Figure 3. PLK1 inhibition can alleviate rejection in the early and late inflammatory phases. (A–D) BI6727 treatment alleviates airway epithelial loss 7 days after transplantation. (A) Representative H&E and PAS stains of tracheal grafts 7 days post-transplantation. (B) Percentage of luminal occlusion in the BI6727 treatment and control groups. (C, D) Sections were graded by two investigators independently, followed by blind treatment. (E) Representative immunohistochemical stains of tracheal grafts 28 days post-transplantation. (F) Percentage of luminal occlusion in the BI6727 treatment and control groups 28 days after transplantation. (G) Sections were graded by two investigators independently, followed by blind treatment. (H, I) The expression of collagenous fiber (H) and collagen I (I) in the BI6727 treatment and control groups 28 days after transplantation. (J) The percentage of α-SMA positive cells in the BI6727 treatment and control groups. * P≤0.05, H&E; haematoxylin-eosin, PLK; polo-like kinase, SMA; smooth muscle actin.