Cholangiocarcinoma; Vascular endothelial growth factor; c-myc gene
Objective To study the mechanism of immune hyporesponsiveness of allograft rejection induced by transfusion nonpufsed allopeptide syngeneic immature dendritic cell (imDC) generated from recipient bone marrow progenitors and to explore a possible strategy for liver allograft protection in clinic. Methods Forty experimental rats were randomly divided into 4 group: control group, cyclosporine A (CsA) group, mature DC (mDC) group and imDC group. In control group, Wistar rats only received liver transplantation. In CsA group, Wistar rats underwent liver transplantation plus CsA treatment 〔10 mg/(kg·d)〕. In mDC group, recipient-derived mDC 1×106 were infused intravenously through the penile vein to Wistar rats. In imDC group, ImDC with the dose of 1×106 were injected into Wistar rats via the dorsum vein of penile. In each group, five recipients were killed on the 10th day after transplantation, the other five recipients were left to observe survival time. The levels of ALT, AST, TBIL, IL-2, IFN-γ, IL-4 and IL-10 were detected. The acute rejection and the expression of FasL/Fas in the grafts were detected by HE and immunohistochemical staining. Western blot was used to detect Scurfin protein expression of CD4+ CD25+ T cells. Results The median survival time of the liver allografts in CsA group and imDC group were significantly longer than that in control group and mDC group ( P < 0.05). The levels of ALT and TBIL in control group and mDC group were significantly higher than those in CsA group and imDC group ( P < 0.05). Compared with CsA group and imDC group, the levels of IL-2 and IFN-γ were higher but the levels of IL-4 and IL-10 were lower in control group and mDC group ( P < 0.01). Slightly or no rejection reaction was found in CsA group and imDC group ( P < 0.05). The Scurfin protein expressions of CD4+ CD25+ T cells of imDC group were significantly higher than those of other three groups. Conclusion Application of nonpufsed allopeptide syngeneic recipient-derived imDC is an effective way to induce immune hyporesponsiveness by blocking indirect recognition in rat liver transplantation model. Survival span is significantly prolonged by its protective effect. The mechanism of immune hyporesponsiveness induced by imDC transfusion might be involved in some aspects: T cell apoptosis, immune deviation of Thl/Th2 cytokine net and inhibition of T lymphocytes responsiveness by regulatory T cells.
ObjectiveTo investigate target gene therapy for hepatocellular carcinoma (HCC). MethodsHerpes simplex virus thymidine kinase (HSVTK) gene was inserted into the gene of AFP enhancer/ALB promoter with adenoassociated virus (AAV) plasmid (WAV2) as a carrier, and a hybrid plasmid pWAV2/AFPALB/HYTK was constructed. Besides, plasmid pEGFP1/AFPALB was also constructed. Two kinds of plasmids were transferred into AFP positive cells HepG2 and AFP negative cells 7721, SPC and 7901.ResultsIt was found that enhance green fluorescence protein could only be seen in AFP positive cells HepG2. 710 bp DNA was amplified only in AFP positive HepG2 cells.ConclusionPlasmid pWAV2/AFPALB/HYTK for HCC demonstrates specificity in vitro.
ObjectiveTo construct the recombinant adenovirus vector carrying antisense multidrug resistanceassociated protein (MRP) and transfect the human drugresistant hepatocellular carcinoma cell line(SMMC7721/ADM). MethodsThe fragment of MRP gene encoding 5′region was cloned reversely into the shuttle plasmid pAdTrackCMV, with the resultant plasmid and the backbone plasmid pAdEasy1,the homologous recombination took place in the bacteria and the recombinant adenoviral plasmid was generated. The adenoviruses were packaged and amplified in 293 cells. Then the cell line of SMMC7721/ADM was transfected with the resultant adenoviruses.ResultsThe recombinant adenovirus vector carrying antisense MRP was constructed successfully. The viral titer was 2.5×109 efu/ml, and more than 90% SMMC7721/ADM cells could be transfected when the multiplicity of infection(MOI) was 100. ConclusionThe recombinant adenovirus vector constructed by us could introduce the antisense MRP into the human drugresistant hepatocellular cell line effectively, which would provide experimental basis for the mechanisms and reversal methods of the multidrug resistance in human hepatocellular carcinoma.
ObjectiveTo clone full-length cDNA of rat galectin-9 and construct recombinant adenovirus granule containing rat galectin-9 gene. MethodsThe galectin-9 gene was amplified by RT-PCR from rat liver tissue and inserted orientationally into plasmid pDC316-GFP digested by restriction endonucleases NotⅠ and HindⅢ. The recombinant pDC316-GFP-galectin-9 shuttle plasmid was identified by PCR, restriction endonuclease digestion and sequencing, and then co-transfected with rescue plasmid pBHGlox△E1.3Cre into HEK-293 cells by liposome reagent. Recombinant adenovirus vector containing rat galectin-9 gene (Ad5-galectin-9) was generated by sitespecific recombination and confirmed by PCR, and then Ad5-galectin-9 was propagated in HEK-293 cells and purified. The infectious titer of viral stock was determined by TCID50 assay. ResultsConstruction of pDC316-GFP-galectin-9 shuttle plasmid was confirmed to be correct by PCR, restriction endonuclease digestion and sequencing. Construction of recombinant adenovirus Ad5-galectin-9 was confirmed to be correct by PCR. The infective titer of Ad5-galectin-9 was 1.4×109 U/ml. ConclusionRecombinant adenovirus vector containing rat galectin-9 gene (Ad5-galectin-9) is successfully constructed, which provides the foundation of further research on the function of galectin-9 gene.
ObjectiveTo explore perioperative management model of ABO-incompatible liver transplantation. MethodsThe clinical data of ABO-incompatible caderveric liver transplantions without urgency performed in our center from July 2006 to May 2010 were analyzed retrospectively. Four patients had received an ABO-incompatible graft: AB to O in three, AB to A in one. All the cases were diagnosed as end-stage liver disese, one of them was primary hepatocellular carcinoma. ResultsFour survived to now (11 to 19 months) without severe infections and acute rejections. Two experienced coagulative disturbance and one of them had a second exploration. One developed acute renal failure and recovered with help under continuous veno-venous hemofiltration. All the cases were given 20 mg basiliximab two hours before revascularization and on day 4 after operation respectively. Splenectomy was performed in three, intravenous immunoglobulin was given in all more than seven days. Isohemagglutinin titers were basically stable and not relevant to the clinical manifestations. Antibiotic prophylaxis and immunosuppression protocol was same as the ABO compatible transplants except a 3-month-delay for steroid withdrawal. ConclusionABO-incompatible liver transplantation could be performed with appropriate perioperative management, such as basiliximab induction, splenectomy, intravenous immunoglobulin administration, and routine immunosuppression.
【Abstract】ObjectiveTo construct a recombinant adeno-associated virus(rAAV2) vectors carrying the combined transcriptional regulatory sequences of α-fetoprotein enhancer and albumin promoter for the purpose of targeted gene therapy for hepatocellular carcinoma (HCC). MethodsThe fragment of combined transcriptional regulatory sequences of α-fetoprotein enhancer and albumin promoter was amplified through polymerase chain reaction (PCR) and cloned into the promoter site of pAAV-IRES-hrGFP instead of the CMV promotor in AAV Helper-Free System to construct the rAAV2 expression plasmid pAAV-IRES-hrGFP-EP. Then the packaging cell lines (HEK 293 cell) was co-transfected with the pAAV-IRES-hrGFP-EP together with the control plasmid pAAV-RC and pHelper in AAV Helper-Free System by means of lipofectamine.The recombinant adenoassociated virus vector(rAAV2-EP) carrying the combined transcriptional regulatory sequences of α-fetoprotein enhancer and albumin promoter was packaged and amplified in the HEK 293 cell. Then the viral titer was checked by GFP. ResultsThe recombinant adeno-associated virus vector(rAAV2-EP) carrying the combined transcriptional regulatory sequences of α-fetoprotein enhancer and albumin promoter was constructed successfully, the b green fluorescence was observed in HEK 293 cells under fluorescence microscope. The viral titer was 1.2×105. ConclusionConstruction of the recombinant adeno-associated virus vector rAAV2-EP driven by the combined transcriptional regulatory sequences of α-fetoprotein enhancer and albumin promoter would provide a sound basis and improved vector for targeted gene therapy for HCC.