Double immunofluorescence showing expression of smooth muscle α-actin (α-SMC) and SMemb in thin sections of uninjured coronaries, post PTCA-coronary arteries, uninjured SEV and SEV-grafts in swine.

<p>Expression of α-SMC (green) and SMemb (red) are noted in uninjured coronary artery at low (20x) (A) and high (40x) magnification (B, C, D). Less expression of α-SMC (green) and increased expression of SMemb (red) are found in the hyperplastic region post PTCA- coronary arteries (arrows) at low (20x) (E) and high (40x) magnification (F, G, H). Similarly, immunopositivity to α-SMC (green) and SMemb (red) are observed in the uninjured SEV at low (20x) (I) and high (40x) magnification (J, K, L) compared to SEV post CABG, where few cells are immunopositive to α-SMC (green) and many cells showed immunopositivity to SMemb (red) at low (20x) (M) and high (40x) (N, O, P) magnification. Increased density of SMemb-immunopositive cells are found at the neointima in post PTCA- coronary arteries and SEV-grafts compared to that of normal uninjured coronary artery and vein, respectively. Strong expression of α-SMA is noted in all the vessels, injured or uninjured. This is a representative of tissue histology in 2–5 individual swine in each experimental group. L: lumen, M: medial layer, NI: neointima.