title: Small interfering RNAs targeted to interleukin-4 and respiratory syncytial virus reduce airway inflammation in a mouse model of virus-induced asthma exacerbation.
abstract: Asthma exacerbations are caused primarily by viral infections. Antisense and small interfering RNA (siRNA) technologies have gained attention as potential antiasthma and antiviral approaches. In this study we analyzed whether gene silencing of interleukin (IL)-4 expression and respiratory syncytial virus (RSV) replication by RNA interference is able to suppress allergen- and virus-induced responses in a mouse model of virus-induced asthma exacerbation. Knockdown efficacy of IL-4 siRNA molecules was analyzed in the human HEK293T cell line by cotransfection of six different siRNAs with a plasmid carrying mouse IL-4. The most potent siRNA was then used in a mouse model of RSV-induced asthma exacerbation. BALB/c mice were sensitized intraperitoneally with ovalbumin (OVA) and then infected 12 days later intranasally with RSV Long strain (1×10(6) TCID50/mouse), followed 1 day later by intranasal challenge with OVA for 3 days. Mice were pretreated intranasally three times with either siRNA to IL-4 or GFP control, 2 days before, and on the first two OVA challenge days. siRNAs to RSV or rhinovirus control were inoculated intranasally once, 3 hr before RSV infection. Combined anti-IL-4 and anti-RSV siRNAs were able to significantly reduce total cell counts and eosinophilia in bronchoalveolar lavage fluid, development of airway hyperresponsiveness, and airway inflammation and to downregulate IL-4 mRNA expression and RSV viral RNA, but to upregulate IFN-γ levels in lung tissues. We conclude that anti-helper T cells type 2 and antiviral siRNAs may constitute a new therapeutic approach for treatment of virus induced asthma exacerbations.
authors.affiliation: 1 National Research Center Institute of Immunology of Federal Medicobiological Agency , Moscow 115478, Russia .
authors.forename: Musa R
authors.initials: MR
authors.lastname: Khaitov
authors.forename: Igor P
authors.initials: IP
authors.lastname: Shilovskiy
authors.forename: Aleksandra A
authors.initials: AA
authors.lastname: Nikonova
authors.forename: Nadezda N
authors.initials: NN
authors.lastname: Shershakova
authors.forename: Oleg Y
authors.initials: OY
authors.lastname: Kamyshnikov
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Babakhin
authors.forename: Vitaly V
authors.initials: VV
authors.lastname: Zverev
authors.forename: Sebastian L
authors.initials: SL
authors.lastname: Johnston
authors.forename: Rakhim M
authors.initials: RM
authors.lastname: Khaitov
mesh_terms: D000818:Animals; D001249:Asthma / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000628:therapy; D001992:Bronchoalveolar Lavage Fluid; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D007249:Inflammation; D015847:Interleukin-4 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D034741:RNA, Small Interfering / Q000235:genetics / Q000494:pharmacology; D012367:RNA, Viral / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology; D018357:Respiratory Syncytial Virus Infections / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000628:therapy; D012136:Respiratory Syncytial Viruses / Q000235:genetics / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology / Q000473:pathology
chemical_list: D034741:RNA, Small Interfering; D012367:RNA, Viral; D015847:Interleukin-4