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Qian ET, Gatto CL, Amusina O, Dear ML, Hiser W, Buie R, Kripalani S, Harrell FE, Freundlich RE, Gao Y, Gong W, Hennessy C, Grooms J, Mattingly M, Bellam SK, Burke J, Zakaria A, Vasilevskis EE, Billings FT, Pulley JM, Bernard GR, Lindsell CJ, Rice TW. Assessment of Awake Prone Positioning in Hospitalized Adults With COVID-19: A Nonrandomized Controlled Trial. JAMA Intern Med 2022; 182:612-621. [PMID: 35435937 PMCID: PMC9016608 DOI: 10.1001/jamainternmed.2022.1070] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
IMPORTANCE Awake prone positioning may improve hypoxemia among patients with COVID-19, but whether it is associated with improved clinical outcomes remains unknown. OBJECTIVE To determine whether the recommendation of awake prone positioning is associated with improved outcomes among patients with COVID-19-related hypoxemia who have not received mechanical ventilation. DESIGN, SETTING, AND PARTICIPANTS This pragmatic nonrandomized controlled trial was conducted at 2 academic medical centers (Vanderbilt University Medical Center and NorthShore University HealthSystem) during the COVID-19 pandemic. A total of 501 adult patients with COVID-19-associated hypoxemia who had not received mechanical ventilation were enrolled from May 13 to December 11, 2020. INTERVENTIONS Patients were assigned 1:1 to receive either the practitioner-recommended awake prone positioning intervention (intervention group) or usual care (usual care group). MAIN OUTCOMES AND MEASURES Primary outcome analyses were performed using a bayesian proportional odds model with covariate adjustment for clinical severity ranking based on the World Health Organization ordinal outcome scale, which was modified to highlight the worst level of hypoxemia on study day 5. RESULTS A total of 501 patients (mean [SD] age, 61.0 [15.3] years; 284 [56.7%] were male; and most [417 (83.2%)] were self-reported non-Hispanic or non-Latinx) were included. Baseline severity was comparable between the intervention vs usual care groups, with 170 patients (65.9%) vs 162 patients (66.7%) receiving oxygen via standard low-flow nasal cannula, 71 patients (27.5%) vs 62 patients (25.5%) receiving oxygen via high-flow nasal cannula, and 16 patients (6.2%) vs 19 patients (7.8%) receiving noninvasive positive-pressure ventilation. Nursing observations estimated that patients in the intervention group spent a median of 4.2 hours (IQR, 1.8-6.7 hours) in the prone position per day compared with 0 hours (IQR, 0-0.7 hours) per day in the usual care group. On study day 5, the bayesian posterior probability of the intervention group having worse outcomes than the usual care group on the modified World Health Organization ordinal outcome scale was 0.998 (posterior median adjusted odds ratio [aOR], 1.63; 95% credibility interval [CrI], 1.16-2.31). However, on study days 14 and 28, the posterior probabilities of harm were 0.874 (aOR, 1.29; 95% CrI, 0.84-1.99) and 0.673 (aOR, 1.12; 95% CrI, 0.67-1.86), respectively. Exploratory outcomes (progression to mechanical ventilation, length of stay, and 28-day mortality) did not differ between groups. CONCLUSIONS AND RELEVANCE In this nonrandomized controlled trial, prone positioning offered no observed clinical benefit among patients with COVID-19-associated hypoxemia who had not received mechanical ventilation. Moreover, there was substantial evidence of worsened clinical outcomes at study day 5 among patients recommended to receive the awake prone positioning intervention, suggesting potential harm. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT04359797.
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Affiliation(s)
- Edward Tang Qian
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Cheryl L Gatto
- Vanderbilt Institute for Clinical and Translational Research, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Olga Amusina
- Critical Care Services, NorthShore University HealthSystem, Evanston, Illinois.,Department of Biobehavioral Nursing Science, University of Illinois, Chicago, College of Nursing, Chicago
| | - Mary Lynn Dear
- Vanderbilt Institute for Clinical and Translational Research, Vanderbilt University Medical Center, Nashville, Tennessee
| | - William Hiser
- Vanderbilt Institute for Clinical and Translational Research, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Reagan Buie
- Vanderbilt Institute for Clinical and Translational Research, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Sunil Kripalani
- Section of Hospital Medicine, Division of General Internal Medicine and Public Health, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Frank E Harrell
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Robert E Freundlich
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee.,Division of Anesthesiology Critical Care Medicine, Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Yue Gao
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Wu Gong
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Cassandra Hennessy
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Jillann Grooms
- School of Nursing and Health Sciences, North Park University, Chicago, Illinois
| | - Megan Mattingly
- Critical Care Services, NorthShore University HealthSystem, Evanston, Illinois
| | - Shashi K Bellam
- Division of Pulmonary and Critical Care, Department of Medicine, NorthShore University HealthSystem, Evanston, Illinois
| | - Jessica Burke
- Section of Hospital Medicine, Division of General Internal Medicine and Public Health, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Arwa Zakaria
- Section of Hospital Medicine, Division of General Internal Medicine and Public Health, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Eduard E Vasilevskis
- Section of Hospital Medicine, Division of General Internal Medicine and Public Health, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Frederic T Billings
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jill M Pulley
- Vanderbilt Institute for Clinical and Translational Research, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Gordon R Bernard
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Christopher J Lindsell
- Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Todd W Rice
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
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Biblowitz K, Lee C, Zhu D, Noth I, Vij R, Strek ME, Bellam SK, Adegunsoye A. Association of antinuclear antibody seropositivity with inhaled environmental exposures in patients with interstitial lung disease. ERJ Open Res 2021; 7:00254-2021. [PMID: 34761002 PMCID: PMC8573239 DOI: 10.1183/23120541.00254-2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 08/02/2021] [Indexed: 11/10/2022] Open
Abstract
Background Interstitial lung diseases (ILDs) are diffuse parenchymal lung disorders that cause substantial morbidity and mortality. In patients with ILD, elevated antinuclear antibody (ANA) titres may be a sign of an autoimmune process. Inhalational exposures contribute to ILD pathogenesis and affect prognosis and may trigger autoimmune disease. The association of inhalational exposures with ANA seropositivity in ILD patients is unknown. Methods This was a retrospective cohort study of adult ILD patients from five centres in the United States. Exposures to tobacco, inhaled organic antigens and inhaled inorganic particles were extracted from medical records. A multivariable logistic regression model was used to analyse the effects of confounders including age, ILD diagnosis, gender and exposure type on ANA seropositivity. Results Among 1265 patients with ILD, there were more ANA-seropositive (58.6%, n=741) than ANA-seronegative patients (41.4%, n=524). ANA-seropositive patients had lower total lung capacity (69% versus 75%, p<0.001) and forced vital capacity (64% versus 70%, p<0.001) than patients who were ANA-seronegative. Among patients with tobacco exposure, 61.4% (n=449) were ANA-positive compared to 54.7% (n=292) of those without tobacco exposure. In multivariable analysis, tobacco exposure remained independently associated with increased ANA seropositivity (OR 1.38, 95% CI 1.12–1.71). This significant difference was similarly demonstrated among patients with and without a history of inorganic exposures (OR 1.52, 95% CI 1.12–2.07). Conclusion Patients with ILD and inhalational exposure had significantly higher prevalence of ANA-seropositivity than those without reported exposures across ILD diagnoses. Environmental and occupational exposures should be systematically reviewed in patients with ILD, particularly those with ANA-seropositivity. Association of antinuclear antibody seropositivity with inhaled exposures in ILDhttps://bit.ly/3AwIPeZ
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Affiliation(s)
- Kathleen Biblowitz
- Division of Pulmonary and Critical Care, Dept of Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - Cathryn Lee
- Section of Pulmonology and Critical Care Medicine, University of Chicago, Chicago, IL, USA
| | - Daisy Zhu
- Pulmonary and Critical Care Medicine, University of Virginia, Charlottesville, VA, USA
| | - Imre Noth
- Pulmonary and Critical Care Medicine, University of Virginia, Charlottesville, VA, USA
| | - Rekha Vij
- Section of Pulmonology and Critical Care Medicine, University of Chicago, Chicago, IL, USA
| | - Mary E Strek
- Section of Pulmonology and Critical Care Medicine, University of Chicago, Chicago, IL, USA
| | - Shashi K Bellam
- Division of Pulmonary and Critical Care, Dept of Medicine, NorthShore University HealthSystem, Evanston, IL, USA
| | - Ayodeji Adegunsoye
- Section of Pulmonology and Critical Care Medicine, University of Chicago, Chicago, IL, USA
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Adegunsoye A, Neborak JM, Zhu D, Cantrill B, Garcia N, Oldham JM, Noth I, Vij R, Kuzniar TJ, Bellam SK, Strek ME, Mokhlesi B. CPAP Adherence, Mortality, and Progression-Free Survival in Interstitial Lung Disease and OSA. Chest 2020; 158:1701-1712. [PMID: 32450237 DOI: 10.1016/j.chest.2020.04.067] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 04/04/2020] [Accepted: 04/09/2020] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND OSA, a common comorbidity in interstitial lung disease (ILD), could contribute to a worsened course if untreated. It is unclear if adherence to CPAP therapy improves outcomes. RESEARCH QUESTION Does adherence to CPAP therapy improve outcomes in patients with concurrent interstitial lung disease and OSA? STUDY DESIGN AND METHODS We conducted a 10-year retrospective observational multicenter cohort study, assessing adult patients with ILD who had undergone polysomnography. Subjects were categorized based on OSA severity into no/mild OSA (apnea-hypopnea index score < 15) or moderate/severe OSA (apnea-hypopnea index score ≥ 15). All subjects prescribed and adherent to CPAP were deemed to have treated OSA. Cox regression models were used to examine the association of OSA severity and CPAP adherence with all-cause mortality risk and progression-free survival (PFS). RESULTS Of 160 subjects that met inclusion criteria, 131 had OSA and were prescribed CPAP. Sixty-six patients (41%) had no/mild untreated OSA, 51 (32%) had moderate/severe untreated OSA, and 43 (27%) had treated OSA. Subjects with no/mild untreated OSA did not differ from those with moderate/severe untreated OSA in mean survival time (127 ± 56 vs 138 ± 93 months, respectively; P = .61) and crude mortality rate (2.9 per 100 person-years vs 2.9 per 100 person-years, respectively; P = .60). Adherence to CPAP was not associated with improvement in all-cause mortality risk (hazard ratio [HR], 1.1; 95% CI, 0.4-2.9; P = .79) or PFS (HR, 0.9; 95% CI, 0.5-1.5; P = .66) compared with those that were nonadherent or untreated. Among subjects requiring supplemental oxygen, those adherent to CPAP had improved PFS (HR, 0.3; 95% CI, 0.1-0.9; P = .03) compared with nonadherent or untreated subjects. INTERPRETATION Neither OSA severity nor adherence to CPAP was associated with improved outcomes in patients with ILD except those requiring supplemental oxygen.
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Affiliation(s)
- Ayodeji Adegunsoye
- Section of Pulmonary & Critical Care, Department of Medicine, The University of Chicago, Chicago, IL.
| | - Julie M Neborak
- Section of Pulmonary & Critical Care, Department of Medicine, The University of Chicago, Chicago, IL; Sleep Disorders Center, Department of Medicine, The University of Chicago, Chicago, IL
| | - Daisy Zhu
- Division of Pulmonary & Critical Care, Department of Medicine, NorthShore University HealthSystem, Evanston, IL
| | - Benjamin Cantrill
- Division of Pulmonary & Critical Care, Department of Medicine, NorthShore University HealthSystem, Evanston, IL
| | - Nicole Garcia
- Section of Pulmonary & Critical Care, Department of Medicine, The University of Chicago, Chicago, IL
| | - Justin M Oldham
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Medicine, University of California at Davis, Davis, CA
| | - Imre Noth
- Pulmonary & Critical Care Medicine, University of Virginia, Charlottesville, VA
| | - Rekha Vij
- Section of Pulmonary & Critical Care, Department of Medicine, The University of Chicago, Chicago, IL
| | - Tomasz J Kuzniar
- Division of Pulmonary & Critical Care, Department of Medicine, NorthShore University HealthSystem, Evanston, IL
| | - Shashi K Bellam
- Division of Pulmonary & Critical Care, Department of Medicine, NorthShore University HealthSystem, Evanston, IL
| | - Mary E Strek
- Section of Pulmonary & Critical Care, Department of Medicine, The University of Chicago, Chicago, IL
| | - Babak Mokhlesi
- Section of Pulmonary & Critical Care, Department of Medicine, The University of Chicago, Chicago, IL; Sleep Disorders Center, Department of Medicine, The University of Chicago, Chicago, IL
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Adegunsoye A, Oldham JM, Bellam SK, Montner S, Churpek MM, Noth I, Vij R, Strek ME, Chung JH. Computed Tomography Honeycombing Identifies a Progressive Fibrotic Phenotype with Increased Mortality across Diverse Interstitial Lung Diseases. Ann Am Thorac Soc 2019; 16:580-588. [PMID: 30653927 PMCID: PMC6491052 DOI: 10.1513/annalsats.201807-443oc] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 01/16/2019] [Indexed: 12/20/2022] Open
Abstract
Rationale: Honeycombing on chest computed tomography (CT) has been described in diverse forms of interstitial lung disease (ILD); however, its prevalence and association with mortality across the spectrum of ILD remains unclear. Objective: To determine the prevalence and prognostic value of CT honeycombing and characterize associated mortality patterns across diverse ILD subtypes in a multicenter cohort. Methods: This was an observational cohort study of adult participants with multidisciplinary or adjudicated ILD diagnosis and documentation of chest CT imaging at index diagnosis across five U.S. hospitals (one tertiary and four nontertiary medical centers). Participants were stratified based on presence or absence of CT honeycombing. Vital status was determined from review of medical records and social security death index. Transplant-free survival was analyzed using univariate and multivariable Cox regression. Results: The sample comprised 1,330 participants (mean age, 66.8 yr; 50% men) with 4,831 person-years of follow-up. The prevalences of CT honeycombing were 42.0%, 41.9%, 37.6%, and 28.6% in chronic hypersensitivity pneumonitis, connective tissue disease-related ILD (CTD-ILD), idiopathic pulmonary fibrosis (IPF), and unclassifiable/other ILDs, respectively. Among those with CT honeycombing, cumulative mortality hazards were similar across ILD subtypes, except for CTD-ILD, which had a lower mortality hazard. Overall, the mean survival time was shorter among those with CT honeycombing (107 mo; 95% confidence interval [CI], 92-122 mo) than those without CT honeycombing (161 mo; 95% CI, 147-174 mo). CT honeycombing was associated with an increased mortality rate (hazard ratio, 1.72; 95% CI, 1.38-2.14) even after adjustment for center, sex, age, forced vital capacity, diffusing capacity, ILD subtype, and use of immunosuppressive therapy (hazard ratio, 1.62; 95% CI, 1.29-2.02). CT honeycombing was associated with an increased mortality rate within non-IPF ILD subgroups (chronic hypersensitivity pneumonitis, CTD-ILD, and unclassifiable/other ILD). In IPF, however, mortality rates were similar between those with and without CT honeycombing. Conclusions: CT honeycombing is prevalent in diverse forms of ILD and uniquely identifies a progressive fibrotic ILD phenotype with a high mortality rate similar to IPF. CT honeycombing did not confer additional risk in IPF, which is already known to be a progressive fibrotic ILD phenotype regardless of the presence of CT honeycombing.
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Affiliation(s)
| | - Justin M. Oldham
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, University of California at Davis, Davis, California
| | - Shashi K. Bellam
- Division of Pulmonary and Critical Care, Department of Medicine, NorthShore University HealthSystem, Evanston, Illinois; and
| | | | - Matthew M. Churpek
- Section of Pulmonary and Critical Care, Department of Medicine
- Department of Public Health Sciences, The University of Chicago, Chicago, Illinois
| | - Imre Noth
- Pulmonary and Critical Care Medicine, University of Virginia, Charlottesville, Virginia
| | - Rekha Vij
- Section of Pulmonary and Critical Care, Department of Medicine
| | - Mary E. Strek
- Section of Pulmonary and Critical Care, Department of Medicine
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Adegunsoye A, Oldham JM, Bellam SK, Chung JH, Chung PA, Biblowitz KM, Montner S, Lee C, Hsu S, Husain AN, Vij R, Mutlu G, Noth I, Churpek MM, Strek ME. African-American race and mortality in interstitial lung disease: a multicentre propensity-matched analysis. Eur Respir J 2018; 51:13993003.00255-2018. [PMID: 29724923 DOI: 10.1183/13993003.00255-2018] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 04/24/2018] [Indexed: 11/05/2022]
Abstract
We studied whether African-American race is associated with younger age and decreased survival time at diagnosis of interstitial lung disease (ILD).We performed a multicentre, propensity score-matched analysis of patients with an ILD diagnosis followed at five US hospitals between 2006 and 2016. African-Americans were matched with patients of other races based on a time-dependent propensity score calculated from multiple patient, physiological, diagnostic and hospital characteristics. Multivariable logistic regression models were used. All-cause mortality and hospitalisations were compared between race-stratified patient cohorts with ILD, and sensitivity analyses were performed.The study included 1640 patients with ILD, 13% of whom were African-American, followed over 5041 person-years. When compared with patients of other races, African-Americans with ILD were younger at diagnosis (56 years versus 67 years), but in the propensity-matched analyses had greater survival (hazard ratio 0.46, 95% CI 0.28-0.77; p=0.003) despite similar risk of respiratory hospitalisations (relative risk 1.04, 95% CI 0.83-1.31; p=0.709), and similar GAP-ILD (gender-age-physiology-ILD) scores at study entry. Sensitivity analyses in a separate cohort of 9503 patients with code-based ILD diagnosis demonstrated a similar association of baseline demographic characteristics with all-cause mortality.We conclude that African-Americans demonstrate a unique phenotype associated with younger age at ILD diagnosis and perhaps longer survival time.
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Affiliation(s)
- Ayodeji Adegunsoye
- Section of Pulmonary and Critical Care, Dept of Medicine, The University of Chicago, Chicago, IL, USA
| | - Justin M Oldham
- Division of Pulmonary, Critical Care and Sleep Medicine, Dept of Medicine, University of California at Davis, Davis, CA, USA
| | - Shashi K Bellam
- Division of Pulmonary and Critical Care, Dept of Medicine, NorthShore University HealthSystem, Evanston, IL, USA
| | | | - Paul A Chung
- Dept of Medicine, NorthShore University HealthSystem, Evanston, IL, USA
| | | | - Steven Montner
- Dept of Radiology, The University of Chicago, Chicago, IL, USA
| | - Cathryn Lee
- Section of Pulmonary and Critical Care, Dept of Medicine, The University of Chicago, Chicago, IL, USA
| | - Scully Hsu
- Section of Pulmonary and Critical Care, Dept of Medicine, The University of Chicago, Chicago, IL, USA
| | - Aliya N Husain
- Dept of Pathology, The University of Chicago, Chicago, IL, USA
| | - Rekha Vij
- Section of Pulmonary and Critical Care, Dept of Medicine, The University of Chicago, Chicago, IL, USA
| | - Gokhan Mutlu
- Section of Pulmonary and Critical Care, Dept of Medicine, The University of Chicago, Chicago, IL, USA
| | - Imre Noth
- Section of Pulmonary and Critical Care, Dept of Medicine, The University of Chicago, Chicago, IL, USA
| | - Matthew M Churpek
- Section of Pulmonary and Critical Care, Dept of Medicine, The University of Chicago, Chicago, IL, USA.,Dept of Public Health Sciences, The University of Chicago, Chicago, IL, USA.,Both authors contributed equally
| | - Mary E Strek
- Section of Pulmonary and Critical Care, Dept of Medicine, The University of Chicago, Chicago, IL, USA.,Both authors contributed equally
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McConville JF, Fernandes DJ, Churchill J, Dewundara S, Kogut P, Shah S, Fuchs G, Kedainis D, Bellam SK, Patel NM, McCauley J, Dulin NO, Gupta MP, Adam S, Yoneda Y, Camoretti-Mercado B, Solway J. Nuclear import of serum response factor in airway smooth muscle. Am J Respir Cell Mol Biol 2010; 45:453-8. [PMID: 21131446 DOI: 10.1165/rcmb.2008-0393oc] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We have previously shown that the transcription-promoting activity of serum response factor (SRF) is partially regulated by its extranuclear redistribution. In this study, we examined the cellular mechanisms that facilitate SRF nuclear entry in canine tracheal smooth muscle cells. We used in vitro pull-down assays to determine which karyopherin proteins bound SRF and found that SRF binds KPNA1 and KPNB1 through its nuclear localization sequence. Immunoprecipitation studies also demonstrated direct SRF-KPNA1 interaction in HEK293 cells. Import assays demonstrated that KPNA1 and KPNB1 together were sufficient to mediate rapid nuclear import of SRF-GFP. Our studies also suggest that SRF is able to gain nuclear entry through an auxiliary, nuclear localization sequence-independent mechanism.
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Affiliation(s)
- John F McConville
- Department of Medicine, University of Chicago, 5841 S. Maryland Avenue, MC6026, Chicago, IL 60637, USA
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