Human leukocytes regulate ganglioside expression in cultured micro-pig aortic endothelial cells

Abstract

Gangliosides are ubiquitous components of the membranes of mammalian cells that are thought to play important roles in various cell functions such as cell-cell interaction, cell adhesion, cell differentiation, growth control, and signaling. However, the role that gangliosides play in the immune rejection response after xenotransplantation is not yet clearly understood. In this study, the regulatory effects of human leukocytes on ganglioside expression in primary cultured micro-pig aortic endothelial cells (PAECs) were investigated. To determine the impact of human leukocytes on the expression of gangliosides in PAECs, we performed high-performance thin layer chromatography (HPTLC) in PAECs incubated with FBS, FBS containing human leukocytes, human serum containing human leukocytes, and FBS containing TNF-α. Both HPTLC and immunohistochemistry analyses revealed that PAECs incubated with FBS predominantly express the gangliosides GM3, GM1, and GD3. However, the expression of GM1 significantly decreased in PAECs incubated for 5 h with TNF-α (10 ng/mL), 10% human serum containing human leukocytes, and 10% FBS containing human leukocytes. Taken together, these results suggest that human leukocytes induced changes in the expression profile of ganglioside GM1 similar to those seen upon treatment of PAECs with TNF-α. This finding may be relevant for designing future therapeutic strategies intended to prolong xenograft survival.

GM1 Induced the inflammatory response related to the Raf-1/MEK1/2/ERK1/2 pathway in co-culture of pig mesenchymal stem cells with RAW264.7

“…Additionally, xenotransplanted cells, including vascularized organ xenografts, show loss of function within a short time of transplantation in dissonant species combinations. Previous studies reported that gangliosides are related to the inflammatory responses induced in co-culture of xenogeneic cells, such as pig endothelial cells (PAECs) and human leukocytes (Cho et al 2012 ). The inflammatory responses were associated with the mitogen-activated protein kinase (MAPK) family (Yin et al 2016 ).…”

The current state of xenotransplantation

“…Transplantation of wild type pig organs into non-human primates activates the complement cascade by binding naturally occurring preformed antibodies to carbohydrate Galα(1,3)Gal epitopes on the surface of porcine endothelial cells (ECs) causing hyperacute rejection (HAR) (Lexer et al 1986 ). Type I (nontranscriptional) activation is rapid and leads to ECs retraction, expression of P-selectin (CD62P), secretion of the platelet activating factor (PAF) and loss of the antithrombotic phenotype (Cho et al 2012 ). Immunoglobulin G (IgG) after specific binding to target carbohydrate antigens on endothelial cell membranes induces C3b production and complement-mediated vascular collapse.…”

Xenotransplantation literature update, January–February 2013

“…Gangliosides in the membranes of mammalian cells are involved in various cell functions, including cell-cell interaction, cell differentiation, growth control, and signaling. Cho et al [10] studied the role of gangliosides in xenogeneic rejection by analyzing the impact of human leukocytes on the expression of gangliosides in PAEC. High-performance thin layer chromatography and immunohistochemistry analyses showed that PAEC incubated with medium containing fetal bovine serum predominantly expressed the gangliosides GM3, GM1, and GD3.…”

“…Cho et al. studied the role of gangliosides in xenogeneic rejection by analyzing the impact of human leukocytes on the expression of gangliosides in PAEC. High‐performance thin layer chromatography and immunohistochemistry analyses showed that PAEC incubated with medium containing fetal bovine serum predominantly expressed the gangliosides GM3, GM1, and GD3.…”