Relationship between ganglioside GD1a and inflammatory response in the coculture of human endothelial cells with porcine endothelial cells

Abstract

Gangliosides are ubiquitous components of cell membranes that can act as mediators of cell adhesion and signal transduction. However, their interaction with adhesion molecules in vascular grafts following xenotransplantation is not yet clearly understood. In this study, human umbilical vein endothelial cells (HUVECs) were cocultured with porcine aortic endothelial cells (PAECs) in order to investigate the expression patterns of gangliosides, inflammation factors, and the mRNA levels of adhesion molecules by PCR and western blot. The expression of gangliosides GM3 and GM1 was detected in both HUVECs and PAECs, while GD3 was expressed only in PAECs. However, when HUVECs were cocultured with PAECs, GD1a expression was newly detected. In addition, we observed the mRNA expression levels of adhesion molecules including such as E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and platelet endothelial cell adhesion molecule-1 were higher in cocultured HUVECs with PAECs than in either HUVECs or PAECs cultured alone. Furthermore, when HUVECs were cocultured with PAECs, cell growth was significantly inhibited compared with either HUVECs or PAECs. The growth inhibition of both cocultured cells and HUVECs by lipopolysaccharide was significantly increased by GD1a treatment. When HUVECs with PAECs were cocultured, expression of GD1a and inflammatory factors including tumor necrosis factor-α (TNF-α), p65, and p50 significantly increased. These results suggest that GD1a interact with components of the proinflammatory response pathway in xenotransplantation. Therefore, may be relevant for designing future therapeutic strategies intended to prolong xenograft survival.