Xinshun Feng

Clinical Application of Cordyceps sinensis on Immunosuppressive Therapy in Renal Transplantation

OBJECTIVE We sought to explore the adjunctive effects of Cordyceps sinensis (CS) in clinical renal transplantation. MATERIALS AND METHODS Patients (n = 202) were divided randomly by lottery into a treatment (n = 93) and a control group (n = 109). Patients in the treatment group were treated with CS 1.0 g 3 times a day in addition to the immunosuppressive regimen given to the control group. We compared patient and graft survivals, incidence, time and severity of acute rejection episodes, chronic allograft nephropathy (CAN), hepatotoxicity and nephrotoxicity, biochemistry parameters including indicators of liver and kidney functions, fats, proteinuria, dosages, and whole blood concentrations of cyclosporine (CsA). RESULTS Patient and graft survival rates, serum creatinine (SCr), and blood urea nitrogen (BUN) were not significantly different between the 2 groups (P > .05). Serum uric acid (UA) and 24-hour urinary total protein (24-hour UTP) were significantly lower in the treatment group than in the control group (P < .05). The incidences (11.83% vs 15.60%) and times to acute renal allograft rejection (23.48 +/- 7.22 vs 22.27 +/- 8.03 days posttransplantation) were not significantly different between the treated and control groups (P > .05). Patients receiving thymoglobulin antirejection therapy (3 cases) were fewer in the heated versus control group (13 cases; P = .014). The incidences of hepatotoxicity and nephrotoxicity in the treated group were 12.90% and 19.35%, significantly lower than 24.77% and 33.94% in the control group, respectively (P < .05). At 2 to 6 months posttransplantation, the CsA dosages in the treated group were significantly lower than those in the control group (P < .05). The whole blood trough CsA concentrations in the treated group were significantly lower than those in the control group at 3 to 6 months posttransplantation (P < .05). The decreasing trends of the 2 aforementioned parameters in the treatment group were approximately linear among treated subjects compared with approximately quadratic in the control group (P < .05). The incidence of CAN in the treated group was 7.53%, which was significantly lower than 18.35% in the control group (P = .024). The 24-hour UTP level in CAN patients within the treated group was significantly lower than the control group after transplantation (P = .045). The differences in total bilirubin, SCr, serum UA, and total cholesterol levels among otherwise normal patients in the treated group were significantly lower than those among the control group (P < .05). CONCLUSIONS The use of CS may allow decreased dosages and concentrations of CsA causing fewer side effects without an increased risk of acute rejection. In addition, CS with reduced dose CsA may decrease proteinuria and retard CAN progression.

Study on systemic immune tolerance induction in rat islet transplantation by intravenous infusion of Sertoli cells.

Background. Sertoli cells are usually co-transplanted with pancreatic islets to induce local immune tolerance. In this report, we used infusion with Sertoli cells in islet transplantation to induce systemic immune tolerance and studied the mechanism of the tolerance induction. Methods. Streptozotocin-induced diabetic rats were divided into four groups before islet transplantation: group A as control; group B with intravenous infusion of Sertoli cells; group C with Sertoli cell infusion and Fas ligand antibody treatment; and group D with Sertoli cell infusion and transforming growth factor-&bgr;1 antibody treatment. The mean survival time (MST) and insulin expression of islet grafts were measured. The number of lymphocytes and the levels of cytokines in peripheral blood were also measured. Results. Group B had the longest MST of islet allografts (41.6±4.20 days) followed by groups C, D, and A (P<0.05). Immunohistochemistry showed similar results with MST. The rats in group B had the least CD4+ T cells (only 15.6%±6.4%) compared with other groups (P<0.05). The numbers of CD8+ T cells in rats of groups B (11.2%±4.3%) and D (14.5%±5.6%) were significantly lower than those of groups A and C (P<0.05). After transplantation, group Bs interleukin (IL)-2 level (1.92±0.68 ng/mL) was found to be significantly lower than that of other groups (P<0.05). Interferon-&ggr; showed similar pattern of change as IL-2 (P<0.05). Groups A and D had significantly lower levels of IL-4 (4.31±1.97 pg/mL 4.69±1.33 pg/mL, respectively) than groups B and C (P<0.05). Conclusion. Infusion of Sertoli cells could effectively prolong the survival of islet grafts and reduce peripheral blood lymphocyte and cytokine levels. In this process, transforming growth factor-&bgr;1 played a major role and Fas ligand played a smaller additional role.

Prolongation of Islet Graft Survival Using Concomitant Transplantation of Islets and Vascular Endothelial Cells in Diabetic Rats

BACKGROUND The transplantation of isolated islets of Langerhans is nearing acceptance as treatment of type 1 diabetes mellitus. Because the arterial and venous connections of the pancreas are disrupted during islet isolation, islets must be revascularized after transplantation. OBJECTIVE To observe whether increased numbers of vascular endothelial cells in islets can affect the angiogenesis and function of the grafts. MATERIALS AND METHODS Rats with streptozocin-induced diabetes were divided into 3 groups. The rats in group 1 received islet grafts under the capsule of the left kidney; rats in group 2 received combined vascular endothelial cell and islet transplants; and rats in group 3 served as controls. After the transplantation procedure, blood glucose and insulin concentrations were evaluated daily. Hematoxylin-eosin and immunohistochemical staining was used to detect expression of vascular endothelial growth factor antibodies in the diabetic rat kidneys. The mean microvascular density was also calculated. RESULTS At 3 days posttransplantation, blood glucose and insulin concentrations returned to normal in group 2, however, they declined only slightly in group 1, and moderate hyperglycemia was present. There was a significant difference in blood glucose and insulin concentrations between the 2 groups after 3 days (P < .05). The mean (SD) microvascular density in group 2 was markedly higher than that in group 1 (12.58 [1.81] vs 10.38 [0.97] P = .04). CONCLUSION This study suggests that concomitant transplantation of isolated islets with endothelial cells can prolong islet graft survival in diabetic rats.

Islet graft survival and function: concomitant culture and transplantation with vascular endothelial cells in diabetic rats.

Background. Human islet transplantation is a great potential therapy for type I diabetes. To investigate islet graft survival and function, we recently showed the improved effects after co-culture and co-transplantation with vascular endothelial cells (ECs) in diabetic rats. Methods. ECs were isolated, and the viability of isolated islets was assessed in two groups (standard culture group and co-culture group with ECs). Then streptozotocin-induced diabetic rats were divided into four groups before islet transplantation as follows: group A with infusion of islet grafts; group B with combined vascular ECs and islet grafts; groups C and D as controls with single ECs infusion and phosphate-buffered saline injection, respectively. Blood glucose and insulin concentrations were measured daily. Expression of vascular endothelial growth factor was investigated by immunohistochemical staining. The mean microvascular density was also calculated. Results. More than 90% of acridine orange-propidium iodide staining positive islets demonstrated normal morphology while co-cultured with ECs for 7 days. Compared with standard control, insulin release assays showed a significantly higher simulation index in co-culture group except for the first day (P<0.05). After transplantation, there was a significant difference in concentrations of blood glucose and insulin among these groups after 3 days (P<0.05). The mean microvascular density in co-culture group was significantly higher than that in single islet group (P=0.04). Conclusion. Co-culture with ECs in vitro could improve the survival and function of isolated rat islet, and co-transplantation of islets with ECs could effectively prolong the islet graft survival in diabetic rats.

Allograft rejection-related gene expression in the endothelial cells of renal transplantation recipients after cytomegalovirus infection.

ObjectiveTo explore the effects of cytomegalovirus (CMV) infection on rejection-related gene expression in the endothelial cells of renal transplantation recipients.MethodsEndothelial cells (ECs) were cultured and stimulated by a variety of factors: A, normal control group; B, inactivated human cytomegalovirus (HCMV) infection group; C, HCMV infection group; D, HCMV supernatant infection group; and E, ganciclovir HCMV group. Expression of intercellular adhesion molecule-1 (ICAM-1) and major histocompability complex (MHC) class I and class II antigens was detected by flow cytometry (FCM) and immunohistochemistry.ResultsWe found characteristic CMV-infected ECs in this study. There were no significant differences among groups A, B and D (P>0.05). Although the expression levels of ICAM-1 were not significantly different between groups C and E (P>0.05), the ICAM-1 expression in these two groups was significantly higher than that in group A (P<0.05). ICAM-1 expression was detected in groups C and E, while there was no expression in groups A, B and D. Furthermore, there was no significant difference of ICAM-1 mRNA expression between groups C and E (P>0.05). Human leucocyte antigen (HLA)-ABC expression was detected in all the groups, while HLA-DR expression was only detected in groups C and E. There were no significant differences of HLA-ABC and HLA-DR expression among groups A, B and D (P>0.05). However, the HLA-ABC and HLA-DR expression levels in groups C and D were higher than those of the remaining groups previously reported (P<0.05). Meanwhile, the HLA-ABC and HLA-DR expression levels in group E were lower than those of group C (P<0.05).ConclusionCMV could up-regulate the expression levels of ICAM-1 and MHC antigens, which was closely related to allograft rejection.

Improved survival and function of rat cryopreserved islets by coculture with sertoli cells.

In order to investigate how to improve the function and survival of cryopreserved islets, we cocultured cryopreserved thawed rat islets with rat Sertoli cells. After thawing, the islets were divided into the Sertoli cell coculture group and the control group. Using light and transmission electron microscopes, we examined the morphology of islets and measured their apoptosis index (AI) and insulin release stimulation index (SI). Moreover, we measured apoptosis protein and mRNA by western-blot and reverse transcription polymerase chain reaction and cytokine concentrations in supernatant by ELISA. We examined islet graft survival time in diabetic mice and detected insulin in grafts by immunohistochemistry. We found that the morphology, AI, and SI of the coculture group were all significantly improved. The relative expression levels of cleaved caspase-3 P20, P11, and caspase-7 in the coculture group were lower than those in the control group. Compared with the control group, the expression level of Bax was decreased, but that of Bcl-2 was increased. After transplantation, islet survival in the coculture group was similar to that of fresh islets but longer than that in the control group. These results suggest that coculture with rat Sertoli cells significantly improves the yield and function of rat cryopreserved thawed islets by effectively reducing islet apoptosis.

Combined Strategy of Endothelial Cells Coating, Sertoli Cells Coculture and Infusion Improves Vascularization and Rejection Protection of Islet Graft

Improving islet graft revascularization and inhibiting rejection become crucial tasks for prolonging islet graft survival. Endothelial cells (ECs) are the basis of islet vascularization and Sertoli cells (SCs) have the talent to provide nutritional support and exert immunosuppressive effects. We construct a combined strategy of ECs coating in the presence of nutritious and immune factors supplied by SCs in a co-culture system to investigate the effect of vascularization and rejection inhibition for islet graft. In vivo, the combined strategy improved the survival and vascularization as well as inhibited lymphocytes and inflammatory cytokines. In vitro, we found the combinatorial strategy improved the function of islets and the effect of ECs-coating on islets. Combined strategy treated islets revealed higher levels of anti-apoptotic signal molecules (Bcl-2 and HSP-32), survival and function related molecules (PDX-1, Ki-67, ERK1/2 and Akt ) and demonstrated increased vascular endothelial growth factor receptor 2 (KDR) and angiogenesis signal molecules (FAk and PLC-γ). SCs effectively inhibited the activation of lymphocyte stimulated by islets and ECs. Predominantly immunosuppressive cytokines could be detected in culture supernatants of the SCs coculture group. These results suggest that ECs-coating and Sertoli cells co-culture or infusion synergistically enhance islet survival and function after transplantation.

Improved Islet Survival and Funtion With Rat Endothelial Cells In Vitro Co-Culture

OBJECTIVE Pancreatic islet transplantation is an emerging therapy for type 1 diabetes. To preserve its function, transplanted islets must be revascularized because arterial and venous connections are disrupted during islet isolation. The current paradigm is that islet revascularization originates from the transplant recipient. This study was designed to test whether the function of isolated islets can be retained by co-culture with thoracic aorta endothelial cells in vitro. METHODS Sprague-Dawley rats were used in this study. The endothelial cells (ECs) were isolated from the thoracic aorta. The viability of the isolated islets was assessed by acridine orange/propidium iodide (AO/PI) double staining. The islets were either placed in standard cultures (group A) or in co-cultures with ECs (group B). Islet viablity was assessed by an insulin release assay. RESULTS The islets in group B exhibited normal morphology with >90% staining positive as detected by AO/PI with 7 days. Insulin release assays showed a significantly higher simulation index (SI) in group B compared with group A (P < .05) except on the first day. CONCLUSION This study suggested that co-cultrue of freshly isolated rat islets with ECs improves postculture survival and islet function in vitro.

Long-term follow-up of co-administration of diltiazem and cyclosporine in Chinese kidney transplant recipients.

Background: Co-administration of diltiazem and cyclosporine A (CsA) in kidney transplant recipients shows improvement of renal transplantation outcomes. Methods: We respectively analyzed 1531 kidney transplant recipients treated by different immunosuppressive therapy schemes from 1986 to 2003. They were divided into three groups depending on their immunosuppressive therapy schemes: control group with a standard triple therapy without use of diltiazem; study group I with the combination of diltiazem and the standard triple therapy but slightly low CsA; study group II with combination of diltiazem and a modified standard triple therapy but lower CsA. The CsA blood concentrations, posttransplant complications, and long-term survival in the three groups were compared. Results: The results showed that the patient and allograft survival in the study group II was 69.9 and 65.1%, respectively, significantly higher than that in the control group (50.7 and 47.6%). Occurrence of hepatotoxicity and nephrotoxicity episodes was higher in the control group than those in the study group I and the study group II. The incidence of acute rejection in the control group was 30.3% (23/76), similar to 28.0% (184/657) in study group I, but statistically significantly higher than 7.6% (61/798) in the study group II. Conclusion: Combination of diltiazem and CsA in the kidney allograft recipients tends to reduce the CsA oral dosage, improve patient survival, and decrease the occurrence of hepatotoxicity and nephrotoxicity.

Treatment of Cytomegalovirus infection after renal transplantation: Experience from a Single Center in China

BACKGROUND We compared the efficacy and safety of 2 different treatments of CMV infection, including asymptomatic CMV replication and CMV disease. MATERIAL AND METHODS 852 renal transplantation recipients, including asymptomatic CMV replication and CMV disease, received antiviral therapies of intravenous acyclovir or comprehensive anti-infection solution, mainly with intravenous ganciclovir. Effect, time, acute allograft rejection, and safety were analyzed during the antiviral therapy RESULTS The total effective rates were higher with ganciclovir in both asymptomatic CMV replication (98.96% vs. 84.90%) and CMV disease (96.29% vs. 50.36%). Ganciclovir significantly shortened antiviral therapy duration in both asymptomatic CMV replication (15.0 ± 2.3 days vs. 16.0 ± 3.4 days) and CMV disease (19.7 ± 3.1 days vs. 21.5 ± 4.0 days). The acute allograft rejection incidences were significantly lower with ganciclovir in both asymptomatic CMV replication (8% vs. 14%) and CMV disease (11% vs. 22%). CMV-IEA was detected in renal grafts of patients with acute rejection. There was more CMV-associated acute rejection using acyclovir than using ganciclovir. Except for the higher incidence of anemia leucopenia and anemia with ganciclovir, the safety profiles of both drugs were similar. CONCLUSIONS Comprehensive anti-infection solution, mainly with intravenous ganciclovir, can effectively treat CMV infection, shorten duration of therapy, and decrease acute rejection. The few adverse effects had negligible effects on use of ganciclovir.