Background Blocking the 4-1BB/4-1BB ligand （4-1BBL） signal may modulate the secretion of Th1/Th2 cytokines and prolong the survival of the grafts, which play a key role in organ transplantation tolerance. The aim of...Background Blocking the 4-1BB/4-1BB ligand （4-1BBL） signal may modulate the secretion of Th1/Th2 cytokines and prolong the survival of the grafts, which play a key role in organ transplantation tolerance. The aim of this study was to investigate the role of blockade of the 4-1BB/4-1BBL co-stimulatory pathway with 4-1BBL monoclonal antibody （mAB） in acute rejection of rat orthotopic liver transplantation. Methods The orthotopic liver transplantation model was set up, while male Lewis rats were used as liver donors and Brown-Norway rats as recipients. The recipient rats were intravenously injected with anti 4-1BBL mAB or isotype control antibody. Groups were monitored for graft survival after transplantation. Plasma chemistry, including aspartate transaminase （AST）, alanine aminotransferase （ALT）, and bilirubin （BIL）, was assayed. The concentrations of interleukin （IL）-2, IL-10 and interferon （IFN）-γ in plasma were also measured by enzyme-linked immunosorbent assay. Allograft histology images were collected under light microscope and electron microscope. Results Isotype antibody treated recipients exhibited elevated plasma levels of liver injury markers including AST, ALT and BIL, progressive portal and venous inflammation and cellular infiltration of the liver ailografts, and a mean graft survival time （MST） of 10.9 days. Administration of anti 4-1BBL mAB resulted in a decrease in plasma levels of liver injury markers and the concentrations of IL-2, IL-10 and IFN-γ. The histological grade of rejection on day 7 decreased and MST （17.3 days） increased substantially. Conclusions These results demonstrate that attenuation of acute rejection follows the blockade of the 4-1BB/4-1BBL co-stimulatory pathway with 4-1BBL monoclonal antibody and strongly suggest it is a promising strategy to prevent progression of graft rejection by suppressing T cell-mediated immunity.展开更多
The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we...The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we examined whether peripheral blood mononuclear cells (PBMCs) from polytransgenic mice expressing the human HT, and complement regulatory proteins (DAF and CD59), can provide more effective protection against xenograft rejection. Transgenic mice were produced by co-injection of gene constructs for human HT, DAF and/or CD59. Flow Cytometry (FCM) was used to screen the positive transgenic mice. PBMCs from transgenic mice were incubated with 15% human serum to evaluate natural antibody binding, complement activation and expression of adhesion molecules. Three transgenes were strongly expressed in PBMCs of transgenic mice, and HT expression signifi- cantly reduced expression of the major xenoepitope galactose-α-1,3-galactose (α-Gal). Functional studies with PBMCs showed that co-expression of HT and DAF or CD59 markedly increased their re- sistance to human serum-mediated cytolysis when compared with single transgenic PBMCs. Moreover, the combined expression of triple transgenes in PBMCs led to the greatest protection against human serum-mediated cytolysis, avoided hyperacute rejection and reduced expression of adhesion mole- cules. Strong co-expression of triple transgenes was completely protected from xenograft hyperacute rejection and partially inhibited acute vascular rejection. The studies suggest that engineering mice to express triple molecules represents an critical step toward prolonging xenograft survival and might be more suitable for xenotransplantation.展开更多
文摘Background Blocking the 4-1BB/4-1BB ligand （4-1BBL） signal may modulate the secretion of Th1/Th2 cytokines and prolong the survival of the grafts, which play a key role in organ transplantation tolerance. The aim of this study was to investigate the role of blockade of the 4-1BB/4-1BBL co-stimulatory pathway with 4-1BBL monoclonal antibody （mAB） in acute rejection of rat orthotopic liver transplantation. Methods The orthotopic liver transplantation model was set up, while male Lewis rats were used as liver donors and Brown-Norway rats as recipients. The recipient rats were intravenously injected with anti 4-1BBL mAB or isotype control antibody. Groups were monitored for graft survival after transplantation. Plasma chemistry, including aspartate transaminase （AST）, alanine aminotransferase （ALT）, and bilirubin （BIL）, was assayed. The concentrations of interleukin （IL）-2, IL-10 and interferon （IFN）-γ in plasma were also measured by enzyme-linked immunosorbent assay. Allograft histology images were collected under light microscope and electron microscope. Results Isotype antibody treated recipients exhibited elevated plasma levels of liver injury markers including AST, ALT and BIL, progressive portal and venous inflammation and cellular infiltration of the liver ailografts, and a mean graft survival time （MST） of 10.9 days. Administration of anti 4-1BBL mAB resulted in a decrease in plasma levels of liver injury markers and the concentrations of IL-2, IL-10 and IFN-γ. The histological grade of rejection on day 7 decreased and MST （17.3 days） increased substantially. Conclusions These results demonstrate that attenuation of acute rejection follows the blockade of the 4-1BB/4-1BBL co-stimulatory pathway with 4-1BBL monoclonal antibody and strongly suggest it is a promising strategy to prevent progression of graft rejection by suppressing T cell-mediated immunity.
基金Supported by the Doctor Initiation Foundation of Zhengzhou University
文摘The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we examined whether peripheral blood mononuclear cells (PBMCs) from polytransgenic mice expressing the human HT, and complement regulatory proteins (DAF and CD59), can provide more effective protection against xenograft rejection. Transgenic mice were produced by co-injection of gene constructs for human HT, DAF and/or CD59. Flow Cytometry (FCM) was used to screen the positive transgenic mice. PBMCs from transgenic mice were incubated with 15% human serum to evaluate natural antibody binding, complement activation and expression of adhesion molecules. Three transgenes were strongly expressed in PBMCs of transgenic mice, and HT expression signifi- cantly reduced expression of the major xenoepitope galactose-α-1,3-galactose (α-Gal). Functional studies with PBMCs showed that co-expression of HT and DAF or CD59 markedly increased their re- sistance to human serum-mediated cytolysis when compared with single transgenic PBMCs. Moreover, the combined expression of triple transgenes in PBMCs led to the greatest protection against human serum-mediated cytolysis, avoided hyperacute rejection and reduced expression of adhesion mole- cules. Strong co-expression of triple transgenes was completely protected from xenograft hyperacute rejection and partially inhibited acute vascular rejection. The studies suggest that engineering mice to express triple molecules represents an critical step toward prolonging xenograft survival and might be more suitable for xenotransplantation.
