Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:EXPT01586 (G418)
 2,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Congenital erythropoietic porphyria (CEP) is a genetic disease characterized by an overproduction and accumulation of porphyrins in bone marrow. The enzyme defect concerns uroporphyrinogen III synthase (UROIIIS), the fourth enzyme of the heme biosynthetic pathway. It is the most severe porphyria and the treatment is largely symptomatic: gene therapy would represent a great therapeutic improvement. As a step toward the development of an effective gene therapy, we have constructed two retroviral vectors, LUSN and pMFG-US (with and without the selectable marker Neo), containing a full-length human cDNA for UROIIIS. Recombinant retroviruses were obtained by transfection of the LUSN or pMFG-US plasmid into the amphotropic packaging cell line psi CRIP. For each construct, three different producing clones were selected for their high titer (LUSN) or for their ability to express the message at a high level (pMFG-US). In vitro amplification of genomic DNA from target tissue demonstrated the presence of vector sequences. Murine fibroblasts infected in vitro expressed the human enzyme efficiently, as indicated by RNA and enzymatic studies. Retroviral-mediated gene transfer was then used to introduce the UROIIIS cDNA into human deficient cells. Enzyme activity was increased from 2% (deficient fibroblasts) to 121-274% of the normal value for the different clones. Transduced cells selected with G418 presented an 18-fold increase in enzyme activity compared to the normal cells. Furthermore, high gene transfer rate into peripheral blood progenitor cells (PBPB) was documented by in vitro amplification (PCR). These results demonstrate the potential usefulness of somatic gene therapy for the treatment of CEP.
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PMID:Correction of the enzyme defect in cultured congenital erythropoietic porphyria disease cells by retrovirus-mediated gene transfer. 770 83

A variety of strategies have been attempted in the past to stably transduce natural killer (NK) cells with cytokine or other cellular genes. Here, we demonstrate the successful delivery of the interleukin-2 (IL-2) gene into two human NK cell lines, IL-2-dependent NK-92 and IL-2-independent YT, by retroviral transduction. An MuLV-based retroviral vector expressing human IL-2 and neor markers from a polycistronic message was constructed and transduced into a CRIP packaging cell line. By coincubation of NK cells with monolayers of CRIP cells or by using retrovirus-containing supernatants in a flow-through method, 10% to 20% of NK cells were stably transduced. Upon selection in the presence of increasing G418 concentrations, transduced NK cells were able to proliferate independently of IL-2 for more than 5 months and to secrete up to 5.5 ng/10(6) cells/24 h of IL-2. IL-2 gene-transduced NK-92 cells had an in vitro cytotoxicity against tumor targets that was significantly higher than that of parental cells and secreted interferon gamma (IFNgamma) and tumor necrosis factor alpha (TNFalpha) in addition to IL-2. Moreover, the in vivo antitumor activity of IL-2 gene-transduced NK-92 cells against established 3-day liver metastases in mice was greater than that of parental nontransduced NK cells. Stable expression of the IL-2 transgene in NK cells improved their therapeutic potential in tumor-bearing hosts. Thus, transduced NK cells secreted sufficient quantities of bioactive IL-2 to proliferate in vitro and mediated the antitumor effects both in vitro and in vivo in the absence of exogenous IL-2. These results suggest that genetic modification of NK cells ex vivo could be useful for clinical cancer therapy in the future.
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PMID:Stable transduction of the interleukin-2 gene into human natural killer cell lines and their phenotypic and functional characterization in vitro and in vivo. 957 23

The tetracycline family is composed of several molecules whose antibacterial properties are due to the fixation on the bacterial ribosomes. Among those, doxycycline is one of the most potent antibiotics for which additional features have been recently discovered. Doxycycline has been found to inhibit metalloproteinases, to decrease gelatinolytic and metastatic activities of cancer cells, to have a "chondroprotective" effect in inflammatory arthritides, and to have strong antimalarial properties. In this study, a murine retrovirus producing cell line (psi CRIP-pXT1) was incubated in variable concentrations of doxycycline. The retroviral titer of this cell line was measured by the ability to transfer resistance to G418 to NIH/3T3 cells. The retroviral titer was significantly decreased by 70% when the packaging cells had been incubated with 25 microM of doxycycline at 37 degrees C. The ID50 was around 8 micrograms/ml. Astonishingly, this effect was not observed at 32 degrees C. The mechanism of this effect is still to be determined. It may be useful to be aware of this effect for uncovering all of the possible antiviral qualities of doxycycline and its related molecules, such as glycylcyclines or anthracyclines.
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PMID:Antimurine retroviral effect of doxycycline. 992 79

It has been difficult to characterize murine bone marrow (BM)-derived mesenchymal progenitor cells (MPCs) because of contamination with hematopoietic cells. We took advantage of the rapid proliferation of MPCs after replating to enrich murine MPCs by transfection with a retroviral vector carrying both LacZ and the selective neomycin resistance (neoR) gene. Freshly harvested BM cells from mice were incubated with BAG retroviral vector produced by amphotropic psi-CRIP or ecotropic psi-CRE producer cells for 48 hours and grown in the presence of G418.Cells incubated in psi-CRIP supernatant formed colonies composed of large homogeneous cells that were free of CD45(+) cells, but cells incubated in psi-CRE supernatant did not form stromal cell colonies. In the undifferentiated state, the cells displayed a fibroblast-like phenotype with low alkaline phosphatase activity. However, upon treatment with dexamethasone or 5-azacytidine, the retrovirally transduced cells differentiated into oil-red-O-positive adipocytic cells and osteogenic cells generating von Kossa-positive bone nodules. Osteogenic supplements composed of beta-glycerophosphate, dexamethasone, and ascorbic acid induced an increase in alkaline phosphatase activity and acute osteogenesis associated with early cell detachment. Subcutaneous injection with retrovirally transduced cells into day 1 newborn mice of the same strain produced ectopic calcium depositions surrounded by X-gal(+) cells. Retroviral selection of cycling adherent cells is an effective approach for enrichment of MPCs.
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PMID:Selection, enrichment, and culture expansion of murine mesenchymal progenitor cells by retroviral transduction of cycling adherent bone marrow cells. 1114 68