Human Placental Mesenchymal Stem Cells for the Treatment of ARDS in Rat

Figure 4

Masson’s trichrome staining, immunohistochemistry, and the fluorescence microscopy of the lung section after ARDS modeling and treatment. (a, b) LPS and LPS+dexamethasone groups. The intense blue staining of collagen fibers surrounding the bronchi and alveolar vessels. (c) Blue staining of collagen fibers in the lung interstitium. Masson’s trichrome staining ×800. (d) LPS+HPMSC group. Slight blue coloration of collagen fibers around the vessels. Masson’s trichrome staining ×200/800. Observation period one week. (e–h) LPS+HPMSC group. HPMSCSs labeled with the PKH26 fluorescent dye on the sections of lung tissue. (e) At 24 hours after their intratracheal injection; H&E staining ×800. (f) Fluorescence microscopy; observation period 24 hours. Magnification ×800; (g, h) Fluorescence microscopy. Observation period 96 hours. Magnification ×800; (i, j) LPS group. α-SMA-positive cells appeared in the area of fibrotic lesions. Magnification ×400/800 (dark brown staining); (k) LPS+dexamethasone group. Intensive staining of α-SMA-positive cells. Magnification ×400; (l) LPS+HPMSC group. Weak α-SMA immunostaining signal. Magnification ×400. Observation period one week.

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