Figure 4.

G-MDSC–associated effect on vascular remodeling in PH. (A) Immunohistochemical (IHC) staining for α-smooth muscle actin (α-SMA; brown, arrowheads) of lung sections from bleomycin-exposed mice, collected at time of time of death. Scale bar: 500 μm, magnification ×20. (B) Complete and partially muscularized vessels were counted from 10 microscopic fields and ratio calculated. (C) Medial wall thickness of pulmonary vessels was assessed by averaging from 10 random high-powered fields, opposing wall thickness of vessel (W1 and W2), in ratio to total diameter (d) (d = ([W1 + W2] / d) × 100%); n = 12 per mouse group over course of three independent experiments. Results are plotted as the mean (±SEM). *P < 0.05. HPF = high power field.