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CMV Promoter (cmv + promoter)
Selected AbstractsHyperalgesic effects of ,-aminobutyric acid transporter I in miceJOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2003Jia-Hua Hu Abstract The present study focused on the involvement of ,-aminobutyric acid transporter I (GAT1) in pain. We found that GABA uptake was increased in mouse spinal cord at 20 min and 120 min after formalin injection and in mouse brain at 120 min, but not 20 min, after formalin injection. In addition, the antinociceptive effects of GAT1-selective inhibitors were examined using assays of thermal (tail-flick) and chemical (formalin and acetic acid) nociception in C57BL/6J mice. The GAT1-selective inhibitors, ethyl nipecotate and NO-711, exhibited significant antinociceptive effects in these nociceptive assays. To study further the effects of GAT1 on pain, we used two kinds of GAT1-overexpressing transgenic mice (under the control of a CMV promoter or a NSE promoter) to examine the nociceptive responses in these mice. In the thermal, formalin, and acetic acid assays, both kinds of transgenic mice displayed significant hyperalgesia after nociceptive stimuli. In addition, the , opioid receptor antagonist naloxone had no influence on nociceptive responses in wild-type and transgenic mice. The results indicate that GAT1 is involved in the regulation of pain processes, and point to the possibility of developing analgesic drugs that target GAT1 other than opioid receptors. © 2003 Wiley-Liss, Inc. [source] Photochemical Internalization of Transgenes Controlled by the Heat-shock Protein 70 PromoterPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2006Lina Prasmickaite ABSTRACT Photochemical internalization (PCI) is a targeting technique that facilitates endosomal escape of macromolecules, such as transgenes, in response to photochemical treatment with endosome/lysosome-localized photosensitizers, such as disul-fonated meso-tetraphenylporphine (TPPS2a). In gene therapy this leads to enhanced transgene expression. Moreover, photochemical treatment generally activates transcription of stress-response genes, such as heat-shock proteins (HSPs), via stimulation of corresponding promoters. Therefore, we used HSP70 (HSPp; a promoter from the HSP family gene) and investigated whether the PCI stimulus could also activate HSPp and thereby stimulate transcription (expression) of the HSPp-controlled transgene internalized via PCI. Using human colorectal carcinoma and hepatoma cell lines in vitro, we showed that TPPS2a -based photochemical treatment enhances expression of cellular HSP70, which correlated with a photo-chemically enhanced expression (approximately 2-fold, at PCI-optimal doses) of the HSPp-controlled transgene integrated in the genome. Furthermore, PCI enhanced expression of the HSPp-controlled episomal transgene delivered as a plas-mid. However, in plasmid-based transfection, PCI-mediated enhancement with HSPp did not exceed the enhancement achieved with the constitutive active CMV promoter. In conclusion, we demonstrated that the PCI-relevant treatment initiates HSP70 response and that the HSP70 promoter can be used in combination with PCI, leading to PCI-enhanced expression of the HSPp-controlled transgene. [source] Development and characterization of a synthetic promoter for selective expression in proliferating endothelial cellsTHE JOURNAL OF GENE MEDICINE, Issue 4 2006P. Szymanski Abstract Background Systemic administration of non-viral gene therapy provides better access to tumors than local administration. Development of a promoter that restricts expression of cytotoxic proteins to the tumor vasculature will increase the safety of the system by minimizing expression in the non-dividing endothelial cells of the vasculature of non-target tissues. Methods Cell cycle promoters were tested for selective expression in dividing cells vs. non-dividing cells in vitro and promoter strength was compared to the cytomegalovirus (CMV) promoter. Successful promoter candidates were tested in vivo using two proliferating endothelium mouse models. Ovarectomized mice were injected with estradiol prior to lipoplex administration and expression levels were measured in the lungs and uterus 4 days after administration. The second model was a subcutaneous tumor model and expression levels were measured in the lungs and tumors. For both animal models, expression levels from the proliferating endothelium promoter were compared to that obtained from a CMV promoter. Results The results showed that the Cdc6 promoter yielded higher expression in proliferating vs. non-proliferating cells. Secondly, promoter strength could be selectively increased in endothelial cells by the addition of a multimerized endothelin enhancer (ET) to the Cdc6 promoter. Thirdly, comparison of expression levels in the lungs vs. uterus in the ovarectomized mouse model and lungs vs. tumor in the mouse tumor model showed expression was much higher in the uterus and the tumor than in the lungs for the ET/Cdc6 promoter, and expression levels were comparable to that of the CMV promoter in the hypervascularized tissues. Conclusions These results demonstrate that the combination of the endothelin enhancer with the Cdc6 promoter yields selective expression in proliferating endothelium and can be used to express cytotoxic proteins to treat vascularized tumors. Copyright © 2006 John Wiley & Sons, Ltd. [source] Hybrid promoters directed tBid gene expression to breast cancer cells by transcriptional targetingBIOTECHNOLOGY PROGRESS, Issue 2 2010Samila Farokhimanesh Abstract Developing cancer gene therapy constructs based on transcriptional targeting of genes to cancer cells is a new and promising modality for treatment of cancer. Introducing truncated Bid (tBid), a recently known member of the Bcl-2 family, eradicates cancer cells efficiently. For transcriptional targeting of tBid, two dual-specificity promoters, combining cancer specific core promoters and response modules, were designed. These two core promoter modules contained cancer specific promoters of MUC1 and Survivin genes accompanied by hypoxia-responsive elements and estrogen responsive elements (microenvironment condition of breast cancer cells) which were employed to achieve a higher and more specific level of tBid expression in breast cancer cells. Correlation of the level of tBid expression in normal and cancer cell lines with promoter activity was measured by RT-PCR after treatment with hypoxia and estrogen. The level of tBid expression under control of new hybrid promoters was compared with its expression under control of cytomegalovirus (CMV) promoter as a control. Our data revealed that the level of tBid expression in breast cancer cells were nearly 11 times more than normal cells because of the cancer specific promoters, although tBid expression under control of CMV promoter was almost the same in normal and cancer cell lines. Increased apoptosis was detected in the transfected breast cancer cell lines by the Caspase-3 activity assay. The application of these promoters may prove to have the advantage of tumor selective gene therapy in breast cancer cells and low-potential toxicity for normal tissues. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] High-Level Expression of Proteins in Mammalian Cells Using Transcription Regulatory Sequences from the Chinese Hamster EF-1, GeneBIOTECHNOLOGY PROGRESS, Issue 3 2004Jennifer Running Deer High-level expression of a recombinant protein in Chinese hamster ovary (CHO) cells typically requires the laborious and time-consuming procedure of stepwise gene amplification. We hypothesized that use of transcription control regions from a highly expressed gene in CHO cells to drive expression of a gene of interest might reduce the requirement for gene amplification. To this end, we cloned a 19 kb DNA fragment containing the Chinese hamster elongation factor-1, (EF-1,) gene, as well as 12 kb of 5, flanking sequence and 4 kb of 3, flanking sequence. Expression vectors containing 5, and 3, flanking sequences from the Chinese hamster EF-1, (CHEF1) gene were constructed and, after insertion of six different reporter genes, transfected into CHO cells. For comparison, CHO cells were also transfected with the same six reporter genes inserted into commercial vectors utilizing either the immediate early promoter from cytomegalovirus (CMV) or the human EF-1, promoter. The striking result from these studies was that average expression levels from pooled, stable transfectants of CHEF1 vectors were 6- to 35-fold higher than expression levels from commercial vectors that utilize the CMV or the human EF-1, promoters. We also used a CHEF1 vector to express a secreted and a membrane-bound protein in stably transfected non-CHO cell lines. CHEF1-driven expression of secreted alkaline phosphatase (SEAP) in three of four cell lines tested (HEK 293, K562, L1.2, and HCT 116) was 13- to 280-fold greater than that from a commercial vector employing the CMV promoter. After transfection of four different cell lines of hematopoietic origin (K562, L1.2, JY, and Jurkat), the CHEF1 vector was found to express the chemokine receptor CCR4 at >10-fold higher levels than that driven from a commercial vector utilizing the CMV promoter. Results from these experiments suggest that the CHEF1 vectors will be useful for high-level protein expression not only in CHO cells, but also in a variety of other mammalian cell lines. [source] 4135: Matrix metalloproteinase 14 overexpression reduces corneal scarringACTA OPHTHALMOLOGICA, Issue 2010S GALIACY Purpose Corneal wound healing is an everyday preoccupation for ophthalmologists.Corneal transparency depends on the scarring quality after a traumatic corneal wound, but also after refractive corneal surgery. Cicatrisation and fibrosis formation involve epithelial/fibroblast interactions via paracrin signals inducing extracellular matrix (ECM) remodelling. The major event is fibroblast activation and differentiation into myofibroblasts. These cells have a key role in the fibrotic response. They acquire contractile properties, and synthetise a new ECM, mainly composed of type III collagen. This scar tissue is less organised than the regular stroma, thus explaining corneal opacity. ECM remodelling is a critical step which aims to digest the excess of ECM by proteolysis of type III collagen. MMP14 is a membrane-bound fibrillar collagenase from the Matrix Metalloprotease family. We hypothesised that its overexpression in the corneal stroma during wound repair will increase ECM remodelling and thus prevent collagen deposition in the scar tissue. Methods We developed an adeno-associated virus-based vector expressing murine MMP14 under the control of the CMV promoter. We evaluated MMP14 overexpression after viral transfection in a murine model of corneal wound healing. We characterised several parameters: clinical observation, histology, and wound healing markers. Results Our preliminary results showed a decreased in oedema and corneal scar formation, associated with a decreased expression of alpha smooth actin and type III collagen. Conclusion These results represent proof of concept that gene transfer of MMP14 can reduce scar formation, which could have therapeutic applications after corneal trauma. [source] Development of lentiviral vectors for gene therapy for Usher syndrome type 1BACTA OPHTHALMOLOGICA, Issue 2007T HASHIMOTO Purpose: Usher 1B, one of the major subtypes of a combined blindness and deafness disease, is caused by mutations in the MYO7A gene, which encodes a large unconventional myosin expressed in the retinal pigment epithelium (RPE) and photoreceptor (PR) cells. This study aims at developing viral vectors expressing the wild type human MYO7A at an adequate level in order to rescue cellular phenotypes of MYO7A mutation. Methods: The full-length (7 kb) human MYO7A cDNA was cloned into the third generation, self-inactivating lentiviral vector under different promoters and enhancers. Human genomic 4-kb DNA fragment including exon 1 through 2 was cloned by PCR. Activities of different promoters and enhancers were tested by reporter assays using ARPE-19 cells. Previously identified Myo7a-null phenotypes in shaker-1 mouse were used to test the efficacy of various lentiviruses. Results: Lentiviral vectors could successfully transduce large genes (up to 7.6 kb) in vitro and in vivo for the purpose of gene therapy. Reporter assay indicated that regions with a suppressor activity and an enhancer activity existed within intron 1. The CMV promoter drove excessive MYO7A expression in the RPE, and thus caused cell death. A chimeric promoter that consists of partial CMV promoter with 160-bp MYO7A enhancer could direct moderate levels of gene expression in RPE and PR in vivo, and rescued a number of phenotypes in the mutant mice. Conclusions: These results illustrate the importance of regulating transgene expression levels in achieving therapeutic outcomes. They demonstrate the efficacy of lentivirus-mediated expression of the large MYO7A cDNA as a gene therapy strategy for correcting the MYO7A deficiency underlying Usher 1B. [source] UV-enhanced Expression of a Reporter Gene is Induced at Lower UV Fluences in Transcription-coupled Repair Deficient Compared to Normal Human Fibroblasts, and is Absent in SV40-transformed Counterparts,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2000Murray A. Francis ABSTRACT UV irradiation enhances transcription of a number of cellular and viral genes. We have compared dose responses for alterations in expression from reporter constructs driven by the human and murine cytomegalovirus (CMV) immediate early (IE) promoters in cells from patients with deficiencies in nucleotide excision repair (complementation groups of xeroderma pigmentosum and Cockayne syndrome) following UV exposure, or infection with UV-damaged recombinant vectors. Results suggest that unrepaired damage in active genes triggers increased reporter activity from constructs driven by the CMV promoters in human fibroblasts. Similar to human fibroblasts, HeLa cells and cells from Li,Fraumeni syndrome patients (characterized by an inherited mutation in the p53 gene) also displayed an increase in reporter activity following UV exposure; however, this response was absent in all simian virus 40 (SV40)-transformed cell lines examined. This suggests that a pathway affected by SV40-transformation (other than p53) plays an essential role in UV-enhanced expression from the CMV IE promoter. [source] | ||||||||||