Abstract
Purpose :
Adipose-derived stem cells (ASCs) have been gaining big interest in retinal vascular and neuronal regeneration thanks to their convenient isolation and easy clinical application. We have shown that CD140b is constitutively expressed in ASCs, controlling their proliferation, adhesion and migration. The aim of the current study is to investigate the specific role of ASCs-CD140b in regulating their angiogenic potential to human retinal endothelial cells (HREs) through both direct and paracrine pathways.
Methods :
Human ASCs with and without CD140b were obtained with transient transfection protocol. Direct effect of CD140b+ or CD140b- ASCs (n=5 donors) on HREs was examined by co-culturing both in 12:1 ratio for 6 days. Endothelial network formation was assessed by Isolectin B4 staining followed by Image J analysis. Concentrated conditioned media (CM, n=2 donors) of CD140b+ or CD140b- ASCs were used to assess HREs migration through scratch wound assay; and vascular permeability by means of trans-endothelial resistance (TER) in presence of TNF-α (1ng/mL)+ High glucose (HG, 30 mM)
Results :
Our transfection protocol resulted in 80% decrease in gene and protein expression of CD140b in ASCs. Co-culturing HREs with CD140+ ASCs resulted in robust angiogenic tube formation with a mean tube length of 7460 pixels/cm2. Co-culturing HREs with CD140b- ASCs significantly decreased mean tube length to (1528.4 pixels/cm2, p<0.05). CM of either CD140b+ or CD140b- ASCs demonstrated comparable effect on HREs migration as evidenced by close significant increase in % reduction of scratch width (Control, 8.3±3.1; CD140b+, 27.6±0.17; Cd140b-, 26.3±2.6, p<0.05). HREs exposed to TNF-α/HG experienced sustained reduction in barrier integrity as evidenced by decreased TER (Control, 1.0±0.0; TNF-α/HG, 0.63±0.07; p<0.01). These effects were equally rescued by treatment with CM of either CD140b+ or CD140- ASCs (CD140b+ASCs, 0.78±0.13; CD140b-ASCs, 0.9±0.0; p>0.05).
Conclusions :
Our data demonstrate a direct cell-mediated but not paracrine mechanism for CD140b in the exerted angiogenic effect of ASCs to HREs. Future studies are needed to fully explore the receptors and underlying signaling mechanism of CD140b in angiogenic potential of ASCs.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.