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1.  RIG-like Helicase Innate Immunity Inhibits Vascular Endothelial Growth Factor Tissue Responses via a Type I IFN–dependent Mechanism 
Rationale: Vascular endothelial growth factor (VEGF) regulates vascular, inflammatory, remodeling, and cell death responses. It plays a critical role in normal pulmonary physiology, and VEGF excess and deficiency have been implicated in the pathogenesis of asthma and chronic obstructive pulmonary disease, respectively. Although viruses are an important cause of chronic obstructive pulmonary disease exacerbations and innate responses play an important role in these exacerbations, the effects of antiviral responses on VEGF homeostasis have not been evaluated.
Objectives: We hypothesized that antiviral innate immunity regulates VEGF tissue responses.
Methods: We compared the effects of transgenic VEGF165 in mice treated with viral pathogen–associated molecular pattern polyinosinic:polycytidylic acid [poly(I:C)], mice treated with live virus, and control mice.
Measurements and Main Results: Transgenic VEGF stimulated angiogenesis, edema, inflammation, and mucin accumulation. Each of these was abrogated by poly(I:C). These inhibitory effects were dose dependent, noted when poly(I:C) was administered before and after transgene activation, and mediated by a Toll-like receptor-3–independent and RIG-like helicase (RLH)– and type I IFN receptor–dependent pathway. VEGF stimulated the expression of VEGF receptor-1 and poly(I:C) inhibited this stimulation. Poly(I:C) also inhibited the ability of VEGF to activate extracellular signal–regulated kinase-1, Akt, focal adhesion kinase, and endothelial nitric oxide synthase, and aeroallergen-induced adaptive helper T-cell type 2 inflammation. Influenza and respiratory syncytial virus also inhibited VEGF-induced angiogenesis.
Conclusions: These studies demonstrate that poly(I:C) and respiratory viruses inhibit VEGF-induced tissue responses and adaptive helper T-cell type 2 inflammation and highlight the importance of a RLH- and type I IFN receptor–dependent pathway(s) in these regulatory events. They define a novel link between VEGF and antiviral and RLH innate immune responses and a novel pathway that regulates pulmonary VEGF activity.
PMCID: PMC3114061  PMID: 21278304
RIG-like helicase; mitochondrial antiviral signaling molecule; influenza virus; chronic obstructive pulmonary disease
2.  Tissue inhibitor of metalloproteinase-1 modulates allergic lung inflammation in murine asthma 
Clinical immunology (Orlando, Fla.)  2008;130(2):186-198.
Matrix metalloproteinases (MMPs) modulate development, inflammation, and repair in lungs. Tissue inhibitors of MMPs (TIMPs) interact with MMPs, controlling the intensity and nature of the response to injury. Absence of MMP-9, -2, and -8 activities is associated with altered lung inflammation during allergic sensitization. To test the hypothesis that the absence of TIMP-1 enhances allergic lung inflammation, airway hyperreactivity (AHR), and lung remodeling in asthma, we studied TIMP-1 null (TIMP-1 KO) mice and their WT controls using an ovalbumin (OVA) asthma model. TIMP-1 KO mice, compared to WT controls, developed an asthma phenotype characterized by AHR, pronounced cellular lung infiltrates, greater reduction in lung compliance, enhanced Th2 cytokine mRNA and protein expression, and altered collagen lung content associated with enhanced MMP-9 activity. Our findings support the hypothesis that TIMP-1 plays a protective role by preventing AHR and modulating inflammation, remodeling, and cytokine expression in an animal model of asthma.
PMCID: PMC2676334  PMID: 18955015
Asthma; Bronchial hyperreactivity; TIMP-1; MMPs; Airway remodeling; Intercellular matrix

Results 1-2 (2)