is skewed toward severe asthma clusters 3(16%), 4(15%) and 5(19%). SARP3 subjects are older with longer disease duration (p Conclusions: All five SARP1/2 clinical cluster phenotypes are reproducible in SARP3 with a shift toward more severe clusters (3,4,5). In a subset of SARP subjects with longitudinal data there was heterogeneity in the progression of disease severity that was associated with changes in baseline lung function. These results suggest that a clinical approach guided by monitoring of lung function could identify patients at risk for disease progression.

Objective: Genome-wide association studies (GWASs) have identified genes associated with asthma, however expression of these genes in asthma-relevant tissues has not been studied. This study tested expression and correlation between GWAS-identified asthma genes and asthma or asthma severity. Methods: Correlation analyses of expression levels of GWAS-identified asthma genes and asthma-related biomarkers were performed in cells from human bronchial epithelial biopsy (BEC, n = 107) and bronchial alveolar lavage (BAL, n = 94). Results: Expression levels of asthma genes between BEC and BAL and with asthma or asthma severity were weakly correlated. The expression levels of IL18R1 were consistently higher in asthma than controls or in severe asthma than mild/moderate asthma in BEC and BAL (p < 0.05). In RAD50-IL13 region, the expression levels of RAD50, not IL4, IL5, or IL13, were positively correlated between BEC and BAL (ρ = 0.53, P = 4.5 × 10−6). The expression levels of IL13 were positively correlated with IL5 in BEC (ρ = 0.35, P = 1.9 × 10−4) and IL4 in BAL (ρ = 0.42, P = 2.5 × 10−5), respectively. rs3798134 in RAD50, a GWAS-identified SNP, was correlated with IL13 expression and the expression levels of IL13 were correlated with asthma (P = 0.03). rs17772583 in RAD50 was significantly correlated with RAD50 expression in BAL and BEC (P = 7.4 × 10−7 and 0.04) but was not associated with asthma. Conclusions: This is the first report studying the expression of GWAS-identified asthma genes in BEC and BAL. IL13, rather than RAD50, IL4, or IL5, is more likely to be the asthma susceptibility gene. Our study illustrates tissue-specific expression of asthma-related genes. Therefore, whenever possible, disease-relevant tissues should be used for transcription analysis.

Retinal pigment epithelium-specific protein 65 kDa (RPE65) is a protein responsible for isomerization of all-trans-retinaldehyde to its photoactive 11-cis-retinaldehyde and is essential for the visual cycle. RPE65 mutations can cause severe, early onset retinal diseases such as Leber congenital amaurosis (LCA). A naturally occurring rodent model of LCA with a recessive nonsense Rpe65 mutation, the rd12 mouse, displays a profoundly diminished rod electroretinogram (ERG), an absence of 11-cis-retinaldehyde and rhodopsin, an overaccumulation of retinyl esters in retinal pigmented epithelial (RPE) cells, and photoreceptor degeneration. rd12 mice were injected subretinally at postnatal day 14 with rAAV5-CBA-hRPE65 vector. RPE65 expression was found over large areas of RPE soon after treatment. This led to improved rhodopsin levels with ERG signals restored to near normal. Retinyl ester levels were maintained at near normal, and fundus and retinal morphology remained normal. All parameters of restored retinal health remained stable for at least 7 months. The Morris water maze behavioral test was modified to test rod function under very dim light; rd12 mice treated in one eye performed similar to normally sighted C57BL/6J mice, while untreated rd12 mice performed very poorly, demonstrating that gene therapy can restore normal vision-dependent behavior in a congenitally blind animal.

The National Heart, Lung, and Blood Institute has sponsored several asthma clinical networks, but the Severe Asthma Research Program (SARP) is unique, because it is not a clinical trials network, and it includes both adults and children. Investigators in SARP have comprehensively characterized 1,644 patients with asthma over the past 10 years, including 583 individuals with severe asthma and 300 children below the age of 18 years. The diversity in clinical characteristics, physiologic measures, and biomarkers in a large number of subjects across the ages provides an ideal cohort in which to investigate asthma heterogeneity. Using both biased and unbiased approaches, multiple asthma phenotypes have been described in SARP. These phenotypic analyses have improved our understanding of heterogeneity in asthma, and may provide a starting point to transform clinical practice through the evidence-based classification of disease severity. Although these new phenotypes strive to make order out of a heterogeneous group of patients, they are limited by that heterogeneity. There may be large groups of patients, especially those with milder asthma, that can be grouped into a clinical phenotype to guide therapy, but there will always be patients on the “edge” of a phenotype who will not fit into these groupings. In the SARP cluster analysis, subjects on the “edge” of a phenotype frequently had lung function that was better or worse than other subjects in the same cluster, despite similar clinical characteristics. This suggests that different pathophysiologic mechanisms may be responsible for decrements in lung function in some subjects. This is extremely important for subjects with severe asthma who may be on the “edge” of two phenotypes that may be driven by different pathobiologic mechanisms that warrant different therapeutic approaches.

Background Clinical cluster analysis from the Severe Asthma Research Program (SARP) identified 5 asthma subphenotypes that represent the severity spectrum of early-onset allergic asthma, late-onset severe asthma, and severe asthma with chronic obstructive pulmonary disease characteristics. Analysis of induced sputum from a subset of SARP subjects showed 4 sputum inflammatory cellular patterns. Subjects with concurrent increases in eosinophil (≥2%) and neutrophil (≥40%) percentages had characteristics of very severe asthma. Objective To better understand interactions between inflammation and clinical subphenotypes, we integrated inflammatory cellular measures and clinical variables in a new cluster analysis. Methods Participants in SARP who underwent sputum induction at 3 clinical sites were included in this analysis (n = 423). Fifteen variables, including clinical characteristics and blood and sputum inflammatory cell assessments, were selected using factor analysis for unsupervised cluster analysis. Results Four phenotypic clusters were identified. Cluster A (n = 132) and B (n = 127) subjects had mild-to-moderate early-onset allergic asthma with paucigranulocytic or eosinophilic sputum inflammatory cell patterns. In contrast, these inflammatory patterns were present in only 7% of cluster C (n = 117) and D (n = 47) subjects who had moderate-to-severe asthma with frequent health care use despite treatment with high doses of inhaled or oral corticosteroids and, in cluster D, reduced lung function. The majority of these subjects (>83%) had sputum neutrophilia either alone or with concurrent sputum eosinophilia. Baseline lung function and sputum neutrophil percentages were the most important variables determining cluster assignment. Conclusion This multivariate approach identified 4 asthma subphenotypes representing the severity spectrum from mild-to-moderate allergic asthma with minimal or eosinophil-predominant sputum inflammation to moderate-to-severe asthma with neutrophil-predominant or mixed granulocytic inflammation.

Background The IL6R single nucleotide polymorphism (SNP) rs4129267 has recently been identified as an asthma susceptibility locus in subjects of European ancestry but has not been characterized with respect to asthma severity. The SNP rs4129267 is in linkage disequilibrium ( r 2 = 1) with the IL6R coding SNP rs2228145 (Asp 358 Ala). This IL6R coding change increases IL-6 receptor (IL-6R) shedding and promotes IL-6 transsignaling. Objectives We sought to evaluate the IL6R SNP rs2228145 with respect to asthma severity phenotypes. Methods The IL6R SNP rs2228145 was evaluated in subjects of European ancestry with asthma from the Severe Asthma Research Program (SARP). Lung function associations were replicated in the Collaborative Study on the Genetics of Asthma (CSGA) cohort. Serum soluble IL-6R levels were measured in subjects from SARP. Immunohistochemistry was used to qualitatively evaluate IL-6R protein expression in bronchoalveolar lavage cells and endobronchial biopsies. Results The minor C allele of IL6R SNP rs2228145 was associated with a lower percent predicted FEV 1 in the SARP cohort ( P = .005), the CSGA cohort ( P = .008), and in a combined cohort analysis ( P = .003). Additional associations with percent predicted forced vital capacity (FVC), FEV 1 /FVC ratio, and PC 20 were observed. The rs2228145 C allele (Ala 358 ) was more frequent in severe asthma phenotypic clusters. Elevated serum soluble IL-6R levels were associated with lower percent predicted FEV 1 ( P = .02) and lower percent predicted FVC ( P = .008) (n = 146). IL-6R protein expression was observed in bronchoalveolar lavage macrophages, airway epithelium, vascular endothelium, and airway smooth muscle. Conclusions The IL6R coding SNP rs2228145 (Asp 358 Ala) is a potential modifier of lung function in subjects with asthma and might identify subjects at risk for more severe asthma. IL-6 transsignaling might have a pathogenic role in the lung.

Two recent large meta-analyses of genome-wide association studies of lung function in general populations of European descent identified 11 candidate genes/regions. The importance of these genes in lung function in white and African American subjects with asthma is unknown.To determine whether genes that regulate lung function in general populations are associated with lung function abnormalities in subjects with asthma from different racial groups.Single nucleotide polymorphisms (SNPs) were tested in 5 asthma populations (N = 1441) for association with pulmonary function, and meta-analysis was performed across populations. The SNPs with the highest significance were then tested for association with bronchodilator reversibility and bronchial hyperresponsiveness to methacholine. A joint analysis of consistently replicated SNPs was performed to predict lung function in asthma.Hedgehog interacting protein (HHIP) on chromosome 4q31 was associated with lung function in all 5 populations (rs1512288: P(meta) = 9.62E-05 and 3.23E-05 for percent predicted FEV(1) [ppFEV(1)] and percent predicted forced vital capacity [ppFVC], respectively). The SNPs in HHIP were also associated with reversibility (P .05) but not bronchial hyperresponsiveness to methacholine. Because of differences in linkage disequilibrium in the African American subjects, the most relevant SNPs in HHIP were identified. A subset of normal lung function genes, including HHIP, family with sequence similarity 13, member A (FAM13A), and patched homolog 1 (PTCH1), together predict lung function abnormalities, a measure of severity in white and African American subjects with asthma.A subset of the genes, including HHIP, that regulate lung function in general populations are associated with abnormal lung function in asthma in non-Hispanic white and African American subjects.

The Severe Asthma Research Program cohort includes subjects with persistent asthma who have undergone detailed phenotypic characterization. Previous univariate methods compared features of mild, moderate, and severe asthma.To identify novel asthma phenotypes using an unsupervised hierarchical cluster analysis.Reduction of the initial 628 variables to 34 core variables was achieved by elimination of redundant data and transformation of categorical variables into ranked ordinal composite variables. Cluster analysis was performed on 726 subjects.Five groups were identified. Subjects in Cluster 1 (n = 110) have early onset atopic asthma with normal lung function treated with two or fewer controller medications (82%) and minimal health care utilization. Cluster 2 (n = 321) consists of subjects with early-onset atopic asthma and preserved lung function but increased medication requirements (29% on three or more medications) and health care utilization. Cluster 3 (n = 59) is a unique group of mostly older obese women with late-onset nonatopic asthma, moderate reductions in FEV(1), and frequent oral corticosteroid use to manage exacerbations. Subjects in Clusters 4 (n = 120) and 5 (n = 116) have severe airflow obstruction with bronchodilator responsiveness but differ in to their ability to attain normal lung function, age of asthma onset, atopic status, and use of oral corticosteroids.Five distinct clinical phenotypes of asthma have been identified using unsupervised hierarchical cluster analysis. All clusters contain subjects who meet the American Thoracic Society definition of severe asthma, which supports clinical heterogeneity in asthma and the need for new approaches for the classification of disease severity in asthma.

Because three-axle heavy-vehicle with front-wheel steering has big radius at low speed and bad stability at high speed, in order to improve heavy vehicle steering performance at different speed, the multi-axle dynamic steering technology is put forward. Selecting zero side-slip angle of mass center and proportional control strategy to control vehicle, Using MATLAB, the steering performance of the three-axle vehicle with different steering modes are simulated. The result shows that multi-axle dynamic steering can decrease the steering radius at low speed and improve vehicle stability at high speed.

Background Recent meta-analyses of genome-wide association studies in general populations of European descent have identified 28 loci for lung function. Objective We sought to identify novel lung function loci specifically for asthma and to confirm lung function loci identified in general populations. Methods Genome-wide association studies of lung function (percent predicted FEV 1 [ppFEV 1 ], percent predicted forced vital capacity, and FEV 1 /forced vital capacity ratio) were performed in 4 white populations of European descent (n = 1544), followed by meta-analyses. Results Seven of 28 previously identified lung function loci ( HHIP , FAM13A , THSD4 , GSTCD , NOTCH4-AGER , RARB , and ZNF323 ) identified in general populations were confirmed at single nucleotide polymorphism (SNP) levels ( P IL12A , IL12RB1 , STAT4 , and IRF2 ) associated with ppFEV 1 ( P −4 ) belong to the T H 1 or IL-12 cytokine family pathway. By using a linear additive model, these 4 T H 1 pathway SNPs cumulatively explained 2.9% to 7.8% of the variance in ppFEV 1 values in 4 populations ( P = 3 × 10 −11 ). Genetic scores of these 4 SNPs were associated with ppFEV 1 values ( P = 2 × 10 −7 ) and the American Thoracic Society severe asthma classification ( P = .005) in the Severe Asthma Research Program population. T H 2 pathway genes ( IL13 , TSLP , IL33 , and IL1RL1 ) conferring asthma susceptibility were not associated with lung function. Conclusion Genes involved in airway structure/remodeling are associated with lung function in both general populations and asthmatic subjects. T H 1 pathway genes involved in anti-virus/bacterial infection and inflammation modify lung function in asthmatic subjects. Genes associated with lung function that might affect asthma severity are distinct from those genes associated with asthma susceptibility.

Background Genome-wide association studies (GWASs) of asthma have consistently implicated the ORM1-like 3 and gasdermin B (ORMDL3-GSDMB) , IL33 , IL-1 receptor–like 1 and IL-18 receptor 1 (IL1RL1-IL18R1) , RAD50-IL13 , thymic stromal lymphopoietin and WD repeat domain 36 region (TSLP-WDR36) , and HLA-DR/DQ regions. Objective A GWAS of asthma was performed in a non-Hispanic white population. Methods A GWAS was performed in 813 Severe Asthma Research Program/Collaborative Studies on the Genetics of Asthma/Chicago Asthma Genetics Study cases and 1564 control subjects. The GWAS results were compared with those of the published GWASs of autoimmune diseases. Results Multiple single nucleotide polymorphisms in the TNFAIP3 interacting protein 1 (TNIP1) gene, which interacts with TNFAIP3 and inhibits the TNF-α–induced nuclear factor κB inflammation pathway, were associated with asthma: rs1422673 ( P = 3.44 × 10 −7 ) and rs10036748 ( P = 1.41 × 10 −6 , r 2 = 0.67). rs1422673 was also associated with asthma in the published GABRIEL ( P = .018) and EVE ( P = 1.31 × 10 −5 ) studies. The minor allele T of rs20541 in IL13 is the risk allele for asthma but the protective allele for psoriasis. The minor allele T of rs2395185 in HLA-DRA is the risk allele for asthma but the protective allele for ulcerative colitis. The minor allele A of rs2872507 in GSDMB is the protective allele for asthma but the risk allele for rheumatoid arthritis, Crohn disease, and ulcerative colitis. The T allele of rs10036748 in the TNIP1 gene is the minor protective allele for asthma but the minor or major risk allele for systemic lupus erythematosus and systemic sclerosis in non-Hispanic white or Chinese subjects, respectively. Conclusions Our study suggests that single nucleotide polymorphisms associated with both asthma and autoimmune diseases might have opposite effects on immunopathogenesis.

Xingnan Li, PhD, MS1, Elizabeth J. Ampleford, PhD1, Timothy D. Howard, PhD1, Wendy C. Moore, MD1, Huashi Li, MS1, William W. Busse, MD2, Mario Castro, MD3, Serpil C. Erzurum, MD4, Anne M. Fitzpatrick, PhD5, Benjamin Gaston, MD6, Elliot Israel, MD7, Nizar N. Jarjour, MD8, W. Gerald Teague, MD6, Sally E. Wenzel, MD9, Gregory A. Hawkins, PhD1, Eugene R. Bleecker, MD1, and Deborah A. Meyers, PhD1 1Center for Genomics and Personalized Medicine Research, Wake Forest University School of Medicine, Winston Salem, NC

Our previous studies demonstrated that exposure to hypoxia increases pulmonary artery pressure and plasma endothelin-1 (ET-1) levels and selectively enhances ET-1 gene expression in rat lung. The current study examined the effects of hypoxia (48 h, 10% O2, 1 atm) on ET-1 and endothelin A (ETA) and ETB receptor steady-state mRNA levels in lung, heart, pulmonary artery, thoracic aorta, superior vena cava, kidney, spleen, and liver of the rat. In lung, hypoxic exposure was associated with significant increases in ET-1 mRNA (4.1-fold), ET-1 peptide (1.5-fold) and ETA mRNA (2.3-fold) levels; ETB mRNA levels were unchanged. ET-1 mRNA was increased in response to hypoxia in pulmonary artery but not in aorta; both ETA and ETB receptor steady-state mRNA levels were increased in thoracic aorta, left atrium, and right ventricle, and tended to be increased in right atrium of hypoxia-exposed rats, compared with air controls. ETB but not ETA receptor steady-state mRNA levels were increased in pulmonary artery of hypoxia-exposed rats. No change in expression of either ET receptor steady-state mRNA levels was seen in organs perfused by the systemic vascular bed. In no case were ET receptor mRNA levels in hypoxic rats reduced below air control levels, despite elevations in local and/or circulating ET-1. These findings are consistent with a role for ET-1, acting through ETA receptors, in the pathogenesis of hypoxia-induced pulmonary hypertension.

Background Asthma in children is a heterogeneous disorder with many phenotypes. Although unsupervised cluster analysis is a useful tool for identifying phenotypes, it has not been applied to school-age children with persistent asthma across a wide range of severities. Objectives This study determined how children with severe asthma are distributed across a cluster analysis and how well these clusters conform to current definitions of asthma severity. Methods Cluster analysis was applied to 12 continuous and composite variables from 161 children at 5 centers enrolled in the Severe Asthma Research Program. Results Four clusters of asthma were identified. Children in cluster 1 (n = 48) had relatively normal lung function and less atopy. Children in cluster 2 (n = 52) had slightly lower lung function, more atopy, and increased symptoms and medication use. Cluster 3 (n = 32) had greater comorbidity, increased bronchial responsiveness, and lower lung function. Cluster 4 (n = 29) had the lowest lung function and the greatest symptoms and medication use. Predictors of cluster assignment were asthma duration, the number of asthma controller medications, and baseline lung function. Children with severe asthma were present in all clusters, and no cluster corresponded to definitions of asthma severity provided in asthma treatment guidelines. Conclusion Severe asthma in children is highly heterogeneous. Unique phenotypic clusters previously identified in adults can also be identified in children, but with important differences. Larger validation and longitudinal studies are needed to determine the baseline and predictive validity of these phenotypic clusters in the larger clinical setting.

Patients with severe asthma have increased granulocytes in their sputum compared with patients with mild to moderate asthma.We hypothesized that inflammatory granulocytes in sputum may identify specific asthma severity phenotypes and are associated with different patterns of inflammatory proteins in sputum supernatants.This hypothesis was tested in 242 patients with asthma enrolled in the Severe Asthma Research Program who provided sputum samples for cell count, differential cell determinations, cell lysates for Western blot, and supernatant analyses by inflammatory protein microarrays and ELISAs. ANOVA and multiple linear regression models tested mediator associations.Stratified by sputum granulocytes,2% oror = 2% eosinophils and40% oror = 40% neutrophils, subjects with both increased eosinophils and neutrophils had the lowest lung function and increased symptoms and health care use. Subjects with elevated eosinophils with or without increased neutrophils had significantly increased fraction exhaled nitric oxide (FeNO) and serum eosinophils and greater frequency of daily beta-agonist use. Microarray data stratified by granulocytes revealed 25 to 28 inflammatory proteins increased2-fold in sputa withor = 40% neutrophils. Microarray analyses stratified by severity of asthma identified 6 to 9 proteins increased2-fold in sputa in subjects with severe asthma compared with nonsevere asthma. ELISA data stratified by sputum granulocytes showed significant increases in brain-derived neurotrophic factor, IL-1beta, and macrophage inflammatory protein 3alpha/CCL20 for those withor = 40% neutrophils; these mediators demonstrated positive associations with neutrophil counts.Combined increased sputum eosinophils and neutrophils identified patients with asthma with the lowest lung function, worse asthma control, and increased symptoms and health care requirements. Inflammatory protein analyses of sputum supernatants found novel mediators increased in patients with asthma, predominantly associated with increased sputum neutrophils.