Regulatory roles of rno-miR-30b-5p in expressions of IL-10 and TLR4 in rats with experimental autoimmune uveitis / 眼科新进展

Objective To investigate the regulatory role of rno-miR-30b-5p in the expressions of interleukin-10 (IL-10) and toll-like receptor 4 (TLR4) in uveitis.Methods Both IL-10 and TLR4 gene 3'UTR lucfferase vectors and relevant binding site mutant vectors were constructed.Further,both rno-miR-30b-5p mimics and reporter gene vector were co-transferred into 293 T cells to validate the fluorescent alterations of the reporter gene expression to detect the interactions between rno-miR-30b-5p and the related target genes.Moreover,an experimental autoimmune uveitis (EAU) model was induced with IRBP peptide emulsion in rats,and both lymph node and spleen were isolated on day 12 after EAU induction.In order to measure rno-miR-30b-5p levels and IL-1 0,TLR4 expressions in spleen and lymph node,quantitative PCR and ELISA techniques were applied.Results The results of double lucfferase reporter gene expression analysis showed rno-miR-30b-5p mimic apparently down-regulated the fluorescence intensity of both IL-10 and TLR4 in wild type cells.After the mutation of the target site,the fluorescence intensity of the mutant vector was significantly reduced,accompanied by a significantly statistical difference (all P ＜ 0.01).Moreover,animal results revealed the expressions of rno-miR-30b-5p were apparently decreased,whereas IL-10 and TLR4 were markedly increased in both lymph node and spleen (all P ＜ 0.05).Conclusion Target identification shows that rno-miR-30b-5p can obviously regulate the expressions of 3'UTR gene with either IL-10 or TLR4 gene fragment,though its regulation might not be through the predicted site.The down-regulated expression of rno-miR-30b-5p in both spleen and lymph node in EAU rats result in the up-regulated expressions of both IL-10 and TLR4,further influence the development of uveitis.This study paves a way for the modulation of microRNA on the occurrence and development of uveitis,and will provide a new insight on treating uveitis.

Construction of eukaryotic plasmid expressing human transforming growth factor beta-induced gene and its influence on human corneal epithelial cell / 中华实验眼科杂志

Background The human transforming growth factor beta-induced gene (TGFBI) is the first determined pathogenic gene to corneal dystrophy.But the molecular genetic mechanism is completely unknown.The study of concerning role of TGFBI is very important for us understand the physiological function of cornea,and the pathogenesis of corneal dystrophy.Objective The vector of human transforming growth factor beta-induced gene (TGFBI) in eukaryotic expression was constructed and transfected into the human corneal epithelial cells in order to explore its influence on the growth of human corneal epithelial cells.Methods Total RNA was extracted from normal donor cornea tissue and cDNA was obtained by reverse transcription.TGFBI cDNA was synthesized by reverse transcription-PCR and cloned into pCMV-N-HA vector and identified by sequencing with PCR and EcoRV,XhoI double restriction endonuclease.The cells were grouped into recombinant pCMV-N-HA-TGFBI plasmid group,pCMVN-HA plasmid group,non-transfected group and pGFP-C2 transfected group.The recombinant pCMV-N-HA-TGFBI plasmid was transfected to human corneal epithelial cells and identified by observing the expression of enhanced green fluorescence protein(EGFP) in the cells.The TGFBI mRNA and proteins were harvested from the cells for real-time PCR analysis and Western blot assay respectively in 58 hours after transfection.The growth of the transfected cells was assessed by Cell Counting Kit-8.The expressions of matrix metalloproteinase(MMP) and tissue inhibitors of matrix metalloproteinase (TIMP) proteins and their mRNA in transfected cells were detected using SYBR fluorescence realtime PCR analysis and Western blot assay.Results The sequencing result of pCMV-N-HA-TGFBI positive clone plasmid showed that amplified TGFBI eDNA inserted into the vector at the correct sequence.EGFP was expressed in transfected cells in 48 hours after transfer of pGFP-C2 with the transfer efficacy 70％.The expression intensity of TGFBI mRNA was significantly higher in recombinant pCMV-N-HA-TGFBI plasmid group compared with pCMV-N-HA plasmid group and non-transfected group,and TGFBI protein was expressed in recombinant pCMV-N-HA-TGFBI plasmid group.No significant difference was found in the A450value among recombinant pCMV-N-HA-TGFBI plasmid group,pCMV-N-HA plasmid group and non-transfected group ( F=3.34,P＞0.05 ).The mRNA level of MMP1,MMP3in the transfected cells was significant elevated but that of TIMP1 was declined in the recombinant pCMV-N-HA-TGFBI plasmid group compared with pCMV-N-HA plasmid group and non-transfected group (all P ＜ 0.05 ).Meanwhile,the expressions of MMP1,MMP3 and TIMP1 proteins appeared the same tendency( all P＜0.05).Conclusions Eukaryotic expression vector harboring human TGFBI eDNA can be successfully constructed and efficiently overexpressed in human corneal epithelial cells.TGFBI gene is involved in the physical and pathological conditions of human corneal epithelial cells by regulating the activity of MMP1,MMP3 and TIMP1.The results offer a new approach for the study of the role of TGFBI in pathogenesis of corneal transparency.

The inhibiting effect on rat C Ⅱ TA and MHC Ⅱ gene expression by plasmid vector-based RNAi technulogy / 中华微生物学和免疫学杂志

Objective To investigate the inhibitory effect on rat MHC Ⅱ transactivator (C Ⅱ TA) and MHC Ⅱ gene expression by plasmid vector-based RNAi technology. Methods According to C Ⅱ TA ge-netic information, three short hairpin RNA (shRNA) sequences were designed and the corresponding plas- mid vectors were constructed. Rat dendritic cell (DC) was transfected in vitro and rat spleen was transfected in vivo. Real time RT-PCR and flow cytometry were used to detect the expression of C Ⅱ TA and MHC Ⅱ in DC and spleen after transfection. Results C Ⅱ TA-shRNA plasmids were successfully constructed. Com-pared with control groups, the mRNA transcription levels of C Ⅱ TA and MHC Ⅱ and the expression level of MHC H were significantly inhibited in all three pC Ⅱ TA-shRNA experimental groups ( P < 0.01 ). There was positive correlation between the expression of C Ⅱ TA and MHC Ⅱ. Among the three shRNA groups, the first one showed the strongest inhibitory effect. Conclusion The expression of rat C Ⅱ TA and MHC Ⅱ can be obviously inhibited by plasmid vector of shRNA targeting C Ⅱ TA gene, which can be used for further investi-gation of gene therapy.

An enhancer/promoter combination strengthens the expression of blood-coagulation factor VIII in non-viral expression vectors

We explored the potential of fusion of hepatic locus control region 1 (HCR-1) with HCR-2 to express B-domain-deleted human factor VIII (FVIII) in four cell lines. B-domain-deleted human FVIII expression was controlled by HCR-1/HCR-2, followed by liver specific and ubiquitous promoters. Chimera enhancer HCR-1/HCR-2, followed by cytomegalovirus (CMV) promoter, gave 2-fold more FVIII expression in all cell lines (105.6 ± 2.8 for Hek-293, 68.8 ± 3.8 for HepG2, 34.8 ± 1.3 for CHO, and 27.2 ± 1.6 ng-mL-1-106 cells-1 for L.N.) when compared to the vector with CMV alone (54.8 ± 3.3 for Hek-293, 32.4 ± 1.2 for HepG2, 18.6 ± 1.1 for CHO, and 10.1 ± 1.7 ng-mL-1-106 cells-1 for L.N.). Elongation factor 1-α gene and human CMV promoters were more efficient than the promoters from the human α-1-antitrypsin gene, and fviii was less efficient in hepatic cell lines. HCR-1/HCR-2, followed by strong promoters, increases FVIII expression in vitro. Our results underscore the importance of cis sequences for enhancing in vitro FVIII expression; this may be helpful for designing new strategies to improve heterologous expression systems.

Progress in the research on the vector for mediating RNA interference in mammals / 基础医学与临床

RNA interference (RNAi) is a process to inhibit specific gene expression via the degradation of the target mRNA induced by the double strand RNA. The use of RNAi in mammals as a tool to study gene function has rapidly developed in recent years. Here we described the novel progress and applications of the vector for mediating RNAi in mammals.

The Transfection of Cytosine Deaminase Gene and the Cell Killing Effects of Administration of 5-Fluorocytosine in Colon Cancer Cell Lines

PURPOSE: Among cancer gene therapies, the aims to eliminate malignant cells using genes as drugs as substitutes for conventional therapy, the use of bacterial cytosine deaminase (CD) which can convert the nontoxic 5-fluorocytosine (5-FC) to toxic 5-fluorouracil (5-FU), has been reported to provide a useful system for the selective killing of gene- modified mammalian tumor cells. Recently the transfection and expression of the CD gene, and the toxicity of 5-FC in eukaryotic cells, have been reported in colon, prostate and breast cancers, as well as in glioblastomas. To evaluate the growth inhibition effects in WiDr and LoVo colorectal cancer cells, after CD gene transfection and 5-FC administration, for the selective killing of cancer cells. METHODS: WiDr and LoVo colon cancer cell lines were cultured and the absorbencies for the percentage survival, on days 2, 4, 6, 8, and 10 of the culture, estimated by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetra-zolium bromide (MTT) test. The experimental subjects were divided as follows; Group 1: administration of 5-FC only, Group 2: administration of 5-FU only, Group 3: administration of 5-FC after CD gene transfection using pCMV/CD-1 plasmid vector. Each experiment, on days 2, 4, 6, 8 and 10 of the culture after the administration of 5-FC or 5-FU concentration of 10, 100 and 1000 uM, was triplicated and calculated the mean with standard deviation. The bacterial CD gene was transfected into each cell lines, using the lipofectin method, and the transfection and expression of the CD protein identified with beta-galactosidase immunohistochemical staining and western blotting. The growth inhibition effects in group 3 were compared with those in group 1 and 2, and the bystander effects and cell recoveries, after finishing the 5-FC treatment, evaluated until day 20 of the culture. RESULTS: The calculated survival percentages by from the MTT tests in the WiDr and LoVo cells revealed 110~150% enhancing effects after the administration of 5-FC concentration of 10, 100 and 1000micro M (group 1), and 30~90% after the administration of 5-FU at the same concentrations (group 2), which were shown to be statistically significantly (P<0.001). After transfection of pCMV/CD-1 plasmid vector into the WiDr and LoVo cells using the lipofectin method, the transfection rate of the WiDr and LoVo cells were 4.2 +/- 0.6% and 13.8 +/- 0.8%, respectively. Also the CD protein, with the polyclonal anti-CD antibody, by western blot, revealed weak expression on day 2, followed by strong expression on day 4, which progressively decreased by days 6 and 8 in the WiDr cells. Conversely, the LoVo cells showed weak expression on day 2, which progressively increased by days 4 and 6, was followed by the strongest expression on day 8 in LoVo cells. About 60~85% significant growth inhibition effects (P<0.001) were revealed in group 3, with proportionally different effects, corresponding to the CD gene transfection rate, concentration of 5-FC and duration of the culture. The 60~85% growth inhibition effects were complex of the response to the transfection rate and the bystander effects of CD expressed cells to the CD non-expressed cells. CONCLUSION: From our results, the administration of 5-FC after CD gene transfection revealed statistically significant growth inhibition effects of 60~85%, which were complex of the effects of CD expressed cells and the bystander effects to the CD non-expressed cells, and proportionally corresponding to the transfection rate, the duration of the CD protein expression and the concentration of 5-FC.

The Transfection of Cytosine Deaminase Gene and the Cell Killing Effects of Administration of 5-Fluorocytosine in Colon Cancer Cell Lines

PURPOSE: Among cancer gene therapies, the aims to eliminate malignant cells using genes as drugs as substitutes for conventional therapy, the use of bacterial cytosine deaminase (CD) which can convert the nontoxic 5-fluorocytosine (5-FC) to toxic 5-fluorouracil (5-FU), has been reported to provide a useful system for the selective killing of gene- modified mammalian tumor cells. Recently the transfection and expression of the CD gene, and the toxicity of 5-FC in eukaryotic cells, have been reported in colon, prostate and breast cancers, as well as in glioblastomas. To evaluate the growth inhibition effects in WiDr and LoVo colorectal cancer cells, after CD gene transfection and 5-FC administration, for the selective killing of cancer cells. METHODS: WiDr and LoVo colon cancer cell lines were cultured and the absorbencies for the percentage survival, on days 2, 4, 6, 8, and 10 of the culture, estimated by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetra-zolium bromide (MTT) test. The experimental subjects were divided as follows; Group 1: administration of 5-FC only, Group 2: administration of 5-FU only, Group 3: administration of 5-FC after CD gene transfection using pCMV/CD-1 plasmid vector. Each experiment, on days 2, 4, 6, 8 and 10 of the culture after the administration of 5-FC or 5-FU concentration of 10, 100 and 1000 uM, was triplicated and calculated the mean with standard deviation. The bacterial CD gene was transfected into each cell lines, using the lipofectin method, and the transfection and expression of the CD protein identified with beta-galactosidase immunohistochemical staining and western blotting. The growth inhibition effects in group 3 were compared with those in group 1 and 2, and the bystander effects and cell recoveries, after finishing the 5-FC treatment, evaluated until day 20 of the culture. RESULTS: The calculated survival percentages by from the MTT tests in the WiDr and LoVo cells revealed 110~150% enhancing effects after the administration of 5-FC concentration of 10, 100 and 1000micro M (group 1), and 30~90% after the administration of 5-FU at the same concentrations (group 2), which were shown to be statistically significantly (P<0.001). After transfection of pCMV/CD-1 plasmid vector into the WiDr and LoVo cells using the lipofectin method, the transfection rate of the WiDr and LoVo cells were 4.2 +/- 0.6% and 13.8 +/- 0.8%, respectively. Also the CD protein, with the polyclonal anti-CD antibody, by western blot, revealed weak expression on day 2, followed by strong expression on day 4, which progressively decreased by days 6 and 8 in the WiDr cells. Conversely, the LoVo cells showed weak expression on day 2, which progressively increased by days 4 and 6, was followed by the strongest expression on day 8 in LoVo cells. About 60~85% significant growth inhibition effects (P<0.001) were revealed in group 3, with proportionally different effects, corresponding to the CD gene transfection rate, concentration of 5-FC and duration of the culture. The 60~85% growth inhibition effects were complex of the response to the transfection rate and the bystander effects of CD expressed cells to the CD non-expressed cells. CONCLUSION: From our results, the administration of 5-FC after CD gene transfection revealed statistically significant growth inhibition effects of 60~85%, which were complex of the effects of CD expressed cells and the bystander effects to the CD non-expressed cells, and proportionally corresponding to the transfection rate, the duration of the CD protein expression and the concentration of 5-FC.