Figure 4:Tubular-like structures formation in HC-MSCs transfected with siRNA-Ang1 (a) HC-MSCs was transfected with specific siRNA-Ang1 or non-targeting siRNA (NT), and Ang1 expression was evaluated by qRT-PCR. The cells transfected with siRNA-Ang1 showed a decreased gene expression of Ang1 when compared with cells transfected with siRNA-NT. (b) Phase contrast pictures: HC-MSCs-siRNA-NT co-cultured with HC-ECs (left panel) and SSc-ECs (right panel). HC-MSCs-siRNANT, when co-cultured with HC-ECs, formed organized tube-like structure, on the contrary when co-cultured with SSc-ECs, the capacity to improve the tubular formation was decreased. (c) Phase contrast pictures: HC-MSCs-siRNA-Ang1 co-cultured with HC-ECs (left panel) and SSc-ECs (right panel): HC-MSCs-siRNA-Ang1 lack the ability to support the tubologenesis of both HC- and SSc-ECs. Pictures are representative of all experiments. Original magnifications 20X. (d) The total tube length of each well was measured as branching index= (master junction/area)*1000 and photographed. Results are expressed as Median (range) of triplicate experiments (*=p=0.008, **=p=0.0002, ***=p=0.0001).