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. 2010 May;3(3):291-300.
doi: 10.1038/mi.2010.6. Epub 2010 Mar 10.

Control of RSV-induced lung injury by alternatively activated macrophages is IL-4R alpha-, TLR4-, and IFN-beta-dependent

K A Shirey  1 , L M Pletneva, A C Puche, A D Keegan, G A Prince, J C G Blanco, S N Vogel
Affiliations

Control of RSV-induced lung injury by alternatively activated macrophages is IL-4R alpha-, TLR4-, and IFN-beta-dependent

K A Shirey et al. Mucosal Immunol. 2010 May.

Abstract

Severe respiratory syncytial virus (RSV)-induced bronchiolitis has been associated with a mixed "Th1" and "Th2" cytokine storm. We hypothesized that differentiation of "alternatively activated" macrophages (AA-M phi) would mediate the resolution of RSV-induced lung injury. RSV induced interleukin (IL)-4 and IL-13 by murine lung and peritoneal macrophages, IL-4R alpha/STAT6-dependent AA-M phi differentiation, and significantly enhanced inflammation in the lungs of IL-4R alpha(-/-) mice. Adoptive transfer of wildtype macrophages to IL-4R alpha(-/-) mice restored RSV-inducible AA-M phi phenotype and diminished lung pathology. RSV-infected Toll-like receptor (TLR)4(-/-) and interferon (IFN)-beta(-/-) macrophages and mice also failed to express AA-M phi markers, but exhibited sustained proinflammatory cytokine production (e.g., IL-12) in vitro and in vivo and epithelial damage in vivo. TLR4 signaling is required for peroxisome proliferator-activated receptor gamma expression, a DNA-binding protein that induces AA-M phi genes, whereas IFN-beta regulates IL-4, IL-13, IL-4R alpha, and IL-10 expression in response to RSV. RSV-infected cotton rats treated with a cyclooxygenase-2 inhibitor increased expression of lung AA-M phi. These data suggest new treatment strategies for RSV that promote AA-M phi differentiation.

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Figures

Fig. 1
Fig. 1. RSV infection induces differentiation of AA-Mϕ
(A) Highly purified WT BALB/c BAL macrophage cultures were treated with medium only or infected with RSV. Supernatants were collected at the indicated time points and analyzed for IL-4 and IL-13 by ELISA. (B) WT BALB/c BAL macrophages were treated with medium alone, rIL-4, or RSV. Gene expression was analyzed by real-time PCR. Data are means ± SEM from a single representative experiment (N = 4). (C) WT C57BL/6 mice were mock- or RSV-infected and lungs harvested 4 d p.i. Frozen lung sections were stained for nuclei (DAPI; blue), F4/80 (green), and arginase-1 (red), then viewed by confocal microscopy. Arrows are positioned identically on each panel within a treatment to provide a reference point. The arrowhead in panels f–j illustrates a rare cell that is positive for F4/80, but not for arginase-1.
Fig. 2
Fig. 2. Failure to induce AA-Mϕ prolongs CA-Mϕ phenotype
(A) WT BALB/c and IL-4Rα−/− peritoneal macrophages were treated as in Fig. 1 and mRNA expression measured. Data are derived from a single representative experiment (N = 3). (B) WT and IL-4Rα−/− mice were mock- or RSV-infected. Mice were sacrificed 4 d p.i., and arginase-1 and IL-12 p40 mRNA measured in lungs by real-time PCR. (C) WT and IL-4Rα−/− mice were treated as in (B). Lung pathology was scored as described in Methods. Results are compiled from 3 independent experiments. (D) WT and IL-4Rα−/− mice were mock- or RSV-infected. Lungs were harvested 4 d p.i. Lung pathology was scored (N = 4; 4 mice/treatment). Images shown are at 100x.
Fig. 3
Fig. 3. Adoptive transfer of WT macrophages reconstitutes AA-Mϕ phenotype in IL-4Rα−/− mice
(A) WT BALB/c and IL-4Rα−/− mice, along with IL-4Rα−/− mice that received either 1.5 × 107 WT (WT→IL-4Rα−/−) or IL-4Rα−/− (IL-4Rα−/−→IL-4Rα−/−) macrophages i.p., were mock- or RSV-infected 5 d post-transfer. Lungs were harvested 4 d p.i. and analyzed for gene expression by real-time PCR. (B) Lung sections from mice in (A) were H&E stained and scored for lung pathology. Data represent one of 2 separate experiments with similar outcomes (10 mice/treatment).
Fig. 4
Fig. 4. Differentiation of AA-Mϕ by RSV is TLR4-dependent
(A) WT C57BL/6 and TLR4−/− peritoneal macrophages were treated as indicated in Fig. 1 and analyzed for mRNA gene expression by real-time PCR (N = 3). (B) WT and TLR4−/− macrophages were treated as in (A) and analyzed for PPARγ mRNA gene expression by real-time PCR. (C) WT and TLR4−/− mice were mock- or RSV-infected. Lungs were harvested 4 d p.i. Lung pathology was scored (N = 4; 4 mice/treatment). Images shown are at 200x.
Fig. 5
Fig. 5. RSV-induced AA-Mϕ and IL-10 production are IFN-β-dependent
(A) WT and IFN-β−/− peritoneal macrophages were treated as indicated and analyzed for mRNA by real-time PCR (N = 2). (B) WT or IFN-β−/− mice were mock- or RSV-infected. At 4 d p.i., mice were sacrificed and lungs analyzed for arginase-1, FIZZ1, and MR mRNA. (C) IL-10 and COX-2 mRNA were measured in the lungs of RSV-infected mice (see legend to (B)). (C) Mice were infected as in (B) and lungs fixed and stained with H&E 4 d p.i. (N = 4; 4 mice/treatment). Images shown are at 400x.
Fig. 6
Fig. 6. Rapid activation of AA-Mϕ in cotton rats during re-infection and in response to COX-2 inhibition
(A) Cotton rats (4/group) were administered saline or infected with RSV. Animals were then RSV-infected 60 d after initial treatment. Lungs were harvested, total RNA isolated, and analyzed for IL-4, IL-13, and arginase-1 mRNA by RT-PCR and Southern blotting. (B) Cotton rats were mock- or RSV-infected. Infected rats were treated on day 3 p.i. with vehicle (saline) or paracoxib (100 mg/kg) i.p. All animals were sacrificed 4 d p.i. and lung samples evaluated for mRNA expression for the indicated genes. Each lane represents RNA from one cotton rat and results are representative of 3 separate experiments.
Fig. 7
Fig. 7. Hypothetical model for the role of AA-Mϕ during RSV infection
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References

    1. Welliver RC. Review of epidemiology and clinical risk factors for severe respiratory syncytial virus (RSV) infection. J. Pediatr. 2003;143:S112–S117. - PubMed
    1. Blanco JCG, Boukhvalova M, Pletneva L, Prince GA, Vogel SN. Rethinking respiratory syncytial virus vaccines. Recent Res. Devel. Experimental Med. 2004;1:75–94. Appendix 1.
    1. Boukhvalova MS, Prince GA, Soroush L, Harrigan DC, Vogel SN, Blanco JC. The TLR4 agonist, monophosphoryl lipid A, attenuates the cytokine storm associated with respiratory syncytial virus vaccine-enhanced disease. Vaccine. 2006;24:5027–5035. - PubMed
    1. Pletneva LM, Haller O, Porter DD, Prince GA, Blanco JC. Interferon-inducible Mx gene expression in cotton rats: cloning, characterization, and expression during influenza viral infection. J. Interferon Cytokine Res. 2006;26:914–921. - PubMed
    1. Kurt-Jones EA, et al. Pattern recognition receptors TLR4 and CD14 mediate response to respiratory syncytial virus. Nat. Immunol. 2000;1:398–401. - PubMed

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