ObjectiveTo investigate feasibility, safety, and problems to be solved in treatment with programmed death receptor protein-1 (PD-1) monoclonal antibody for patients with recurrent liver cancer after liver transplantation (LT).MethodAll of the domestic and foreign cases reports about the application of PD-1 monoclonal antibody in the patients with recurrent liver cancer after the LT were analyzed and summarized.ResultsIn six patients with recurrent liver cancer after the LT who received the PD-1 monoclonal antibody, the acute graft rejections were observed in 3 patients, 2 patients had the progressive disease but there was no evidence of the graft rejection, 1 patient achieved the complete response and there was no evidence of graft rejection and no side effects.ConclusionsAt present, effect of PD-1 monoclonal antibody therapy is still not sure in patients with recurrent liver cancer after LT. If PD-1 monoclonal antibody is used off-label, close surveillance is needed to discovery possible acute graft rejection.
Objective To study whether the porcine endothelial cells (PECs) lines transfected by HLA-G1 can alter the lysis mediated by human peripheral blood mononuclear cell (PBMC) and natural killer cell 92(NK-92). Methods By use of liposomes pack, the pcDNA3.0 eukaryotic expression vector carrying HLA-G1 was transfected into PECs. Using indirect immunofluorescence and RT-PCR assays, the HLA-G1 expression in PECs was detected. The alteration of the lysis mediated by PBMC and NK-92 was detected by51Cr-release assays. Results HLA-G1 expression could be detected in PECs after transfection of HLA-G1 at the levels of protein andRNA. It also could be found that the survival rate of transfected PECs was muchhigher than that of non-transfected PECs, when both of them faced the lysismediated by human PBMC and NK-92.After transfecting the expression of HLA-G1 could be found in the transfected PECs and the lysis mediated by PBMC and NK-92 to PECs decreased obviously (Plt;0.05). Conclusion The PECs- transfected by HLAG1 can decrease the NK lysis, so that it may provide us a new thought to inhibit the xeno-cell-rejection.
ObjectiveTo observe the clinical effect of Rituximab combined with intravenous immunoglobulin (IVIG) in preventing blood group antibody mediated rejection (AMR) in pediatric ABO incompatible living donor liver transplantation (ABOi-LDLT).MethodsA total of 503 cases of pediatric living donor liver transplantation in Beijing Friendship Hospital Affiliated to Capital Medical University from June 2013 to December 2020 were retrospectively collected; the overall survival of recipient and graft were compared between ABOi-LDLT and ABO compatible living donor liver transplantation (ABOc-LDLT), and we summarized the data of AMR in 7 cases received Rituximab+IVIG protocol.ResultsThere were 53 cases of ABOi-LDLT and 450 cases of ABOc-LDLT in our study. The 5-year cumulative survival rate of recipients and grafts was 98.0% and 96.0% in the ABOi-LDLT group respectively, and in ABOc-LDLT group was 92.2% and 89.1% respectively, there was no significant difference between the two groups (P=0.232, P=0.381）. Seven children with blood group antibody titer >1∶64 were included in the study. On the basis of classical intensive immunosuppressive therapy, all patients were treated with Rituximab+IVIG. The blood group antibody titer of 6 patients remained stable, and no rejection occurred; one patient developed severe AMR and graft failure, and recovered after salvage treatment of ABOc-LDLT.ConclusionRituximab+IVIG can be used as an effective therapeutic option to prevent blood group AMR after ABOi-LDLT.
Objective To investigate the mechanism of hyperacute rejection (HAR) in pig to rhesus monkey vein xenograft. Methods Porcine femoral vein was transplanted into rhesus monkey. Deposits of IgM, IgG, C3 and C4 on the grafts were observed by immunoflurescence. Results Great deal of IgM, C3 and C4 were seen along the endothelium of donor vein, but IgG was not seen. ConclusionIn pig to monkey xenograft model, HAR is intiated by the binding of xenoreactive IgM to donor xenoantigens and followed by the activation of complement via the classical pathway.
OBJECTIVE: In the guinea pig-to-rat cardiac xenotransplantation model, the effect of complement depletion by using Chinese Cobra Venom Factor(CVF) on hyperacute rejection was evaluated. METHODS: Cardiac xenograft from guinea pig was transplanted into the abdomen of rat after the recipient being given i.p. a dose of CVF 0.20 microgram/g. the recipients were divided into group A (control group), group B (only given CVF), group C (CVF + Cytoxan + Splenectomy), group D (Cytoxan + Splenectomy) Cytoxan was injected into the abdominal cavity with a dose of 60 mg/Kg. The survival time of xenograft was measured and histologic observation was carried out after the cardiac arrest. RESULTS: The survival time of xenograft ranged from 15 to 3,120 minutes. There were significant difference among group A compared with group B and C (P lt; 0.01), and no difference between group A and group D, as well as group B and C (P gt; 0.05). There were significant difference between group B and D, as well as group C and D(P lt; 0.01). The histologic observation proved that the hyperacute rejection in group A and D was milder than group B and C. CONCLUSION: The study reveals that CVF can prolong the xenograft time by depleting complement activities and restricting hyperacute rejection in this model. Further basic and clinical study of effect of CVF in xenograft transplantation is worthwhile.
ObjectiveTo evaluate the effects and mechanism of indoleamine 2, 3-dioxygenase (IDO) modified rat bone marrow mesenchymal stem cells (BMSCs) in composite tissue allograft rejection. MethodsBMSCs isolated from Brown Norway (BN) rats (aged, 4-6 weeks) were infected by IDO[green fluorescent protein (GFP)]-lentivirus. The high expression target gene and biological activity cell line (IDO-BMSCs) were screened. IDO mRNA and protein expressions were detected by RT-PCR and Western blot. The biological activity of IDO in supernatant was detected by measuring the amount of kynurenine generation. In mixed lymphocyte reaction system, different numbers of IDO-BMSCs mixed with responding cells (peripheral blood mononuclear cell isolated from 4-6-week-old LEWIS rats, as recipient) and stimulating cells (peripheral blood mononuclear cell isolated from BN rats, as donor), with the cells ratios of 1:5:5, 1:10:10, 1:50:50, and 1:100:100 (as experimental groups 1, 2, 3, and 4, respectively). Each reaction system was blocked by 1 mmol/L 1-methyl-tryptophan (1-MT) (IDO specific inhibitor). IDO-BMSCs mixed with responding cells (1:5) as the negative control group, responding cells mixed with stimulating cells (1:1) as positive control group; and IDO-BMSCs were cultured in RPMI 1640 medium alone as blank control group. MTT assay was used to detect the T lymphocytes proliferation at 5 days. Furthermore, GFP-BMSCs (group A), IDO-BMSCs (group B), and normal saline (group C) were infused via the tail vein of allogeneic limb transplantation rats, and graft survival time and rejection were observed in each group. ResultsThe IDO expression of BMSCs after genetic modification was higher than that before genetic modification. IDO-BMSCs could significantly improved kynurenine concentration in culture medium supernatant when compared with GFP-BMSCs (P<0.05). Before adding 1-MT, with the ratio of IDO-BMSCs to responding cells decreased, T lymphocytes proliferation rate increased in experimental groups 1, 2, and 3, showing significant differences between groups (P<0.05); there was no significant difference between experimental group 4 and the positive control group (P>0.05). After adding 1-MT, T lymphocytes proliferation rate was significantly higher than that before adding 1-MT in the other experimental groups (P<0.05) except experimental group 4 (P>0.05). In vivo, IDO-BMSCs could promote colonization in allograft, inhibit transplantation rejection, and prolong survival time of composite tissue allograft; the survival time of composite tissue allograft was (11.5±0.6) days in group A, (14.5±0.8) days in group B, and (9.0±0.3) days in group C, and it was significantly longer in group B than in groups A and C, and in group A than in group C (P<0.05). ConclusionIDO-BMSCs can promote the survival of allogeneic composite tissue grafts in rats, and its mechanism may involve in inhibition of T lymphocytes proliferation and promotion their own colonization in allograft.
Objective To investigate the effect of interleukin-10 （IL-10） gene transfer on expression of CD44, selectin-E, lymphocyte function associated antigen-1 （LFA-1）, vascular cell adhesion molecule-1 （VCAM-1） in mice heart transplantation rejection. Methods Model of mice cervical heterotopic heart transplantation was set up, 96 mice were divided into three groups with random number table, control group： heart transplantation between C57 mice; transplant group： heart from BALB/C mice transplant to C57 mice; IL-10 group： IL-10 was transfected on BALB/C mice isolated heart for 1 hour, then transplanted to C57 mice. The messenger ribonucleic acid （mRNA） level expression of CD44 ,selectin-E ,LFA-1 ,VCAM-1 and IL-10 were measured by reverse transcription-polymerase chain reaction （RT-PCR） at the 5th day after transplantation. Results The mRNA level expression of CD44, selectin-E ,LFA-1 ,VCAM-1 in transplant group were significantly increased than those in control group （P〈0.01）. The mRNA level expression of CD44, selectin-E, LFA-1 ,VCAM-1 in IL-10 group were significantly decreased than those in transplant group （P〈0.01）. Conclusion IL-10 gene transfer is able to decrease the expression of CD44, selectin-E,LFA-1 ,VCAM-1 and suppress the heart transplantation rejection in mice.
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.
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.