Journal: Disease Models & Mechanisms

Article Title: The anti-fibrotic effect of inhibition of TGFβ-ALK5 signalling in experimental pulmonary fibrosis in mice is attenuated in the presence of concurrent γ-herpesvirus infection

doi: 10.1242/dmm.019984

Figure Lengend Snippet: The anti-fibrotic effect of TGFβ-ALK5 signalling inhibition is attenuated in the two-hit model of MHV-68 infection on the background of pre-existing fibrosis. Total lung collagen was quantified by reverse-phase HPLC 28 days post-oropharyngeal bleomycin instillation (corresponding to 14 days p.i. with MHV-68). The ALK5 inhibitor SB525334 was administered according to a therapeutic dosing regimen during the progressive fibrotic phase (from day 15 post-bleomycin-instillation; corresponding to 1 day p.i.). MHV-68 infection in saline control lung did not significantly increase lung collagen levels. SB525334 attenuated lung collagen accumulation in the single-hit model of lung fibrosis, but the anti-fibrotic effect of SB525334 was attenuated in the two-hit model of fibrosis with concomitant infection of fibrotic lung. Data are representative of mean±s.e.m., n =3 for saline groups and n =8 for bleomycin groups; statistical analysis, Student’s t -test, * P <0.05.

Article Snippet: The highly selective ALK5 inhibitor SB525334 ( ) was a kind gift from Novartis, Horsham, UK.

Techniques: Inhibition, Infection, Saline, Control

Journal: Disease Models & Mechanisms

Article Title: The anti-fibrotic effect of inhibition of TGFβ-ALK5 signalling in experimental pulmonary fibrosis in mice is attenuated in the presence of concurrent γ-herpesvirus infection

doi: 10.1242/dmm.019984

Figure Lengend Snippet: μCT characterization and quantification of the pathological changes in the single- and two-hit models. 3D volume reconstruction (left panels, dorsal view) and representative coronal µCT sections (middle panels) with higher (4×) magnification of the highlighted insert (right panel). Mice treated with saline (Sal; A) or Sal+MHV-68 (B) show normal lung morphology; Bleomycin (Bleo)-treated mice (C) show dense subpleural fibrotic lesions, which are attenuated in the Bleo+SB525334 group (D); Bleo+MHV-68 mice (E) show evidence of extensive ground-glass opacities radiating from airways and overlying areas of dense consolidation; Bleo+MHV-68+SB525334 mice (F) reveal dense consolidation with reduced areas of ground-glass opacities. InForm analysis demonstrates an increase in the percentage of abnormal lung area (G) and density (H) in Bleo lungs above the Sal control (dotted line). No significant difference was observed between the Bleo and Bleo+MHV-68 groups. Administration of SB525334 from day 15 post-bleomycin-instillation (and 1 day p.i.) significantly attenuated lung pathology in the Bleo group but not in the two-hit Bleo+MHV-68 model. The data are representative of mean±s.e.m., one-way ANOVA, * P <0.05, ** P <0.01, comparison of all Bleo-challenged groups ( n =5).

Article Snippet: The highly selective ALK5 inhibitor SB525334 ( ) was a kind gift from Novartis, Horsham, UK.

Techniques: Saline, Control, Comparison

Journal: Disease Models & Mechanisms

Article Title: The anti-fibrotic effect of inhibition of TGFβ-ALK5 signalling in experimental pulmonary fibrosis in mice is attenuated in the presence of concurrent γ-herpesvirus infection

doi: 10.1242/dmm.019984

Figure Lengend Snippet: Voxel density distribution analysis shows key differences between the single- and two-hit models. Density distribution histograms show the mean number of voxels plotted against greyscale density values (0=air/black, 255=dense tissue/white) for each experimental group. (A) A shift towards higher voxel densities is observed for bleomycin (Bleo)-treated lungs due to Bleo-induced injury, and a further shift to the right for the two-hit Bleo+MHV-68 group is indicative of additional injury. This density shift is reduced in the Bleo+SB525334 group, suggestive of attenuated fibrosis but not in Bleo+MHV-68+SB525334 lungs. (B) The differences in proportion of density voxels for each greyscale bin between Bleo-instilled groups ( n =5 animals per group), which account for the shifts in the histograms, were analyzed by Student’s t -test at each bin. The data are shown as graphs of probability ( y -axis) versus greyscale density value ( x -axis), with the significance cut-off set at 0.05 (indicated by the dotted line). (C-E) Distribution of significantly different voxel densities was visualized on representative µCT scans (red pixels): (C) Bleo and Bleo+SB525334 show voxel localization to fibrotic lesions; (D) Bleo+MHV-68 and Bleo lungs show voxel distribution in fibrotic lesions and dispersed throughout the parenchyma; (E) Bleo+MHV-68 and Bleo+MHV-68+SB525334 lungs show voxel distribution dispersed throughout the parenchyma.

Article Snippet: The highly selective ALK5 inhibitor SB525334 ( ) was a kind gift from Novartis, Horsham, UK.

Techniques:

Journal: Disease Models & Mechanisms

Article Title: The anti-fibrotic effect of inhibition of TGFβ-ALK5 signalling in experimental pulmonary fibrosis in mice is attenuated in the presence of concurrent γ-herpesvirus infection

doi: 10.1242/dmm.019984

Figure Lengend Snippet: Histological analysis of the single- and two-hit models. Representative H&E and MSB sections (100× original magnification; scale bars: 600 μm) are shown for each experimental group as annotated. Saline (Sal) and Saline+MHV-68 lungs show normal morphology (A,B); (C) typical examples of the fibrotic lesions with evidence of collagen deposition observed in the Bleo group. These are greatly reduced in Bleo+SB525334 lungs (D); Bleo+MHV-68 lungs show extensive fibrotic lesions with collagen deposition and dense inflammatory cell aggregates that appear less frequent and more dispersed in Bleo+MHV-68+SB525334 lungs (E,F, boxed area is 200× magnification; scale bars: =300 μm). FB, fibrosis; COL, collagen; IA, inflammatory cell aggregates.

Article Snippet: The highly selective ALK5 inhibitor SB525334 ( ) was a kind gift from Novartis, Horsham, UK.

Techniques: Saline

Journal: Disease Models & Mechanisms

Article Title: The anti-fibrotic effect of inhibition of TGFβ-ALK5 signalling in experimental pulmonary fibrosis in mice is attenuated in the presence of concurrent γ-herpesvirus infection

doi: 10.1242/dmm.019984

Figure Lengend Snippet: ALK5 inhibition attenuates inflammatory cell aggregates and enhances IFNγ levels in the two-hit model of MHV-68 infection on a background of pulmonary fibrosis. (A) Inflammatory aggregates (IAs) were significantly increased in bleomycin- and MHV-68-injured lungs when compared to other bleomycin-challenged groups ( n =5). SB525334 treatment reduced the number of IAs, quantified and expressed as region of interest per lung (ROI/mm 2 , mean±s.e.m., five tissue sections per mouse). Levels of inflammatory and immunomodulatory markers were measured in lung homogenates: CCL2 (B), IFNγ (C), IL-1β (D), TNFα (E), IL-10 (F); representative of mean±s.e.m., n =3 for saline groups and n =8 for bleomycin groups. One-way ANOVA, * P <0.05, ** P <0.01, *** P <0.001.

Article Snippet: The highly selective ALK5 inhibitor SB525334 ( ) was a kind gift from Novartis, Horsham, UK.

Techniques: Inhibition, Infection, Saline