Objective To investigate the expression of T cell receptor (TCR) Vβ8.3 gene on CD4+ T lymphocytes in the rats with experimental autoimmune uveoretinitis (EAU). Methods Eighteen Lewis rats were divided into EAU, complete Freund′s adjuvant, and the control group. Inter photoreceptor retinoid-binding protein (IRBP) R16 peptide was synthesized using Fmoc procedure for induction of EAU. Magnetic absorption cell sorting (MACS) me thod was used to isolate the CD4+T lymphocytes from the spleen of the rats. Flow cytometry was used to monitor the efficiency of isolation. The expression of TCR Vβ8.3 gene segment on CD4+T lymphocytes was determined by fluorescent quantitative polymerase chain reaction. Results EAU was successfully induced in the Lewis rats immunized with IRBP R16 peptide. The proportion of CD4+T lymphocytes isolated by means of MACS was statistically higher than that before isolation (P<0.001). The expression of TCR Vβ8.3 gene segment on CD4+ T lymphocytes in EAU rats was significantly higher than that in the control (P<0.05). Conclusions There is a predominant usage of antigen-specific TCR Vβ 8.3 gene in EAU rats induced by IR BP R16 peptide, which may serve as a target for immunotherapy of EAU. (Chin J Ocul Fundus Dis,2004,20:165-167)
OBJECTIVE To probe the possibility of direct transfer of exogenous gene into peripheral nerve and its following expression in vivo. METHODS The PCMV beta plasmid containing cytomegalovirus (CMV) promoter and Escherichia Coli (E. Coli), beta-Galactosidease (beta-Gal) structural gene (lacZ gene) was constructed and injected into the rabbit sciatic nerve. The control group was injected PBS solution. The injected nerves were sampled and tested by beta-Gal enzyme activity assay of the 5-bromo-4-chloro-3-indolyl-beta-D-galactoside and beta-Gal histochemical stain. RESULTS In the control group, no beta-Gal enzyme activity was detected in the different stages after operation, and beta-Gal histochemical stains showed positive. In the experimental group, enzyme activity could be detected from 2 days to 30 days after operation, and the histochemical stains showed negative. CONCLUSION The exogenous gene can be transferred into peripheral nerve and expressed with bioactivity, thus the gene therapy to accelerate the recovery of nerve is practical.
ObjectiveTo detect the induction of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production in immunostimulated retinal pigment epithelial (RPE) cells to seek for the supplying of the arginine, a substrate for NOS; as well as the effects of produced NO on the tight junction of RPE-J cells. MethodsRat′s RPE-J cells were treated with interferon-γ(INF-γ), tumor necrosis factor-α(TNF-α) and lipopolysaccharide (LPS), and Northern and Western blotting were applied to analyze the expression of the citrulline-NO cycle enzymes and related enzymes and the effect of dexamethasone and cyclic adenosine monophosphate (camp) on the expression of iNOS. Immunocytochemistry reaction and Western blotting were used to evaluate the effect of produced NO on the tight junctions of RPE-J cells.ResultsiNOS and argininosuccinate synthetase (AS) were highly induced at both mRNA and protection levels in immunostimulated RPE cells while arginiosuccinate lyase (AL) was not induced. NO was produced by cells after stimulation with TNFα, IFNγ and LPS. The induction of iNOS mRNA and the production of NO by these immunostimulated cells was further enhanced by cAMP. NO was produced from citrulline as well as from arginine. And the produced NO impaired the tight junction of RPE-J cells, decreased the production of tight junction related protein ZO-1.ConclusionIn activated RPE-J cells, citrullinearginine recycling is important for NO production, and the produced NO weakened the function of tight junction of RPE-J cells.(Chin J Ocul Fundus Dis, 2005,21:32-36)
An important index determination for clinical diagnosis of renal function is to assay the creatinine concentration in serum. In the analytical process applied with coupled-enzyme, the quality control of sarcosine oxidase (SOX) as a key enzyme is the first problem to be solved. In order to establish an efficient and laboratory-scale production of SOX, the recombinant sarcosine oxidase (r-SOX) gene was a high-level expression in E.coli induced with lactose on a large-scale fermentation in 300 L fermenter. The results suggested that the biomass concentration reached OD600 of 22 and the expression of recombinant sarcosine oxidase in E. coli accounted for about 25% of total soluble protein in culture after fermentation. The cell-free extract obtained from high pressure homogenizer was processed by selective thermal denaturation and then purified with Ni-Sepharose FF chromatography. The sarcosine oxidase with 97% purity, 25 U/mg specific activity and 92.4% activity recovery was obtained. The molecular weight with single peptide chain of 53 kD and 55 kD of recombinant sarcosine oxidase was assessed by SDS-PAGE in presence or absence of 2-mercaptoehanol and Sephacryl S-200 chromatography. This sarcosine oxidase was found to be a conjugated protein, yellow enzyme, which combined with FAD as prosthetic group by covalent linkage. The contaminant of catalase was not detected in the sample pool of this enzyme. In addition, a further test to the thermal stability of sarcosine oxidase was done. According to the above results, the development and utilization of this enzyme has been set up on a reliable foundation.
Objective To investigate proliferating cell nuclear antigen (PCNA) gene expression in retinal pigment epithelium (RPE) cells and inhibition of antisense oligonucleotides(AS-OND) encoding PCNA mRNA to gene expression and proliferation of RPE cells, so as to search for new genetic therapy way for pro1iferative vitreoretinopathy (PVR). Methods (1) Rabbit RPE cells cultured in vitro were detected for PCNA expression by streptoavidin-biotin-enzyme complex (SABC) immunohistochemistry at several times. (2) The liposome-mediated synthetic antisense oligodeoxynucleotides (AS-ODN) and sense oligodeoxynucleotides (S-ODN) encoding PCNA were delivered to the RPE cells at different concentrations, then PCNA expresstion were detected by immunohistochemistry. (3) Exposed to different concentrations of AS-ODN and S-ODN, growth activity and suppressive rate of RPE cells were measured by methyl thiazolyl tetrazolium (MTT) methods. Results (1) PCNA were expressed in RPE cells, culmination in 48 hours of culture. (2) PCNA expression were markedly suppressed in the RPE cells treated with 0.28 and 1.12 μmol/L PCNA AS-ODN. (3) 0.28 μmol/L and 1.12 μmol/L PCNA AS-ODN significantly inhibited proliferative activity of RPE cells in a dose-dependent manner, the arrest rates of cellular growth reached 53% and 81% respectively. Conclusion AS-ODN complementary to PCNA mRNA at some concentration can sequence-specifically suppress PCNA expression in RPE cells and cellular proliferative activity, and show potential application to further experimental study for PVR genetic medication. (Chin J Ocul Fundus Dis, 2002, 18: 231-233)
Objective To study the expression and its significance of bcl-2 associated death (bad) gene in human optic nerves from traumatic atrophic eyeballs. Methods The optic nerves from 8 normal human donor eyes and 31 traumatic atrophic eyes were studied by immunohistochemistry technique. Results Bad protein was positively expressed in the normal optic nerve myelin sheath and residual myelin portions of optic nerve tissues from traumatic atrophic eyes. The expression of bad protein in the residual portions of myelin sheath was stained significantly ber than that in normal optic nerves (P<0.05)。The pathological durations for ocular atrophy was not co-related with the quantites of expression of bad protein. There was no significant difference between pathogenic causes of ocular atrophies and the quantites of bad expression (P>0.05). Conclusion Bad might possess the function of promoting the optic nerve atrophy processes in traumatic atrophic eyes. (Chin J Ocul Fundus Dis, 2002, 18: 276-278)
Objective To investigate the transfection and expression of recombinant plasmid human vascular endothelial growth factor 165/pcDNA3. 1 (hVEGF165/pcDNA3. 1) in myocardial cells, and to build foundation for gene therapy and cell therapy of coronary artery disease (CAD). Methods Myocardial cells were cultured in vitro and transfected by hVEGF165/pcDNA3.1 with liposome; then transient expressed protein was detected by reverse transcriptase-polymerase chain reaction (RT-PCR), immunochemistry and Western blotting. Results A strap as hVEGF165 was obtained by RT-PCR, the protein of hVEGF165 was found in myocardial cells by immunochemistry and in supernatant by Western blotting. Conclusion The recombinant plasmid hVEGFI65/pcDNA3. 1 can be expressed in myocardial cells, and may be used in studying CAD by gene therapy and cell transplantation.
Objective To investigate the changes in the expression level of bone morphogenetic protein 2 (BMP2) in the bone callus of rats with femoral fracture and brain injury to explore the effect of the brain injury on the fracture healing and to explore the related mechanism. Methods Thirty-two 12 week old SD rats weighing 368±25 g were randomly divided into 4 groups of 8 rats in each. The rats in Group A had a femoral fracture and a brain injury for 1 week; the rats in Group B had a femoral fracture but without brain injury for 1 week; the rats in Group C had a fracture and a brain injury for 2 weeks; and the rats in Group D had a fracture but without brain injury for 2 weeks. Thus, Groups A and C were used as the femoral fracture and brain injury models, and Groups B and D as the pure femoral fracture models for the controlled study. After the X-ray films were taken, the bone callus was obtained 1 week and 2 weeks after operation, respectively. Then, the bone callus growth and its histology were examined with theHE staining, the expression and changes in the level of BMP-2 were examined with the immunohistochemical staining, and the level of BMP-2 mRNA was measured with the RT-PCR. Results The X-ray films showed that less bone callus formation was found in Group A, and the fracture line in Group B was clearer than that in Group A. There was a greater amount of callus in Group C, and the fracture line was blurred. Only a little bone callus formation was found in Group D. The HE staining indicated that more fibroblasts and early-stage chondrocytes were found in Group A; some fibroblasts in the fracture interspace and fewer early-stage chondrocytes in Group B; some newly-formed trabecular bone at the end of the fracture in Group C; but no trabecular bone formation in Group D. The immunohistochemical staining indicated that the positive expression of BMP2 was b in the cytoplasms of the fibroblasts, the mesenchymal cells, the vascular endothelial cells, the early-stage chondrocytes, and the osteoblasts. The number of the positive cells was greater in Group A than in Group B, with a higher color intensity. The number of the positive cells was greater in Group C than in Group D, with a higher color intensity. The percentages of the cells positive for BMP-2 in the callus were greater in Groups A and C (0.762%±0.052%,0.756%±0.079%)than in Groups B and D (0.702%±0.052%,0.672%±0.044%) at the same time point, ith a statistically significant difference (Plt;0.05). The RT-PCR analysis showed that the expression of BMP-2 mRNA in the callus in Groups A-D was decreased in sequence. There was a significantly higher level of the expression in Groups A and C(1.07±0.13,0.78±0.11) than in Groups B and D(0.91±0.12,0.61±0.08) at the same time point (Plt;0.05). Conclusion The brain injury can promote the fracture healing process, which is probably related to an increase in the expression level of BMP-2 after the brain injury.
Objective To study the prokaryotic expression of the anti-tumor associated glycoprotein-72 (TAG-72) singlechain fragment variable (scFv) antibody and its specific affinity to hepatocellular carcinoma cell lines and tissues. Methods The cDNA of anti-TAG-72 scFv antibody was inserted into pCANTAB5E to obtain phage vector anti-TAG-72 -scFv-pCANTAB5E. Isopropyl-β-D-thiogalactoside (IPTG) was used to induce the expression of anti-TAG-72 scFv antibody. SDS-PAGE and Western blot were used to identify the anti-TAG-72 scFv antibody. Human hepatocellular carcinoma cells were cultured, and TAG-72 was determined with the obtained scFv by immunohistochemistry in the cells and paraffin-embedded hepatocellular carcinoma tissues. Results SDS-PAGE and Western blot showed that the anti-TAG-72-scFv antibody was successfully expressed. Anti-TAG-72 scFv could bind to hepatocellular carcinoma cell lines SMMC7721, HepG2, and HHCC, but not to BEL7402, suggesting that SMMC7721, HepG2, and HHCC cells expressed TAG-72. For the 40 cases of hepatocellular carcinoma tissues, the positive rate of TAG-72 in stage Ⅰ and Ⅱ-Ⅲ was 23.08% (3/13) and 62.96%(17/27), respectively. While no TAG-72 expression was found in the 10 normal cases. TAG-72 expression was significantly different between hepatocellular carcinomas and normal tissues (Plt;0.05). Conclusions The prokaryotic expression of anti-TAG-72 scFv antibody is successfully achieved, and can be used to identify TAG-72 antigen. TAG-72 is highly expressed in hepatocellular carcinoma, but not in normal liver tissue, which may be suggested as cancer marker of hepatocellular carcinoma.
Objective To investigate the mRNA expressions of liver X receptor α (LXRα), farnesoid X receptor (FXR), steroid xenobiotic receptor (SXR) and liver receptor homolog 1 (LRH-1) gene in patients with cholesterol gallstone (CGS) disease in order to elucidate the biomolecular pathogenesis of gallstone formation. Methods Twenty-seven patients with CGS (CGS group) and 10 controls without gallstones (control group) were included in this study. Serum lipid composition (total cholesterol, triglyceride, high density lipoprotein cholesterol, apoprotein B, apoprotein A1), gallstone cholesterol concentration and biliary composition (cholesterol, bile salts, lecithin) were assayed. Biliary total lipid and cholesterol saturation index (CSI) were calculated. mRNA expressions of LRH-1, FXR, SXR and LXRα gene were determined by real-time polymorphism chain reaction. Results Serum high density lipoprotein cholesterol concentration was lower in CGS group than that in control group 〔(0.93±0.05) mmol/L vs (1.33±0.09) mmol/L, P<0.001〕 and serum apoprotein A1 was also lower in CGS group than that in control group 〔(1.19±0.05) g/L vs (1.36±0.06) g/L, P<0.05〕. There were no differences in serum total cholesterol, triglyceride and apoprotein B between two groups (Pgt;0.05). CSI was higher in CGS group than that in control group (1.17±0.02 vs 0.79±0.10), P<0.001. Biliary cholesterol was also higher in CGS group than that in control group 〔(7.96±0.39) mol% vs (5.26±0.89) mol%, P<0.01〕, while biliary total lipid was lower in CGS group than that in control group 〔(104.72±10.51) g/L vs (154.24±14.20) g/L, P<0.05〕. There were no differences in bile salts and lecithin between two groups (Pgt;0.05). Expression of LRH-1 gene was higher in CGS group than that in control group (14.18±1.80 vs 7.22±2.22), the difference was statistically significant (P<0.05). There were no differences in mRNA expressions of LXRα, FXR and SXR gene between two groups (Pgt;0.05). Conclusion CGS disease may be related to increased expression of LRH-1 gene.