Figure 8. Macrophages harvested from bleomycin challenged mice can regulate the profibrotic effector functions of fibroblasts.
Fibroblasts were cultured from previously unchallenged WT mice. Lung macrophages were collected from WT and IRAK-M−/− mice that were either unchallenged or day 14 post-bleomycin challenge. CD45+ cells were isolated from lung macrophages and total numbers of macrophages were quantified by modified Wright-giemsa stain. A. and B. Approximately 1 × 106 total macrophages were co-cultured with 5 × 105 WT fibroblasts. The expression of αSMA (A) and collagen III (B) were measured by realtime RT-PCR. C. Cell free supernatants were harvested from macrophages isolated from bleomycin challenged and cultured with WT unchallenged fibroblasts. The expression of collagen III was measure by realtime RT-PCR. D. Lung macrophages from unchallenged or bleomycin challenged mice were incubated with either control IgG or anti-IL-13 neutralizing antibody (2 µg/ml). The expression of pro-fibrotic mediators were measured after 48 h in culture by realtime RT-PCR (D). Graphs represent mean ± SEM with n=4 samples/group from 2 separate experiments. *p<0.05, **p<0.01, ***p<0.001 when compared to fibroblasts from WT unchallenged mice.