Table 3. Effect of anti-VLA-4 and anti-VEGF treatment on ductus neointima and vasa vasorum remodeling (see Methods for definitions).

A) Luminal endothelial thickness: number of ductus in each group that have either a single or multiple (2, 3 or more) layers of endothelial cells that completely surround the ductus lumen (Chi-Square analysis). B) Neointimal (endothelial, subendothelial and total) thickness: Total thickness is the distance between the lumen and the internal elastic lamina. C) Subendothelial zone thickness > 20 µm: this represents the percentage of the luminal circumference that is surrounded by a thickened (> 20 µm) subendothelial zone. D) Vasa vasorum ingrowth: the distance that vasa vasorum migrate from the adventitia into the muscle media is expressed as the percentage of muscle media thickness.

	Fetus	Newborn Control	Newborn Anti-VLA-4	Newborn Anti-VEGF
	(N=7)	(N=14)	(N=7)	(N=6)
A) Luminal endothelial thickness		*	*	* †
1 layer – n (%)	7 (100)	0 (0)	0 (0)	1 (17)
2 layers – n (%)	0 (0)	2 (14)	2 (30)	4 (67)
≥ 3 layers – n (%)	0 (0)	12 (86)	5 (70)	1 (17)
B) Neointimal thickness
Endothelial zone - µm	8±1	62±38 *	53±25 *	24±10 * †
Subendothelial zone - µm	20±14	66±29 *	27±12 †	19±10 †
Total thickness - µm	29±14	128±47 *	81±30 †	44±10 * †
C) Subendothelial zone > 20 µm
% circumference of lumen	18±7	60±23 *	20±10 †	15±7 †
D) Vasa vasorum ingrowth
% muscle media thickness	8±4	14±6 *	14±6 *	5±3 †

^*p < 0.05 vs fetal ductus;

^†p < 0.05 vs newborn control ductus.

N, number of ductus examined.