Objective To summarize the research progress of programmed cell death protein 1 (PD-1)/programmed cell death protein-ligand 1 (PD-L1) inhibitors before liver transplantation of liver cancer. Method The literatures on the application of PD-1/PD-L1 inhibitors before liver transplantation of liver cancer were collected and reviewed. Results PD-1/PD-L1 inhibitors preoperatively treated liver transplantation recipients had a low incidence of postoperative rejection, and routine usage of hormone and immune tolerance induction therapy in liver transplantation recipients might reduce the incidence of rejection caused by PD-1/PD-L1 inhibitors. Conclusion Preoperative usage of PD-1/PD-L1 inhibitors have more benefits than risks for patients with advanced liver cancer.
【Abstract】Objective This study was conducted to build experimental model of orthotopic liver transplantation in rat (ROLT) with the character of acute rejection; and to study the effect of cytotoxic T lymphocyte antigen 4 immunoglobulin G (CTLA4Ig) on prevention of rejection and the induction of immune tolerance of ROLT. Methods Build model of Wistar→SD ROLT(performed by the two cuff method) with character of acute rejection.Recipients were injected with CTLA4Ig 75 μg per ROLT into abdominal cavity after 2 days of operation. Contrast was made with no treatment group, the clinical characters, the liver function, the transplantated liver pathologic character and the concentrations of TNFα in serum were observed and measured on postoperative day 7. In treatment group, all above observation were done on postoperative month 4. Above all, determination of the effect of CTLA4Ig on preventing acute rejection and inducing tolerance in ROLT was observed.Results ①Recipients (no treatment group) died one by one within 6th～14th days; pathologic character of rejection in transplantation liver could be found; ② In treatment group, on postoperative day 7 and month 4, no clinical rejection character and no pathologic character of rejection in transplantation liver were found and serum concentration of cytokins related to TNFα found lower than that of contrast group(P＜0.05), and serum concentration of ALT、AST、TBIL、DBIL found lower too(P＜0.05); But serum concentration of TP and Alb was found higher than that of contrast group(P＜0.05). Conclusion ① CTLA4Ig treatment alone inhibits the rejection responce in ROLT. ② CTLA4Ig treatment can Prevent rejection and induce immune tolerance in ROLT model with characters of acute rejection; the serum concentration of cytokins related to TNFα can probably be used as evaluation standard of rejection in ROLT rejection.
Objective To investigate the expression of transcription factor Foxp3 in the orthotopic liver transplantation by using the inbred rats with spontaneous immune tolerance. Methods The model of orthotopic liver transplantation was established on inbred rats according to double-sleeve technique. The total RNA that was isolated from liver was reversely transcribed into cDNA. The method of real-time fluorescence quantitative PCR (RFQ-PCR) was used to analyze the expression level of Foxp3 mRNA in tolerance group and syngeneic group, respectively. The expression of Scurfin in hepatic tissue was assayed by Western blot and then was analyzed by computer imaging system. Results The expression levels of Foxp3 mRNA and Scurfin in the transplanted liver were significantly lower than those of normal liver within the first week after transplantation. The level of Foxp3 mRNA began to increase on day 7 and reached the peak point on day 14. The expression level of Foxp3 mRNA began to decrease on day 30 but was still higher than the normal value (P＜0.05). The Western blot showed resemble changes on that of Scurfin. Conclusion Transcription factor Foxp3 may play an important role in the spontaneous immune tolerance in the orthotopic liver transplantation of inbred rat.
Objective To investigate the role and mechanism of heat shock protein 60 (HSP60) in induction of murine skin allograft tolerance. Methods At the age of 8-12 weeks, inbred female BALB/C (H-2d) mice (n=45) and CBA/N (H-2k)mice (n=15) were used as transplantation donors and C57BL/6 (H-2b) mice (n=60) as recipients. Recipients C57BL/6 (H-2b) mice were randomized into 4 groups (n=15). In group A, 1 cm × 1 cm Wolfe-Krause skin graft was excised from the back of BALB/C (H-2d) mice and hypoderma was scraped off aseptically, and then transplanted to the back of C57BL/6 (H-2b)mice. The method of skin transplantation in the other 3 groups was the same as to group A. In group B, C57BL/6 (H-2b) mice were treated with imcompleted Freund’s adjuvant (IFA) administration into the back 2 weeks before transplantation of BALB/C (H-2d) mice skin. In group C, C57BL/6 (H-2b) mice were administered HSP60 emulsified in IFA into the back 2 weeks before transplantation of BALB/C (H-2d) mice skin. In group D, C57BL/6 (H-2b) mice were treated with HSP60 emulsified in IFA into the back and followed by skin transplantation of CBA/N (H-2k) mice 2 weeks later. The delayed type hypersensitivity was determined 7 days after transplantation. One-way mixed lymphocyte reaction, the concentration of cytokines in the mixed lymphocyte reaction culture supernatant was determined 7 days and 25 days after transplantation. The survival time of skin allograft was observed. Results The survival time of skin allograft in groups A, B, C and D was 12.4 ± 0.5, 11.6 ± 0.8, 29.3 ± 2.6 and 27.6 ± 2.1 days, respectively. There was significant difference between groups A, B and groups C, D (P﹤0.05), while there was no significant difference between group A and group B as well as between group C and group D (P gt; 0.05). The counts of per minute impulse (cpm) of mixed lymphocyte reaction 7 days after transplantation in groups A, B, C and D was 12 836 ± 1 357, 11 876 ±1 265, 6 581 ± 573 and 6 843 ± 612, respectively. There was significant difference between groups A, B and group C and group D (P lt; 0.05), while there was no significant difference between group A and group B as well as between group C and group D (P gt; 0.05). The cpm of mixed lymphocyte reaction at 25 days after transplantation in group A, B, C and D was 13 286 ±1 498, 12 960 ± 1 376, 11 936 ± 1 265 and 12 374 ± 1269, respectively. There was no significant difference among 4 groups (P gt;0.05).The concentration of IL-10 in the mixed lymphocyte reaction culture supernatant in groups C, D were higher than that in groups A, B, and IL-2 and IFN-γ were lower than that in groups A, B 7 days after transplantation (P lt; 0.05), while there was no significant difference between group A and group B as well as between group C and group D (P gt; 0.05). There was no significant difference in cytokines among the 4 groups 25 days after transplantation (P gt; 0.05). The delayed type hypersensitivity in groups A, B, C and D 7 days after transplantation was 0.84 ± 0.09, 0.81 ± 0.07, 0.43 ± 0.05 and 0.46 ± 0.03 mm, respectively. There was significant differences between groups A, B and groups C, D (P lt; 0.05). While there was no significant difference between group A and group B as well as between group C and group D (P gt; 0.05). Conclusion HSP60 may play a role in induction and maintenance of murine skin allograft tolerance.
Objective To study the immunological tolerance induced by blocking the second signal of T cell with extrinsic cytotoxic T lymphocyteassociated antigen 4 immuno globlin(CTLA4-Ig). Methods Fifty-four BALB/C mice, inbred strains, were employed as recipients of bone allografts, using a model of heterotopic muscle pouch. The 54 mice were divided into 3 groups and18 for each group. The first group, in which the donor was C57BL/6 with intraperitoneal injection ofL6(as a control), was named AL group. The second group,also C57BL/6 with injection CTLA4-Ig, was named AC group. The third group,homologous BALB/C with injection of PBS buffer solution, was named AB group.The serum antibody, lymphocyte proliferation of the second stimulation by splenic cell and bone supernatant of donor, the analysis of lymphocyte subsets, a regraft experiment and histology were determined 2, 4 and 6 weeks after transplantation. The second transplantation was to regraft C57BL/6(BC group) and C3H(BHgroup) mice respectively after first 12 mice being transplantated with C57BL/6 and injected with CTLA4-Ig as to detect donor-specificity of immunological tolerance. Results Compared with AB group, AL group created more intensive immune rejection: CD4 T cell subsets(Plt;0.05), the serum antibody(Plt;0.05) and lymphocyteproliferation of the second stimulation by splenic cell and bone supernatant ofdonor (Plt;0.01 and 0.05) were significantly increased. However, the results of AC group showed that CTLA4-Ig significantly inhibited the immune rejection: CD4T cell subsets(Pgt;0.05), the serum antibody (Pgt;0.05), and lymphocyte proliferation of the second stimulation(Pgt;0.05) were similar to those of AB group. Histological observation of AC group showed that lymphocyte infiltration disappeared,cartilage and new bone formed, and bone marrow cavities emerged. A regraft experiment showed that CD4 T cell subsets (Plt;0.05) and lymphocyte proliferation of the second stimulation by splenic cell and bone supernatant of donor(Plt;0.05), BC group was significantly lower than those of BH group. So theimmunological tolerance induced by CTLA4-Ig was of donor-specificity. Conclusion The immunological tolerance induced by CTLA4-Ig was prolonged for 6 weeks. This study provides a brand-new path for bone transplantation, which can be helpful to other organ transplantation.
ObjectiveTo evaluate the effect of pre-infusion of allogeneic lymphoyctes treated with 5-FU on the rat liver graft. MethodsRat liver transplant models from Wistar to SD were established. Four groups were designed as following: control group: only liver transplantation without any other intervention; lymphocytes group: 1 ml of untreated lymphocytes (5×106/ml) from Wistar rats were preinfused into SD rats on day 7 and 4 separately before transplantation; lymphocytes with low concentration of 5-FU group: low concentration 5-FU (7.5 μg) treated lymphocytes were preinfused as above; lymphocytes with high concentration of 5-FU group: high concentration 5-FU (15 μg) treated lymphocytes were preinfused as above. Fas-L and CD8 expression were detected by immunohistochemistry method on day 7 after transplantation. ResultsThe integral opticaldensity (IOD) of Fas-L positive lymphocytes in the lobules of liver and portal areas were higher in lymphocytes with low concentration of 5-FU group than in the other groups （Plt;0.05）. There was no difference between lymphocyte group and lymphocytes with high concentration of 5-FU group （Pgt;0.05）. The IOD of CD8+ expression in lobules of liver was not different among all the three lymphocytes treated groups （Pgt;0.05）. But in portal areas, CD8+ expression was lower in the lymphocytes with low concentration of 5-FU group than in the other groups （Plt;0.05）. ConclusionPreinfusion of lymphocytes treated with low concentration 5-FU can induce graft immune tolerance, the probable mecanism of which is the increasing Fas-L expression in graft.
Objective To summarize the role of costimulatory molecules in inducing immune tolerance of organ transplantation. Methods Domestic and international publications online involving costimulatory molecules and immune tolerance in recent years were collected and reviewed. Results The relationship between costimulatory pathways and transplantation immunity has already been clarified in recent years. The main costimulatory molecules alreadly found mainly include B7-CD28/CTLA4, CD40-CD154, 4-1BB/4-1BBL, and ICOS-B7h, etc. Costimulatory pathways com-inhibition or combining with other immunosuppression methods could obtain stable and long lasting immune tolerance. Conclusions With the development of immunology and molecular biology, costimulatory pathways of T lymphocyte activation will be further interpreted. Other new costimulatory molecules will be discovered in the future, which will afford theory evidence for inducing immune tolerance.
Objective To explore the effect of cytotoxic T lymphocyte-associated antigen 4 (CTLA4-Ig) fusion protein on the function of orthotopic liver allograft. Methods Orthotopic liver allograft models of rhesus monkeys were established in this study. The survival time, liver function and morphologic changes of graft were observed, respectively. The levels of IL-2 and IL-10 were detected by ELISA. Apoptosis was monitored by TUNEL.Results The average survival of control group was 6.57 d, while the average survival of CTLA4-Ig group was 14.92 d, which was statistically prolonged (Plt;0.05). Serum ALT level was highly increased, and Alb level decreased obviously in control group. While the levels of ALT and Alb kept in normal in CTLA4-Ig group. After day 3-7, the expressions of IL-2 were highly expressed in control group, while the expressions of IL-10 in CTLA4-Ig group were higher than those of control group. The severity of rejection reaction after day 3 was weaker in CTLA4-Ig group than that of control group by histological assessment. The apoptosis index after day 3 in the liver cells was highly increased in control group as compared with the CTLA4-Ig group. Conclusions CTLA4-Ig fusion protein therapy can induce immunotolerance and prolong the survival of recipients. The increasing of cytokines IL-2 or the decreasing of cytokines IL-10 may be one of the laboratory indexes in monitoring immunotolerance of transplantation.