Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Murine RSV-M glioma cells were genetically labeled with a retroviral BAG vector carrying the Escherichia coli beta-galactosidase gene. The X-gal-positive stable cell line RSV-M/BAG was obtained by the FDG-FACS method. To examine the behavior of glioma cells in the brain, we homografted RSV-M/BAG cells into the brain of C3H/HeN mice as cell suspensions. Individual grafted glioma cells were easily detected by histochemical staining for B-galactosidase (beta-gal). Three days after grafting, the beta-gal-positive cells were mainly found in the subependymal zone of the lateral ventricle. In addition, some solitary labeled cells were found at locations distant from the injection sites. On the seventh day after implantation, tumor masses were observed and graft-derived glioma cells were migrating bilaterally along the fibers in the corpus callosum. Other labeled cells extended into the brain parenchyma via the perivascular (Virchow-Robin) spaces. Rapid and extensive migration of individual glioma cells was thus clearly demonstrated by intracerebral transplantation of RSV-M/BAG cells.
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PMID:Migration of genetically labeled glioma cells after implantation into murine brain. 793 73

The skeletal muscle capillary bed may be an ideal recipient site for transplantation of genetically modified autologous endothelial cells and thus provide a basis for a technique of somatic gene therapy that would be applicable to a variety of acquired and inherited human diseases. The purpose of this study was to test the hypothesis that adhesion of lac-Z-transduced microvascular endothelial cells (MVEC) in the skeletal muscle capillary bed in vivo is dependent on the duration of arterial occlusion after injection of the transduced MVEC. MVEC derived from the abdominal fat pad of syngeneic rats (Wistar F-455) were transfected with the BAG vector, a replication-incompetent retroviral vector containing the lac-Z gene for beta-galactosidase and the Tn5 gene for selection of the transduced cells by the neomycin analogue, G418. lac-Z-transduced MVEC were radiolabeled with 125I-PKH-95, and, after the femoral artery was occluded for 10 min, these cells (1 to 2 x 10(6)) were injected intraarterially into the rat hindlimb. In the experimental groups the femoral artery clamp was removed at 0, 60, or 120 min after injection. A control group without pre- or postinjection femoral arterial occlusion was also studied. Adhesion of MVEC in the skeletal muscle capillary bed (mean percentage of injected 125I activity) was determined in groups of 4 rats at 1 day, 1 week, and 1 month after injection. Adhesion of the transduced MVEC did not increase as the duration of femoral artery occlusion after injection was increased.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Transplantation of lac-Z-transduced microvascular endothelial cells into the skeletal muscle capillary bed of the rat hindlimb occurs independent of the duration of femoral artery occlusion after injection of cells. 799 42

Gene transfer using retroviral vectors requires cell replication for insertion of the DNA provirus. Since the mitotic index of the mammalian kidney is very low, renal tubular cell replication was induced in adult rats as part of a regenerative response to the nephrotoxic injury induced by an intraperitoneal injection of folic acid. At 48 h, at the time of maximum 3H-thymidine incorporation, the left kidney was directly injected with a suspension of the Psi2 BAG retrovirus which transduces the beta-galactosidase gene. At 1-7 weeks after virus administration the left kidney was harvested. Using the polymerase chain reaction to amplify viral DNA, successful gene transfer was achieved in 8 of 15 kidneys. In 6 of 10 kidneys assessed histochemically positive staining for beta-galactosidase activity was detected in the cytoplasm of tubular epithelial cells. There was no evidence of gene expression in glomerular, vascular or endothelial cells. All analyses were negative in vehicle-injected kidneys and in the kidneys of animals which did not receive pretreatment with folic acid. These studies demonstrate the feasibility of gene transfer into the adult kidney provided that replication of specific cell types can be achieved.
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PMID:Gene transfer into the mammalian kidney: direct retrovirus-transduction of regenerating tubular epithelial cells. 808 52

We have labelled precursor cells in the embryonic rat cerebral cortex using BAG, a retroviral vector that expresses beta-galactosidase. We had previously reported that labelled precursor cells generate clusters of labelled cells that could be classified into four types by their morphological appearance and anatomical distribution (Price and Thurlow, 1988). In this study, we have used immunohistochemistry and intracellular dye labelling to identify the cell types that make up these clusters. We discovered that clusters are almost always composed of a single cell type. In addition to clusters composed entirely of neurones, we found four different types of glial cell clusters. In the grey matter, glial clusters are composed either of protoplasmic astrocytes, or of cells that have an astrocyte morphology, but no glial filaments. In the white matter, clusters are composed of either fibrous astrocytes or oligodendocytes. Our results indicate that each of these different cortical cell types is generated from a separate population of precursor cells.
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PMID:Multiple restricted lineages in the embryonic rat cerebral cortex. 833 May 26

To study minimal residual disease (MRD) in leukemia, we transferred the Escherichia coli genes encoding beta-galactosidase (lacZ) and neomycin resistance (neo(r)) into the subline LT12 of the Brown Norway rat acute myelocytic leukemia (BNML), employing the retroviral BAG vector. In this way leukemic cells were genetically marked. Ten independent cell lines were characterized during in vitro growth as well as during two subsequent in vivo passages for expression of neo(r) for which the neomycin analogue G418 was used, and for lacZ expression for which the substrate 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal) was used. Out of 10 lines, four revealed permanent high expression of lacZ in all cells. In four other lines greatly varying lacZ expression between the individual cells from these lines was observed. In the remaining two lines lacZ expression was gradually lost. In contrast, neo(r) expression was gradually lost in eight out of the 10 lines, particularly rapidly during in vivo passaging. In the remaining two lines neo(r) expression was retained. The genetic modification did not alter the in vitro leukemogenicity of the cells. Long term in vivo expression of neo(r) and lacZ was followed in two selected lines up to 12 subsequent passages, i.e. one from the group of homogeneous high lacZ expression and one from the group of heterogeneous lacZ expression. In both lines lacZ expression was retained whereas neo(r) expression was rapidly lost after the third passage. The feasibility of using genetically marked leukemic cells for studies of minimal residual disease (MRD) was explored by injecting rats with leukemic cells, treating them with chemotherapy at full blown leukemia development to reduce the tumor load, mimicking the induction of a state of MRD and studying lacZ expression at relapse. LacZ expression was evident in 100% of the cells whereas neo(r) expression was lost in a considerable fraction. These results indicate that the viral vector BAG can be used to mark leukemia cells genetically although a selection of clones with the desired stability of long-term expression is required.
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PMID:Retrovirus-mediated transfer and expression of marker genes in the BN rat acute myelocytic leukemia model for the study of minimal residual disease (MRD). 841 72

In the present report, we show prolonged expression of beta-galactosidase (beta-Gal) in the acinar cells of the submandibular and sublingual glands of rats following retrograde ductal injection of the retroviral vector BAG. To facilitate integration of viral DNA, cell division in the gland was induced by the administration of the beta-adrenergic agonist isoproterenol prior to the delivery of the vector. The frequency of cells stained for beta-Gal was higher if the virus was injected 4-20 hr after the two injections of isoproterenol given 24 hr apart than after the injection of only one dose of the drug. Without stimulation of cell division, no integration of the viral DNA was observed. Expression of the marker enzyme was observed up to 43 days, the limit of the observation period. The data indicate that salivary glands are potential targets of retrovirus-mediated gene transfer for somatic gene therapy.
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PMID:Retrovirus-mediated gene transfer into salivary glands in vivo. 884 86

We have studied the effects of sodium butyrate (NaBu) on the expression of genes transduced by retroviral vectors and stably expressed in two salivary gland-derived cell lines, A5-DAP and A5-BAG, established earlier. These cell lines were obtained by infecting A5 cells with the retroviral vectors DAP and BAG, respectively, and by selecting neomycin-resistant transduced cells. A5-DAP cells express human placental alkaline phosphatase (PLAP) and A5-BAG cells bacterial beta-galactosidase, both under the control of the viral long terminal repeat (LTR) enhancer-promoter. NaBu in the concentration of 2-8 mM inhibited the growth of A5-DAP cells, and induced the expression of heat-stable PLAP. These effects of NaBu were dose-dependent. Induction of PLAP in clones of A5-DAP cells that express different basal levels of the enzyme was not correlated with the relative inducibilty by NaBu. Exposure to 4 mM NaBu for 48 h increased the PLAP mRNA level by 31%. A5-DAP cells released, in a time-dependent manner, PLAP into the culture medium. Cells treated with NaBu released more PLAP than untreated cells in proportion to their elevated level of the enzyme. The parent A5 cells also express a low level of tissue non-specific type alkaline phosphatase, which was also induced by NaBu. NaBu inhibited the growth of A5-BAG cells also, and increased the beta-galactosidase level. These data indicate the genes transduced by retroviral vectors can be induced by NaBu, which most likely interacts with the viral LTR.
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PMID:Effect of sodium butyrate on the expression of genes transduced by retroviral vectors. 954 67

Both retro- and adenovirus-mediated gene therapy have been suggested as a novel approach to the treatment of malignant brain tumors. However, little information is available about the gene transfer efficiency in human malignant glioma in vivo. We compared the feasibility and safety of retrovirus- and adenovirus-mediated beta-galactosidase gene transfer in human malignant glioma. Beta-galactosidase gene was transferred to 10 patients with malignant glioma via a catheter inserted into the tumor. The catheter was left in place until the tumor resection. To maximize gene transfer efficiency, gene transfer vectors (BAG retroviruses, titer, 6 x 10(5) CFU; and adenoviruses, titer from 3 x 10(8) to 3 x 10(10) PFU) were injected into the tumor via the catheter once a day for three consecutive days, followed by tumor resection 1-2 days later. Tumor was resected in such a way that the catheter was still in place inside the tumor, which permitted accurate histological analysis of the transduced tumors. X-Gal staining for beta-galactosidase activity was used to study gene transfer efficiency and distribution of the marker gene. Beta-galactosidase gene transfer was well tolerated with both vectors. Except for two patients with clear increases in serum adenovirus antibody titers, no adverse tissue responses or systemic complications were noticed in any of the patients. Gene transfer was successful in all patients. Gene transfer efficiency varied between <0.01 and 4% with retroviruses and between <0.01 and 11% with adenoviruses. However, the transgene activity was not evenly distributed in the tumors. Both glioma cells and endothelium in the tumor blood vessels were transduced with retro- and adenovirus vectors. In conclusion, the safety and feasibility of in vivo gene transfer to human malignant glioma was established with retro- and adenovirus vectors. Adenoviruses were more efficient than retroviruses in achieving in vivo gene transfer. Transduction of endothelial cells may have important consequences for the proposed treatment strategies and selection of treatment genes. The results justify clinical gene therapy trials for malignant glioma.
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PMID:Beta-galactosidase gene transfer to human malignant glioma in vivo using replication-deficient retroviruses and adenoviruses. 972 Oct 87

Early bone marrow infection of Moloney murine leukemia virus (M-MuLV)-infected mice was studied. Previous experiments indicated that early bone marrow infection is essential for the efficient development of T lymphoma. In order to identify the cellular pathway of infection in the bone marrow, infection of mice with a helper-free replication-defective M-MuLV-based retroviral vector was carried out. Such a vector will undergo only one round of infection, without spreading to other cells; thus, cells infected by the initially injected virus (directly infected cells) can be identified. For these experiments, the BAG vector that expresses bacterial beta-galactosidase was employed. Neonatal NIH/Swiss mice were inoculated intraperitoneally with ca. 10(6) infectious units of a BAG vector pseudotyped with M-MuLV proteins, and bone marrow cells were recovered 2 to 12 days postinfection. Single-cell suspensions were tested for infection by staining with X-Gal (5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside) or by immunofluorescence with an anti-beta-galactosidase antibody. Two sizes of infected cells were evident: large multinucleated cells and small nondescript (presumptively hematopoietic) cells. Secondary stains for lineage-specific markers indicated that the large cells were osteoclasts. Some of the small cells expressed nonspecific esterase, which placed them in the myeloid lineage, but they lacked markers for hematopoietic progenitors (mac-1, gr-1, sca-1, and CD34). These results provide evidence for primary M-MuLV infection of osteoclasts or osteoclast progenitors in the bone marrow, and they suggest that known hematopoietic progenitors are not primary targets for infection. However, the subsequent spread of infection to hematopoietic progenitors was indicated, since bone marrow from mice infected in parallel with replication-competent wild-type M-MuLV showed detectable infection in small cells positive for mac-1 or CD34, as well as in osteoclasts.
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PMID:Identification of directly infected cells in the bone marrow of neonatal moloney murine leukemia virus-infected mice by use of a moloney murine leukemia virus-based vector. 988 68

The effect of steroids on adipogenesis by D1-BAG, a pluripotent cell cloned from mouse bone marrow and transfected with traceable genes encoding beta-galactosidase and neomycin resistance, was investigated in vitro in culture and in vivo after injection into mice. Treatment of D1-BAG cells in culture with dexamethasone produced an accumulation of lipid vesicles and stimulated expression of the fat cell-specific 422(aP2) mRNA. Fifty-six mice each received 1 x 10(6) D1-BAG cells, either by tail-vein injection or by direct injection into the marrow of the right femur. Another 38 mice received either saline injection or no treatment as controls. Half of the animals in each group were treated with 3 mg/kg of methylprednisolone per week. Analysis of marrow blow-outs by flow cytometry, DNA analysis by PCR, and X-gal stain of histological sections indicated that cells transplanted by either intravenous or intramedullary injection had appeared and persisted in the marrow of host mice. Cell sorting by flow cytometry and staining with Sudan IV demonstrated that steroid treatment produced adipogenesis in 5-9% of transplanted cells. The results indicate that steroid-induced differentiation of potentially osteogenic marrow cells into adipocytes in vivo may contribute to the development of osteoporosis and osteonecrosis.
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PMID:Pluripotential marrow cells produce adipocytes when transplanted into steroid-treated mice. 1082 8


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