Limitation of donor source for allograft makes the research on xenograft progress. Pig is regarded as one of the ideal donor animals. The major obstacle in xenograft is hyperacute rejection, which is caused by complements after they are activated by xenogeneic antigens combined with natural antibodies. It has been confirmed that alpha-Gal is the major target antigen, whose expression is incharged by alpha-1,3 galactosyltransferase (alpha-GT). The approaches to overcome hyperacute rejection against alpha-Gal included: immunoadsorption of xenogeneic natural antibodies, lysis of antigen by enzyme and genetic manupilation to obtain animal lack of alpha-GT. Besides alpha-Gal, there were other antigens binding to human serum antibody, such as gp65 and gp100, which was expressed on PAEC after induced by TNF, the A-like antigen. But their function was still unknown. It was debatable on the role of MHC in xenograft. Both direct and indirect pathway were involved in cellular response in xenograft.
ObjectiveTo compare the effect and safety of basiliximab in ABO incompatible pediatric liver transplant recipients.MethodsABO incompatible pediatric liver transplantation operated between January 2019 and August 2020 were studied. The patients were allocated randomized into two groups. Patients in experimental group were treated with basiliximab as immune induction therapy, but basiliximab was not used in patients of control group. Tacrolimus combined methylprednisolone were used after liver transplantation. The clinical characteristics, graft and recipient survival rate, rejection, infectious complications, and kidney functions after liver transplantation were observed. Donor specific antibody (DSA) was tested in 3 months after liver transplantation. The growth and development were assessed too after liver transplant.ResultsFourty-four patients were enrolled in the study, including 19 patients in the experimental group and 25 patients in the control group. The median follow-up time was 16.6 months (3.8–25.4 months), and there were no statistically differences between the two groups in terms of age, sex, weight, pediatric end-stage liver disease (PELD) score, and other basic conditions. There were no significant differences between the two groups in tacrolimus dose, tacrolimus trough concentration, kidney functions, height and weight growth after liver transplantation. There were no statistical differences in lung infection, blood stream infection within 3 months after liver transplantation, cytomegalovirus, EBV infection, graft/patient survival rate after liver transplantation (P>0.05). However, the acute rejection rate was lower and the DSA positive rate in 3 months after liver transplantation was lower in the experimental group (P<0.05).ConclusionsBasiliximab can be safely used in ABO incompatible pediatric liver transplant recipients. Acute rejection rate and DSA positive rate after transplantation can be decreased with the useof basiliximab.
Objective To study the immunological rejection occurred in different period after the in vivo implantation of vitreous-cryopreservation tissue engineered tendons for the repair of tendon defect and investigate its influences on the hepatic, renal, and cardiovascular function of rats. Methods Tenocytes obtained from tail tendon of one-weekold SD rats were cultured in vitro. The tenocytes at passage 2-4 (5 × 106 cells/mL) were co-cultured with 1.5 cm bio-derived tendon material to reconstruct tissue engineered tendon. The 21% DMSO was used as cryopreservation protection solution andthe Eurocoll ins solution served as basic solution for pre-frozen solution (4 ) and eluent. The cell-scaffold composites were vitreous-cryopreserved by self-designed method. Seventy-two healthy SD rats (male and/or female) weighing 210-230 g were randomly divided into three groups: group A (n=32), group B (n=32), and group C (n=8). The 0.5 cm tendon defect model was establ ished in the middle part of Achilles tendon in groups A and B. The defect in group A and B was repaired by the transplantation of tissue engineered tendon with and without vitreous-cryopreservation, respectively. At 2, 4, 6, and 8 weeks after transplantation, the general observation and the detection of hepatic function, renal function, and cardiovascular function were conducted. At 2, 4, and 6 weeks after transplantation, serum immunology test was conducted. Results There were no tissue necrosis, hydrops, and suppurative infection in groups A and B. The adhesion was evident in groups A and B 2 weeks after transplantation, improved gradually during 4-6 weeks, and disappeared at 8 weeks. The neonatal tissue had full integration and continuity, and the bridging region of the tendon healed and was similar to the normal tendon. For serum IgG and IgM content, there was no significant difference when group A or B was compared with group C, and between group A and group B 2, 4, and 6 weeks after transplantation (P gt; 0.05). Hepatic function: aspartate aminotransferase (AST) content of group A was less than that of group C 4 weeks after transplantation (P lt; 0.05); AST content of group B was less than that of group C 4 and 6 weeks after transplantation (P lt; 0.05); but there was no significant difference when group A or B was compared with group C in terms of other indexes 8 weeks after transplantation (P gt; 0.05). Renal function: serum albumin and creatinine in groups A and B were decreased obviously, and significant difference was evident when compared with group C (P lt; 0.05). Cardiovascular function: there was no significant difference between group A and group C in terms of blood glucose, triglyceride, and cholesterol (P gt; 0.05);there was a significant difference between group B and group C in terms of triglyceride 8 weeks after transplantation (P lt; 0.05). Conclusion Repairing tendon defect with the implantation of vitreous-cryopreservation tissue engineered tendons results in no obvious immunological rejection and exerts no obvious influences on hepatic, renal, and cardiovascular function.
Objective To discuss the differentiation between transient intrahepatic cholestasis (TIHC) and acute rejection (AR) after liver transplantation． Methods Characteristics and the changes (before and within 21 d after transplantation) of alanine aminotransferase (ALT) and direct bilirubin (DBIL) in 30 patients undergone liver transplantation were observed. These patients were divided into TIHC group and AR group following the diagnosis criteria, and the serum levels of ALT and DBIL were compared respectively on day 1 before liver transplantation, day 3, 7 and 21 after liver transplantation． Results Compared with day 3 after transplantation in the TIHC group， DBIL significantly ascended while ALT was changeless on day 7 after transplantation. But in the AR group， DBIL ascended significantly and ALT showed an increasing tendency on day 7 after transplantation． After appropriate therapy, DBIL and ALT of two groups both descended significantly on day 21 after transplantation． Conclusion The changes of DBIL and ALT are available for the differentiation between TIHC and AR after transplantation.
Objective To establish the rat orthotopic liver transplantation model by characterizing the blood supply of hepatic artery with the Cuff skill and the modified arterial sleeve anastomosis, to explore the possible mechanisms of acute rejection and the express of Fractalkine (Fkn) in the early stage after hepatic allograft operation. Methods SD rats were selected as donors and Wistar rats as receptor for the rejection model of orthotopic liver transplantation. Recipient rats were divided into 2 groups randomly after operationand the drugs were given intraperitoneally once a day in each group. In the experimental group, cyclosporine A (CsA) was delivered with 3 mg/kg. In the control group, only normal saline was given with 3 ml/kg. Condition of survivals were observed. The rejection actvity index (RAI) and the expression of Fkn of liver tissue were observed after 3rd, 5th and 7th days in 5 rats. The rest of rats in each group were fed and given drug or normal saline until they were died and the mean survival time were recorded. Results There were 18 survivals in control group, and 19 in experimental group after liver transplantation. Condition of survivals in experimental group was better than that of control group. The mean survival times of experimental group(19.50±4.51 days) was significantly longer than that of control group(7.60±1.60 days), showing statistically significant difference (P＜0.05). After 3rd, 5th and 7th days of transplantation, RAI of control group were 3.80±0.35,5.90±0.87 and 7.50±1.30,respectively;RAI of experimental group were 3.10±0.21,3.90±0.41 and 4.50±0.52.Therewasstatistically significant difference in RAI between 2 groups on the 7th day after transplantation (Plt;0.01). On the 3rd,5th and 7th days after transplantation, the Fkn of control group was 8.20±0.57,21.30±3.30 and 25.70±4.91, and that of experimental group was 8.30±0.56,10.30±0.67 and 11.70±1.23. There were statistically significant differences in Fkn between 2 groups on the 5th, 7th days after transplantation (Plt;0.01). Conclusion Fkn is a participant inacute rejection after the rat orthotopic liver transplantation and can be chosen as a useful target in the diagnosis of acute rejection. CsA has immunosuppressive property in the condition of acute rejection in the rat orthotopic liver transplantation, which may be result from the decreased the level of Fkn.
Objective
To investigate the effect of human placental-derived mesenchymal stem cells (PMSCs) on immunological rejection in mouse allogeneic skin transplantation.
Methods
The placenta fetal tissues from voluntary donors were used to isolate and culture the PMSCs, and the 3rd passage PMSCs were used in the experiment. Thirty Vr
∶
CD1 (ICR) mice at age of 1-2 days were used as skin donors for allogeneic skin transplantation. Thirty C57BL/6 mice at age of 6-8 weeks as recipients were made back skin defect of 12 mm in diameter and were randomly divided into 3 groups (n=10): group A, autograft; group B, allogeneic graft + PBS tail vein injection; and group C, allogeneic graft + human PMSCs (1 × 105 cells/mouse) tail vein injection. The flap survival was observed. At 7 days after skin transplantation, blood leukocyte counting, abdominal fluid macrophage activation, and the expression levels of interleukin 4 (IL-4), interleukin 17 (IL-17), and interferon γ (INF-γ) in blood and spleen were detected by ELISA and RT-PCR, respectively.
Results
The flap survival time was significantly longer in group A [(58.33 ± 4.04) days] than in groups B and C [(3.80 ± 0.92) days and (6.80 ± 0.82) days] (P lt; 0.05), and in group C than in group B (P lt; 0.05). At 7 days after transplantation, the blood leukocyte number was (6.32 ± 0.45) × 109/L in group A, (7.45 ± 0.52) × 109/L in group B, and (6.35 ± 0.39)× 109/ L in group C, and it was significantly more in group B than in groups A and C (P lt; 0.05). The macrophage activation rate of the abdominal fluid was 6.87% ± 2.40% in group A, 7.84% ± 0.44% in group B, and 15.98% ± 2.87% in group C; group C was significantly higher than groups A and B (P lt; 0.01). ELISA results showed that there was no significant difference in the concentrations of IL-4 among 3 groups (P gt; 0.05). Compared with group B, the concentrations of IL-17 and IFN-γ were significantly reduced in group C (P lt; 0.05), while the concentration of IFN-γ was significantly increased in group B when compared with group A (P lt; 0.05). RT-PCR results showed that there were significant differences in the expressions of IL-4, IL-17, and IFN-γ mRNA between groups B, C and group A (P lt; 0.05); the expressions of IL-4 and IFN-γ mRNA were significantly lower in group C than in group B (P lt; 0.05).
Conclusion
Human PMSCs transplantation can suppress the acute immunological rejection in allogeneic skin transplantation. The possible mechanism may be partially related to the inhibitory effect on the secretion of IL-17 and IFN-γ.
Abstract: Objective To assess the feasibility of transferring major histocompatibility complex (MHC) gene into the thymus to mitigate xenograft rejection. Methods By molecular cloning technique, we extracted and proliferated the-H-2K d gene from donor mice (MHC class Ⅰ gene of Balb/c mice) and constructed the expression vector plasmid of pCI-H-2K d. Twenty SD rats were selected as receptors, and by using random number table, they were divided into the experimental group and the control group with equal number of rats in each group. By ultrasoundguided puncture and lipofection method, the pCI-H-2Kd was injected into thymus of SD rats in the experimental group and meanwhile, empty vector plasmid of pCIneo was injected into thymus of SD rats in the control group. Subsequently, we transplanted the donor mice myocardium xenografts into the receptor rats, and observed the xenograft rejection in both the two groups. Results The survival time of the xenotransplanted myocardium in the experimental group was significantly longer than that in the control group (14.61±2.98 d vs. 6.40±1.58 d, t=-7.619,Plt;0.05). Microtome section of transplanted myocardium in the control group showed a relatively large amount of lymphocyte infiltration and necrosis occurred to most part of the transplanted myocardium, while microtome section of experiment group showed no lymphocyte infiltration and most of the cells of the transplanted myocardium were still alive. After mixed lymphocyte culture, the reaction of receptors to donor cells in the experiment group was obviously lower than that in the control group (t=4.758, P=0.000).After the count by flow cytometer, the xenoMHC molecules were expressed in the receptors’ thymus with a transfection efficiency of 60.7%. Conclusion Our findings suggest that xenograft rejection can be mitigated substantially by donor’s MHC gene transferring into receptor’s thymus. This may provide theoretical and experimental evidence for inducing xenotransplantation tolerance.
Abstract: Objective To study the antiacute rejection effect of Pachymic acid (PA) in heart transplantation rats, in order to select a new antirejection medicine with low side effect from traditional Chinese medicine. Methods We established the model by transplanting Wistar rats (32,donor) heart allografts into the abdomen of SD rats (32,receptor). The homologous hearttransplanted rats were then randomly divided into 4 groups with 16 rats in each group. Olive oil solution with PA 1 mg/(kg·d), PA 10 mg/(kg·d), Cyclosporine (CsA) 5 mg/(kg·d) and olive oil solution 0.5 ml/(kg·d) were respectively given intragastrically to lowdosage PA group, highdosage PA group, CsA group and the control group till the end of observation. Survival time of heart allografts, heart beating and the histological changes of allografts were examined and serum level of interleukin2 (IL-2) and interferon-γ (IFN-γ) were determined by enzymelinked immunosorbent assay (ELISA). Results Survival time in the highdosage PA group, the lowdosage PA group and the CsA group were 24.90±0.99 d, 15.50±1.60 d and 26.80±0.88 d respectively, which is much better than the control group (6.10±1.10 d, q=22.363, P=0.000; q=44.793, P=0.000; q=49.272,P=0.000). IL-2 serum level in the highdosage PA group, the lowdosage PA group and the CsA group were all lower than that in the control group (q=14.483, P=0.000; q=3.705, P=0.000; =21.418,P=0.000), whileIL-2 serum level in the highdosage group was lower than that in the lowdosage group (q=10.778,P=0.000). Similarly, IFN-γ serum level in the first three groups were all lower than that in the control group (q=16.508,P=0000; q=4.281, P=0.000;q=19.621, P=0.000) and IFNγ serum level in the highdosage group was also lower than that in the lowdosage group (q=14.975, P=0.000). Pathological examination 7 days after the surgery showed that pathologic lesion was much more relieved in the two PA groups and the CsA group than the control group. Conclusion Acute rejection of heart transplantation can be effectively suppressed by PA.
OBJECTIVE:To investigate the index of the rejection of lJle retinal pigment epithelium(RPE)cells transplantation.
METHOD:Allogenic RPE transplantation on rahbits by transcleral technique, the changes of interleukin-2 (IL-2) activity in peripheral blood and the effect of
immunoinhibitor (methylprednisonlone)were detected.
RESLILTS:In the group of simple transplantation,the IL-2 activity in peripheral blood begin to rise in the first day after operation. The peak value occured in the third day,and is still much higher than that of the control group in the 14th day,whereas in the group treated with immunoinhibitor ,there was no obvious difference in the first day after operatlon,in the third day,the IL-2 activity rises slightly,and returned to normal level in the 7th day.
CONCLUSION: After RPE transplantation, the level of IL-2 activity in peripheral blood might serve as an important index to determining and detecting the rejective response.
（Chin J Ocul Fundus Dis,1996,12: 239-241）
Objective To observe the effects of Thymosin α1 （Tα1） on acute rejection after liver transplantation and immune function of T cells. Methods Twenty recipients of liver transplantation due to primary hepatic carcinoma were divided into two groups: Tα1 group (n=10) and control group (n=10). Tα1 group received subcutaneous injection of Tα1 1.6 mg on the first day after liver transplantation and then twice a week for at least one month. Both Tα1 group and control group took same immunodepressants. Core biopsies were carried to compare the incidence rate of acute rejection between Tα1 group and control group. Peripheral T cellular immune function in these two groups was detected on 1 d before, 1 week, 2 weeks and 1 month after transplantation. Results There was not significant difference of incidence rate of acute rejection between Tα1 group and control group (Pgt;0.05). In the Tα1 group, CD4+, CD8+ lymphocyte cell counts and the CD4+/CD8+ ratio were significantly higher than those in the control group in 2 weeks and 1 month after transplantation (P＜0.05). Conclusion Use of Tα1 in recipients who also takes rountine immunosuppressants dose not increase the risk of occurring acute rejection after liver transplantation. Tα1 can significantly increase CD4+, CD8+ counts and CD4+/CD8+ ratio, which shows that Tα1 may improve recipients’ cellular immune function.
