Scientific Publications by FDA Staff
Clin Exp Immunol 2007 May;148(2):218-29
Respiratory syncytial virus replication is prolonged by a concomitant allergic response.
Hassantoufighi A, Oglesbee M, Richter BW, Prince GA, Hemming V, Niewiesk S, Eichelberger MC
Eichelberger MC (reprint author), US FDA, Ctr Biol Evaluat & Res, Div Viral Prod, Bldg 29B Room 1 N N-15,8800 Rockville Pike, Rockville, MD 20852 USA Virion Syst Inc, Rockville, MD USA Ohio State Univ, Dept Vet Biosci, Columbus, OH USA
Epidemiological studies show an association between early exposure to respiratory syncytial virus (RSV) and the development or exacerbation of asthma. This idea is supported by studies in mice that demonstrate worsened airway hyper-reactivity (AHR) when RSV-infected animals are exposed to allergen. The effect of allergen on RSV disease, however, has not been reported. Cotton rats (Sigmodon hispidus) that have been used as a model to study RSV pathogenesis were sensitized to extracts of Aspergillus fumigatus (Af), a common household mould. The allergic response to Af included eosinophilia, formation of granulomas and induction of Th2 type cytokines. RSV infection prior to allergen challenge resulted in exacerbation of the inflammatory response as well as increased airway responsiveness to methacholine. The exacerbated response was indeed dependent on virus replication. Virus replication in turn was influenced by the allergic response, with persistence in the noses for 2 days longer in animals challenged with allergen. This diminished clearance corresponded to decreased induction of mRNA for IFN-gamma, a Th1-type cytokine that is characteristic of viral infection. Treatment of RSV-infected Af-challenged animals with recombinant IFN-gamma reduced the allergic inflammatory response as well as the relative levels of Th1 and Th2 cytokine mRNA. However, this treatment did not reduce airway reactivity, showing that these pathologic and physiologic measures of exacerbated disease are independent. We speculate that the reciprocal effect of the allergic response on viral immunity may benefit the host by limiting exacerbation of physiologic responses that are IFN-gamma-dependent.
|Category: Journal Article|
|PubMed ID: #17335559|
|Includes FDA Authors from Scientific Area(s): Biologics|
|Entry Created: 2011-10-04||Entry Last Modified: 2012-08-29|