Umadevi Sajjan, PhD
Associate Professor, Physiology
Associate Professor, Center for Inflammation, Translational and Clinical Lung Research
Associate Professor, Thoracic Medicine and Surgery
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- About Me
My research interests are centered over understanding the mechanisms underlying defective innate immune responses of airway mucosa to respiratory pathogens and its impact on progression of lung disease in patients with chronic obstructive pulmonary disease (COPD) and cystic fibrosis (CF). Respiratory infections are the major causes of acute exacerbations which often lead to progression of lung disease in this patient population. Rhinovirus, a common cold virus, not only exacerbates lung disease in COPD, but is also thought to increase susceptibility to secondary bacterial infections, indicating that rhinovirus may affect the innate/adaptive immunity in these patients. Our laboratory is interested in understanding the mechanisms by which rhinovirus suppress innate immune responses of airway mucosa and innate immune cells to bacterial infections. In a mouse model of COPD, rhinovirus increases lung inflammation, causes accumulation of macrophages and lymphocytes, promotes development of goblet cell hyperplasia and suppresses innate immune responses to subsequent bacterial infections. We are beginning to understand the molecular mechanisms underlying rhinovirus induced goblet cell metaplasia and suppression of lung innate immunity.
Another area of research that we are actively pursuing is to determine the effects of quercetin, a plant polyphenol, in reducing lung inflammation and improve innate immunity in COPD patients. We have demonstrated that quercetin reduces lung inflammation and airway remodeling in a mouse model of severe COPD. Quercetin was also found to inhibit rhinovirus replication in vitro and rhinovirus-induced lung inflammation in vivo. We are now interested in understanding the mechanisms by which quercetin reduces lung inflammation and improves innate immunity in COPD. We also conducted preliminary clinical trials to show that quercetin is safely tolerated in COPD patients. We are planning to conduct Phase II clinical trials to examine the efficacy of quercetin in reducing lung inflammation and improve quality of health in COPD patients.
Sajjan, U.S., Newcomb, D.C., Lewis, T.C., Stahle, C.S., Hershenson, M.B. Interactions of Respiratory Viruses with the Epithelium. In: The Pulmonary Epithelium, J. Wiley and Sons, West Sussex, UK, 2008, Ch 12, 225-251.
Ganesan S, Sajjan U. Innate Immune responses of COPD airway epithelium. In: Emphysema InTech, Croatia. 2011, Ch 2, 19-48.
Ganesan S, Sajjan US. Host evasion by Burkholderia cenocepacia. Front Cell Infect Micobiol 2011; 1: 25.
Sajjan US. Susceptibility to viral infections in COPD: Role of epithelial cells. Curr. Opi. Pulm. Med. 2012, 19:125-32
Ganesan S, Comstock AT, and Sajjan U Barrier function of airway tract epithelium. Tissue Barriers 2013 Oct 1;1(4):e24997.
Ganesan S, and Sajjan U Airway epithelial repair and remodeling in COPD Curr. Rep Respir Care 2013 Sep 1;2(3). doi: 10.1007/s13665-013-0052-2.
Kinker B, Comstock AT and Sajjan US Quercetin: A Promising Treatment for the Common Cold. 2014 J Anc Dis Prev Rem 2014, 2:2 http://dx.doi.org/10.4172/2329-8731.1000111