TRAIL-Dependent Resolution of Pulmonary Fibrosis

Figure 3

Adoptive transfer of Gr-1⁺ myeloid cells reduced lung fibrosis. Gr-1⁺ cells were purified from the lungs of bleomycin-challenged D−1 Clod Lipo-treated mice at day 5 after bleomycin. (a) Purified Gr-1⁺ myeloid cells from lung were spun onto a slide using a cytospin and stained, and a morphologic analysis was performed using light microscopy (left panel; 1000x magnification). Both lung- and bone marrow-purified CD11b⁺Gr-1⁺ and CD11b⁺Gr-1⁻ myeloid cells were stained for CD80, CD86, MHCII, CD62L, and F4/80 for flow cytometry analysis. (b) Quantitative PCR analysis of RNA isolated from Gr-1⁺ myeloid cells was used to determine transcript levels of arginase, NOS2, IDO, and IL-10. (c) Purified Gr-1⁺ myeloid cells were adoptively transferred into the lungs of bleomycin-challenged mice at days 5 (D+5) or 14 (D+14) after bleomycin. Lung samples were removed at day 21 after bleomycin. Lungs were fixed, paraffin-embedded, sectioned, and stained with Masson’s trichrome. Shown are representative images taken at 100x magnification. (d) Procollagen 3 and fibronectin 1 expression were determined by quantitative PCR using RNA isolated from whole lung samples. (e) ELISA was used to determine whole lung levels of IFN-γ, IL-4, IL-13, TGF-β, CCL22, and CCL17. Data are mean ± SEM, n = 5–10 mice/group; and compared with the appropriate control group.

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