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 observe the effect of transfer of immature mouse myeloid dendritic cells （DC） generated with low-dose granulocyte-macrophage colony-stimulating factor （GM-CSF） on cardiac allograft survival. Methods Mouse DC were generated with standard doses or low doses GM-CSF from bone marrow cells, the phenotype and functional properties of these DC were compared through fluorescence-activated cell sorting（FACS） analysis and mixed lymphocyte reaction（MLR）, 1. 0 × 106 DC generated with low doses GM-CSF were administered to the recipients 7 days before transplantation, and the cardiac allograft survival were observed. Results In contrast to DC generated with standard doses, DC generated with low doses were phenotypically immature DC （CD11c＋, CD80- , CD86- , MHCⅡlow）, and induced allogeneic T cell unresponsiveness, and administration of these DC to recipients prolonged cardiac allograft survival from 6.3±1.2 days to 14.3±1.9 days. Conclusions DC generated from mouse bone marrow progenitors in low doses of GM-CSF are phenotypically and functionally immature, and prolong cardiac allograft survival when they are administered 7 clays before transplantation.
【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 study the effect of allogeneic canine cord blood mesenchymal stem cells（cbMSC）transplantation on the distribution of CD4+T and CD8+T in infracted area of hearts. Methods Mononuclear cells of cord blood were isolated by density gradient centrifugation and amplified by adherent culture. 36 adult male dogs were divided into experimental group and control group. Animal models of acute myocardial infarction were established by ligating anterior descending coronary artery. The fourth generations of mesenchymal stem cells (MSC) were transplanted into infarcted area of hearts by left anterior descending coronary artery after 72h induced by 5-aza and transfected by LacZ. The survival of transplanted cells in hearts can be confirmed by βgal expression. CD4+T and CD8+T cells distributed in infarcted area were detected by immunohistochemical staining method. The ImagePlus 5.1 software was used to analyze the images. Results Cells transplanted into infarcted area could survive for a long time. 2, 4, 8 weeks after transplantation, the IOD of CD4+T in experimental group were 44.35±7.03, 19.29±4.11 and 20.27±3.51 respectively, and the CD4+T/CD8+T ratios were 0.63±0.12, 0.51±0.15 and 0.66±0.08. In control group, the IOD of CD4+T at 2, 4, 8 weeks after transplantation were 65.78±10.27, 28.02±2.59, 29.79±6.83, and the CD4+T/CD8+T ratios were 1.28±0.20, 1.34±0.09 and 1.50±0.16. The IOD of CD4+T and CD4+T/CD8+T ratio in experimental group were significantly lower than that in control group. In experimental group the IOD of CD8+T at 2, 4, 8 weeks after transplantation were 69.88±7.84 , 37.80±8.83 and 30.81±7.42, higher than that in control group which were 51.28±10.01, 20.87±4.50 and 19.91±2.87. Conclusion The preliminary results indicated that allogeneic cbMSC transplanted in infarcted area can escape from immune rejection, its mechanism may be associated withdecreasing the amount of CD4+T cells infiltrated in periphery of infarcted area and maintaining CD4+T/CD8+T ratios at a lower level.
ObjectiveTo investigate the relationship between peripheral T cell apoptosis and specific immune tolerance induced by T cell vaccination（TCV）. MethodsT cell vaccinations were made from the spleen cells of SD rats, which were induced by ConA and were challenged with the spleen cells of Wistar rats. Normal SD rats were vaccinated intraperitoneally with TCV (experimental group) or RPMI 1640 culture buffer (control group) respectively .Oneway mixed lymphocyte reaction (MLR) were performed,the apoptosis of peripheral T cell were assayed using flow cytometric analysis before and after vaccination.ResultsIn experimental group, the result of MLR showed that the response captivity of SD rat spleen cells were suppressed significantly after vaccination in comparison with prevaccination (Plt;0.01) and the percentage of peripheral T cell apoptosis was increased significantly after vaccination compared with prevaccination (Plt;0.01); In control group, there was no significant difference between prevaccination and postvaccination about MLR and peripheral T cell apoptosis. ConclusionT cell vaccination is capable of inducing Agspecific immune tolerance, the T cell apoptosis of peripheral blood induced by T cell vaccination may result in the depletion of Agspecific reactive T cells, which is vital in inducing specific immune tolerance.
Objective To summarize the advancement of immune tolerance in pancreas transplantation.Methods Relevant literatures about immune tolerance in pancreas transplantation, which were published recently domestic and abroad were collected and reviewed. Results The main methods to induce immune tolerance are peripheral tolerance and central tolerance. The induction of chimerism by infusion of donor-specific bone marrow cells is the research hot spot recently. Conclusion The infusion of donor-specific bone marrow cells in combination with one or more peripheral tolerance maybe can induce immune tolerance successfully. However, it should be researched further.
Abstract: Objective To investigate the phonetype and tolerogenic function of semimature dendritic cells (DC) transfected by myeloid differentiation marker 88（MyD88） small interfering ribonucleic acid（siRNA）. Methods Bone marrow of BALB/c mice was inoculated and cultured in vitro，and induced into DC by 10ng/ml recombinated granulocyte macrophage colony stimulating factor (rmGM-CSF) ，then DC was divided into three groups at the 8th day: blank control group: added nothing; lipopolysaccharide （LPS）group: added with 1μg/ml LPS; and experimental group: added with 1μg/ml LPS after transfected by MyD88 siRNA for 4 hours. The phonetype of three groups was analysed by fluorescenceactivated cell sorting (FACS). The concentration of interleukin 10（IL-10）and interleukin 12（IL-12） in culture supernatant was detected by enzyme linked immunosorbent assay（ELISA）.The function of stimulating alloreactive T cell roliferation were evaluated by primary and secondary mixed lymphocyte reaction （MLR）. The cardiac allograft survival time was compared after DC of three groups injected into recipient mice. Results The phonetype of blank control group DC was CD11c＋，CD25-，CD40low，CD80low，CD86low，MHC-Ⅱlow， which could be induced to mature DC by LPS. Experimental group DC was phonetypically semimature DC (CD11c＋，CD25－，CD40mid，CD80low，CD86low，MHC-IIid) and the IL-10/IL-12 ratio of semimature DC increases significantly. yporesponsiveness of alloactive T cells can be induced by experimental group DC and the survive time of heart allograft was prolonged. Conclusion Immature DC could become semimature DC after transfected by MyD88 siRNA and stimulation by LPS. These semimature DC are more tolerogenic than immature DC.
Objective To introduce the research progress in the immune of composite tissue allotransplantation. Methods The related articles were reviewed to summarize the immune characteristics, experimental developments, and cl inical experiences of composite tissue allotransplantation. Results Composite allogeneic tissue is on the body surface, including the composition of the complex with high antigenicity. There are a lot of differences in the immune responsesbetween composite tissue allotransplantation and organ transplantation, such as immunosuppressant protocol, rejectiondiagnosis, and chronic rejection. Conclusion In the next study, it is urgently needed to learn these experiences and toestabl ish the special standard of composite tissue allotransplantation in induction of immune tolerance, local medication, and rejection diagnosis.
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.