Figures
- FIGURE 1
a) Illustration of the normal pulmonary artery and vein structure stained with Movat Pentachrome (4× magnification). The pulmonary arteries are well rounded in structure, while veins are elongated and irregular. b) Movat Pentachrome-stained normal control and idiopathic pulmonary fibrosis (IPF) of pulmonary arteries’ external and luminal length measurement (20× magnification). External length is measured from one end to the other end of the adventitia layer margin crossing the middle of the lumen, while the luminal length was measured from one end to another end of the intima layer margin. In the inset are layers of various thickness (T1 – intima, T2 – media and T3 – adventitia).
- FIGURE 2
Representative images of Movat Pentachrome-stained pulmonary artery sizes for normal control and idiopathic pulmonary fibrosis (IPF): a, b) 100–199 μm, c, d) 200–399 μm, and e, f) 400–599 μm (20× magnification), and g, h) 600–1000 μm (10× magnification). The prominent intimal thickening and luminal narrowing in IPF patients across various sizes are noted. Also noted is the arterial adventitia area merging into the surrounding lung tissues in IPF patients. #: plexiform in part f.
- FIGURE 3
a) Quantitative assessment of the total number of arteries in idiopathic pulmonary fibrosis (IPF) and normal control (NC) across classified arterial sizes and b) arterial length to luminal length log ratio of pulmonary arteries across the classified arterial sizes of IPF compared to NC. Data are presented as log ratio with unpaired t-test between each arterial classified size for NC and IPF. **p<0.01, ***p<0.001, ****p<0.0001 was considered significant.
- FIGURE 4
Correlations between a) total arterial numbers/mean per cent tissue density and % diffusing capacity of the lungs for carbon monoxide (DLCO); b) total arterial length to luminal length log ratio and % DLCO; and c) total arterial length to luminal length ratio for arteries from fibrosed and non-fibrosed area in idiopathic pulmonary fibrosis.
- FIGURE 5
a, b) Arterial layer thickness measurement strategy in normal control (NC) and idiopathic pulmonary fibrosis (IPF). Total arterial thickness was measured by selecting total arterial circumference. Insets show layers of various thickness (T1 – intima, T2 – media and T3 – adventitia) thickness. Morphometric changes in arterial layers among c) total arterial thickness across arterial size 100–1000 µm, d) 100–199 µm, e) 200–399 µm, f) 400–599 µm and g) 600–1000 µm. All data are presented as multiple comparisons with ordinary one-way ANOVA. *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001 was considered significant. ns: nonsignificant.
- FIGURE 6
a, b) Arterial layer elastin measurement strategy in normal control (NC) and idiopathic pulmonary fibrosis (IPF). The black colour represents the elastin count. Insets show various layers (E1 – intima, E2 – media and E3 – adventitia) of elastin. Morphometric changes in arterial layer elastin among c) total arterial elastin across arterial size 100–1000 µm, d) 100–199 µm, e) 200–399 µm, f) 400–599 µm and g) 600–1000 µm. Arterial elastin is expressed as a percentage. All data are presented as multiple comparisons with ordinary one-way ANOVA. *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001 was considered significant. ns: nonsignificant.
- FIGURE 7
Correlations matrix showing the impact on various measured indices on pulmonary function and smoking pack-years: a) pulmonary arterial total thickness, b) arterial individual layer thickness, c) pulmonary arterial total elastin, d) individual arterial layer elastin, and e) correlation between arterial thickness and arterial elastin across each arterial layer. Increased per cent elastin in each layer significantly correlated to their corresponding layer thickness. FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; DLCO: diffusing capacity of the lungs for carbon monoxide.
- FIGURE 8
Descriptive images of immunohistochemically stained pulmonary arteries for VE-cadherin (magnification 20×): a) normal control (NC), b) idiopathic pulmonary fibrosis (IPF), in insets junctional and cytoplasmic expression of VE-cadherin in NC and IPF, respectively (100×). Staining images for: N-cadherin c) NC and d) IPF (20×); S100A4 e) NC and f) IPF; vimentin g) NC and h) IPF; α-SMA i) NC and j) IPF; collagen-I k) NC and l) IPF; and collagen-IV m) NC and n) IPF (all images taken in 20× magnification for medium-size arteries). The black arrows indicate mesenchymal protein expression in the intima, and the red arrows indicate α-SMA+ myofibroblast (in inset intima) and ECM protein: collagen I and collagen IV deposition (in inset intima).
Tables
- TABLE 1
Subject demographics and clinical characteristics
Normal control IPF Total number n 11 13 Age years 41±15.1 64±5.06 Sex (F/M) n 6/5 6/7 Body mass index kg·m−2 NA 26.69±3.03 Smoking status: current/ex-smoker/never-smoker n Nonsmokers 0/7/6 Smoking pack-years 20.84±23.16 Lung physiology FEV1 L 1.70±0.40 FEV1 % predicted 60.17±12.22 FVC L 1.97±0.51 FVC % predicted 53.5±12.98 DLCO mL·min−1·mmHg−1 5.91±2.92 DLCO corrected % predicted 25.85±15.30 Values given as mean±sd unless otherwise stated. IPF: idiopathic pulmonary fibrosis; F: female; M: male; NA: not available; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; DLCO: diffusing capacity of the lungs for carbon monoxide.
