Chronic inflammation, hypertrophy and squamous metaplasia of the normal, pseudostratified columnar epithelium within the sinuses is a consistent feature of chronic sinusitis, and it is the central premise of this program application that alterations in epithelial cell function may contribute to the pathophysiology of this disease. This project will examine the hypothesis that viral infection of the epithelium plays an important role in the development or exacerbation of chronic sinusitis by triggering alterations in epithelial cell function, particularly increased production of proinflammatory cytokines. To examine the link between viral infection and sinusitis, we will prospectively monitor subjects who have undergone sinus surgery. We will collect nasal and sinus lavages from subjects during periods when their disease is quiescent and as soon as possible after they report exacerbations of their sinusitis. We will use both PCR and standard culture methods for a range of common respiratory viruses to determine the incidence of viral infection in these samples and to correlate the presence of infections with disease exacerbations and with alterations in nasal potential difference (Project 3). Our preliminary data clearly show that rhinovirus infection of epithelial cells in vitro leads to increased release of cytokines. Treatment of cells with glucocorticoids can inhibit virally-induced cytokine production. We will use cultured cells to determine the molecular mechanisms by which viral infection and glucocorticoids regulate epithelial cell cytokine production. We will use Northern blot analysis, nuclear run-on experiments, and cells transfected with promoter constructs to determine if cytokine production is regulated at the transcriptional or posttranscriptional level. The role of NF-kappaB and AP-1 transcriptional regulation sites in the control of epithelial cytokine production by viruses and glucocorticoids will also be examined. To determine if these changes in epithelial cell cytokine production may occur, and play a role in exacerbations of sinusitis, in vivo, we will monitor levels of the epithelial cytokines, IL-8, IL-6 and GM-CSF, in nasal and sinus lavages obtained from our patient populations during periods when their disease is quiescent and during exacerbations. In addition, we will use immunocytochemistry and in situ hybridization to examine sinus biopsies from a subpopulation of subjects to confirm the cellular origin of these cytokines. We will also determine if patients receiving glucocortocoids show a lower incidence of disease exacerbations during viral infections, and will relate any such differences to epithelial cytokine production in vivo and to predisposing factors in our population, such as atopic status, immune competence, or asthmatic status. These studies should provide important insights into the pathogenesis of sinusitis and may lead to the development of improved therapies for the treatment of this major health problem. Our studies on viral alterations of epithelial cell function may also have broader implications of relevance to the pathogenesis of asthma and the common cold.

Project Start
1998-09-01
Project End
1999-08-31
Budget Start
1997-10-01
Budget End
1998-09-30
Support Year
4
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Johns Hopkins University
Department
Type
DUNS #
045911138
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Cruz, Alvaro A; Naclerio, Robert M; Proud, David et al. (2006) Epithelial shedding is associated with nasal reactions to cold, dry air. J Allergy Clin Immunol 117:1351-8
Sanders, Scherer P; Proud, David; Permutt, Solbert et al. (2004) Role of nasal nitric oxide in the resolution of experimental rhinovirus infection. J Allergy Clin Immunol 113:697-702
Subauste, M C; Proud, D (2001) Effects of tumor necrosis factor-alpha, epidermal growth factor and transforming growth factor-alpha on interleukin-8 production by, and human rhinovirus replication in, bronchial epithelial cells. Int Immunopharmacol 1:1229-34
Sanders, S P; Kim, J; Connolly, K R et al. (2001) Nitric oxide inhibits rhinovirus-induced granulocyte macrophage colony-stimulating factor production in bronchial epithelial cells. Am J Respir Cell Mol Biol 24:317-25
Sanders, S P; Siekierski, E S; Richards, S M et al. (2001) Rhinovirus infection induces expression of type 2 nitric oxide synthase in human respiratory epithelial cells in vitro and in vivo. J Allergy Clin Immunol 107:235-43
Kim, J; Sanders, S P; Siekierski, E S et al. (2000) Role of NF-kappa B in cytokine production induced from human airway epithelial cells by rhinovirus infection. J Immunol 165:3384-92
Kidney, J C; Proud, D (2000) Neutrophil transmigration across human airway epithelial monolayers: mechanisms and dependence on electrical resistance. Am J Respir Cell Mol Biol 23:389-95
Togias, A (1999) Mechanisms of nose-lung interaction. Allergy 54 Suppl 57:94-105
Rhyoo, C; Sanders, S P; Leopold, D A et al. (1999) Sinus mucosal IL-8 gene expression in chronic rhinosinusitis. J Allergy Clin Immunol 103:395-400
Sanders, S P; Siekierski, E S; Porter, J D et al. (1998) Nitric oxide inhibits rhinovirus-induced cytokine production and viral replication in a human respiratory epithelial cell line. J Virol 72:934-42

Showing the most recent 10 out of 12 publications