Blockade of airway inflammation and hyperresponsiveness by HIV-TAT-dominant negative Ras.
We have reported previously that HIV-TAT-dominant negative (dn) Ras inhibits eosinophil adhesion to ICAM-1 after activation by IL-5 and eotaxin. In this study, we evaluated the role of Ras in Ag-induced airway inflammation and hyperresponsiveness by i.p. administration into mice of dnRas, which was fused to an HIV-TAT protein transduction domain (TAT-dnRas). Uptake of TAT-dnRas (t(1/2) = 12 h) was demonstrated in leukocytes after i.p. administration. OVA-sensitization significantly increased eosinophil and lymphocyte numbers in bronchoalveolar lavage fluid 24 h after final challenge. Treatment of animals with 3-10 mg/kg TAT-dnRas blocked the migration of eosinophils from 464 +/- 91 x 10(3)/ml to 288 +/- 79 x 10(3)/ml with 3 mg/kg of TAT-dnRas (p < 0.05), and further decreased to 116 +/- 63 x 10(3)/ml after 10 mg/kg TAT-dnRas (p < 0.01). Histological examination demonstrated that inflammatory cell infiltration (largely eosinophils and mononuclear cells) and mucin production around the airways caused by OVA were blocked by TAT-dnRas. OVA challenge also caused airway hyperresponsiveness to methacholine, which was dose dependently blocked by treatment with TAT-dnRas. TAT-dnRas also blocked Ag-induced IL-4 and IL-5, but not IFN-gamma, production in lung tissue. Intranasal administration of IL-5 caused eosinophil migration into the airway lumen, which was attenuated by pretreatment with TAT-dnRas. By contrast, TAT-green fluorescent protein or dnRas lacking the TAT protein transduction domain did not block airway inflammation, cytokine production, or airway hyperresponsiveness. We conclude that Ras mediates Th2 cytokine production, airway inflammation, and airway hyperresponsiveness in immune-sensitized mice.
Myou
Shigeharu
S
Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, IL 60637-1470, USA.
Zhu
Xiangdong
X
Myo
Saori
S
Boetticher
Evan
E
Meliton
Angelo Y
AY
Liu
Jie
J
Munoz
Nilda M
NM
Leff
Alan R
AR
D000281:Administration, Intranasal; D000818:Animals; D000941:Antigens / Q000008:administration & dosage / Q000276:immunology; D016535:Bronchial Hyperreactivity / Q000276:immunology* / Q000473:pathology / Q000517:prevention & control*; D002464:Cell Migration Inhibition; D016207:Cytokines / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D004804:Eosinophils / Q000276:immunology / Q000473:pathology; D015696:Gene Products, tat / Q000008:administration & dosage* / Q000235:genetics; D006678:HIV / Q000235:genetics / Q000276:immunology*; D006801:Humans; D018836:Inflammation Mediators / Q000008:administration & dosage*; D007274:Injections, Intraperitoneal; D015848:Interleukin-5 / Q000008:administration & dosage; D007700:Kinetics; D008168:Lung / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D008214:Lymphocytes / Q000276:immunology / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009093:Mucus / Q000378:metabolism; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage* / Q000235:genetics; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism; D014161:Transduction, Genetic; D018631:ras Proteins / Q000008:administration & dosage* / Q000235:genetics; D054322:tat Gene Products, Human Immunodeficiency Virus
D000941:Antigens; D016207:Cytokines; D015696:Gene Products, tat; D018836:Inflammation Mediators; D015848:Interleukin-5; D011993:Recombinant Fusion Proteins; D054322:tat Gene Products, Human Immunodeficiency Virus; D010047:Ovalbumin; D018631:ras Proteins