Figure 5.

Adoptive transfer of HO₂-EVs increases lung inflammation. (A) H&E staining showed increased cellular infiltration into the alveolar airspaces in HO₂-EV–injected lung tissue sections. (B) Immunostaining for Mac3 demonstrated increased alveolar macrophages (AMs) in HO₂-EV–injected lungs compared with the other two groups (C). The LO₂-EV–injected lungs also had slightly higher macrophage counts compared with the control EV–injected lungs (C). (D) Zoomed magnification of the red box. (E) Immunostaining for iNOS detected positive stained AMs in HO₂-EV–injected lungs. (F) Zoomed magnification of the red box. (G) Immunostaining for Ym1 detected positive stained AMs in HO₂-EV–injected lungs. (H) Zoomed magnification of the red box. Objective magnification, 20×. Scale bars, 50 μm. n = 5 per group. *P < 0.05 and ****P < 0.0001. HPV = high-power view; iNOS = inducible nitric oxide synthase.