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

---

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

Cationic liposomes have been proposed as alternative to adenovirus in the treatment of cystic fibrosis lung disease. Therefore, we have investigated the efficiency of two lipid mixtures in mediating gene transfer in in vitro and in vivo models. The cationic lipid DOTMA (N-(1-(2,3(dioleyloxy)propyl)-n,n,n-trimethylammoniumchloride++ +) and DOGS (dioctadecylamidoglycylspermine) were used in combination with the neutral lipid DOPE (dioleoylphosphatidylethanolamine). The relative transfection efficiencies of the two cationic liposomes were tested using the bacterial beta-galactosidase (lacZ) and the firefly luciferase genes. Gene expression was detected in both cell limes and primary culture of rhesus monkey airway epithelium after transfection with plasmid DNA complexed with DOGS/DOPE or DOTMA/DOPE. Transfection efficiency of both types of lipids was higher in the mouse fibroblast 3T3 cell line as compared to human carcinoma A549 cells and primary epithelial cultures. Administration of DNA-liposome complexes via intratracheal instillation resulted in expression of the lacZ and luciferase marker gene in the mouse airways. In vivo transfection mediated by both types of liposomes were proven to be far less efficient than adenovirus treatment.
...
PMID:In vitro and in vivo gene transfer to pulmonary cells mediated by cationic liposomes. 861 25

A rapid, quantitative, in vivo assay of cytotoxic responses would facilitate experimental evaluation of the potency of novel vaccine strategies. We have developed an in vivo cytotoxicity assay in which target cells expressing a luciferase reporter gene are implanted as monolayers on polystyrene disks onto the muscle tissue of mice. The luciferase activity retrievable from the adjacent tissue is used as an index of cytotoxicity. Implantation of B16 or NIH/3T3 cells expression the beta-galactosidase gene indicated that the target cells migrated to the muscle tissue from plastic within 4 h and then remained localized in the area of the disk. The amounts of luciferase retrievable from the adjacent tissue a few days post implantation readily detected the immune response induced by allo-immunization of fibroblasts or by production of interleukin-4 by tumor cells co-mixed with implanted reporter cells. Histologic analysis showed a correlation between the amount of luciferase retrieved and the number of viable target cells at the implantation site. Recruitment of immune effector cells which may be responsible for target cell death and luciferase elimination could be readily visualized. This simple cytotoxicity assay can be used as an in vivo assay of the net effect of cytotoxic immune responses.
...
PMID:In vivo cytotoxicity assay for assessing immunity. 861 69

Replication-deficient adenoviruses have been used to transfer various genes of interest to mammalian tissues in vivo. Effective gene therapy for inborn genetic defects presenting with significant morbidity and mortality at birth will require correction of the defect prenatally. To test the hypothesis that intra-amniotically administered adenovirus transfers gene expression to fetal tissues, replication-deficient human type 5 adenovirus carrying the lacZ gene which encodes nuclear-targeted bacterial beta-galactosidase (Av1LacZ4) was instilled into the amniotic cavity of fetal sheep (10(10) to 1.5 x 10(11) pfu) and fetal mice (10(9) pfu) at 0.8 term gestation. Amniotic membranes and gastrointestinal and respiratory tract tissues were harvested after 3 d, bacterial beta-galactosidase activity was determined by 5-bromo-4-chloro-3-indoyl-beta-D-galactopyranoside (X-gal) enzyme-histochemistry, and tissue integrity was assessed in sections stained with hematoxylin and eosin. Bacterial beta-galactosidase activity was abundant in amniotic membranes and present in lower levels in esophagus, stomach, and small intestine as well as in conducting airways and pulmonary alveoli. To determine whether gene transfer by intraamniotic injection of adenovirus was dose-dependent, Av1Luc1, an adenoviral vector carrying the gene for luciferase (10(5)-10(9) pfu), was injected intraamniotically into fetal mice at 0.8 term gestation. Luciferase activity measured after 3 d in tissue homogenates of Av1Luc1-treated fetal mice revealed a linear dose response in amniotic membranes and gastrointestinal and respiratory tract organs. Intraamniotic administration of an adenoviral gene vector leads to expression of the transferred gene in amniotic membranes as well as in fetal gastrointestinal and respiratory tract tissues in a dose-dependent manner.
...
PMID:Intraamniotic administration of an adenoviral vector for gene transfer to fetal sheep and mouse tissues. 861 83

Mechanisms by which the plus-sense RNA genomes of picornaviruses are replicated remain poorly defined, but existing models do not suggest a role for sequences encoding the capsid proteins. However, candidate RNA replicons (delta P1 beta gal and delta P1Luc), representing the sequence of human rhinovirus 14 virus (HRV-14) with reporter protein sequences (beta-galactosidase or luciferase, respectively) replacing most of the P1 capsid-coding region, failed to replicate in transfected H1-HeLa cells despite efficient primary cleavage of the polyprotein. To determine which P1 sequences might be required for RNA replication, HRV-14 mutants in which segments of the P1 region were removed to frame from the genome were constructed. Mutants with deletions involving the 5'proximal 1,489 nucleotides of the P1 region replicated efficiently, while those with deletions involving the 3' 1,079 nucleotides did not. Reintroduction of the 3' P1 sequence into the nonreplicating delta P1Luc construct resulted in a new candidate replicon, delta P1Luc/VP3, which replicated well and expressed luciferase efficiently. Capsid proteins provided in trans by helper virus failed to rescue the nonreplicating delta P1Luc genome but were able to package the larger-than-genome-length delta P1Luc/VP3 replicon. Thus, a 3'-distal P1 capsid-coding sequence has a previously unrecognized cis-active function related to replication of HRV-14 RNA.
...
PMID:Capsid coding sequence is required for efficient replication of human rhinovirus 14 RNA. 862 20

Degradable matrices containing expression plasmid DNA [gene-activated matrices (GAMs)] were implanted into segmental gaps created in the adult rat femur. Implantation of GAMs containing beta-galactosidase or luciferase plasmids led to DNA uptake and functional enzyme expression by repair cells (granulation tissue) growing into the gap. Implantation of a GAM containing either a bone morphogenetic protein-4 plasmid or a plasmid coding for a fragment of parathyroid hormone (amino acids 1-34) resulted in a biological response of new bone filling the gap. Finally, implantation of a two-plasmid GAM encoding bone morphogenetic protein-4 and the parathyroid hormone fragment, which act synergistically in vitro, caused new bone to form faster than with either factor alone. These studies demonstrate for the first time that repair cells (fibroblasts) in bone can be genetically manipulated in vivo. While serving as a useful tool to study the biology of repair fibroblasts and the wound healing response, the GAM technology may also have wide therapeutic utility.
...
PMID:Stimulation of new bone formation by direct transfer of osteogenic plasmid genes. 865 Jan 65

The E2A protein is a mammalian transcription factor of the helix-loop-helix family which is implicated in cell-specific gene expression in several cell lineages. Mouse E2A contains two independent transcription activation domains, ADI and ADII; whereas ADI functions effectively in a variety of cultured cell lines, ADII shows preferential activity in pancreatic beta cells. To analyze this preferential activity in an in vivo setting, we adapted a system involving transient gene expression in microinjected zebra fish embryos. Fertilized one- to four-cell embryos were coinjected with an expression plasmid and a reporter plasmid. The expression plasmids used encode the yeast Gal4 DNA-binding domain (DBD) alone, or Gal4 DBD fused to ADI, ADII, or VP16. The reporter plasmid includes the luciferase gene linked to a promoter containing repeats of UASg, the Gal4-binding site. Embryo extracts prepared 24 h after injection showed significant luciferase activity in response to each of the three activation domains. To determine the cell types in which the activation domains were functioning, a reporter plasmid encoding beta-galactosidase and then in situ staining of whole embryos were used. Expression of ADI led to activation in all major groups of cell types of the embryo (skin, sclerotome, myotome, notochord, and nervous system). On the other hand, ADII led to negligible expression in the sclerotome, notochord, and nervous system and much more frequent expression in the myotome. Parallel experiments conducted with transfected mammalian cells have confirmed that ADII shows significant activity in myoblast cells but little or no activity in neuronal precursor cells, consistent with our observations in zebra fish. This transient-expression approach permits rapid in vivo analysis of the properties of transcription activation domains: the data show that ADII functions preferentially in cells of muscle lineage, consistent with the notion that certain activation domains contribute to selective gene activation in vivo.
...
PMID:An activation domain of the helix-loop-helix transcription factor E2A shows cell type preference in vivo in microinjected zebra fish embryos. 865 47

Nonviral, plasmid-based gene transfer into somatic tissues offers the prospect of various simple and safe therapeutic possibilities as well as applications in fundamental research. Although cationic lipids display efficient transfection activities in many in vitro systems, only low success rates using these vectors in vivo have been reported. We succeeded in defining conditions providing high levels of in vivo transfection in the brains of newborn mice. Our hypothesis was that conditions favorable for in vitro transfection (highly positively charged particles) were unlikely to be appropriate for in vivo conditions. When using the cationic lipid dioctadecylamido glycylspermine (Transfectam, DOGS) with a cytomegalovirus (CMV)-luciferase reporter gene, the best levels of transfection were obtained when using a low ratio of positive charges (supplied by the DOGS) to negative charges (carried by the DNA). Moreover, addition of the neutral lipid dioleoylphosphatidyl ethanolamine (DOPE) significantly enhanced transfection. Expression of the transgene diminished over time, independently of lipopolysaccharide content of the plasmid preparation used. This suggests that either a mitotic population of cells was preferentially transfected, or that promoter silencing was occurring. Histological examination of the spatial distribution of a beta-galactosidase-expressing transgene showed numerous groups of transfected cells both within the striatal parenchyma and in the paraventricular area. Thus, DNA-lipid complexes bearing overall charges close to neutrality open promising possibilities for modulating gene expression in the developing central nervous system and for therapy in the brain.
...
PMID:Lipospermine-based gene transfer into the newborn mouse brain is optimized by a low lipospermine/DNA charge ratio. 866 76

To utilize gene therapy, we required an efficient method to transfect intact islets before their use in transplantation. The biolistic method transforms cells by bombarding them with microprojectiles coated with DNA. Once internalized, the DNA is solubilized and expressed. We used the firefly luciferase gene driven by the human cytomegalovirus immediate early promoter as a reporter construct in freshly isolated BALB/c mouse islets to compare the transfection efficiency using either the biolistic method, lipofection, or recombinant adenoviral infection (n=4 in each case). The biolistic method achieved, on average, a 35-fold higher level of luciferase activity than the lipofection method (mean +/- SEM: 42.6 +/- 14.2 vs. 1.1 +/- 0.2 relative light units (RLU)/islet). Adenoviral infection achieved, on average, a further 25-fold higher level of luciferase activity than the biolistic method (1136.0 +/- 542.0 RLU/islet). The average proportion of islets recovered 48 hr after the biolistic blast was 53% (n=20). The average number of dissociated cells found to express the foreign gene product using beta-galactosidase as a reporter construct was 3% (n=6). Furthermore, nontransformed and biolistically transformed islets responded similarly to an in vitro glucose challenge (stimulation index of insulin release at 20.0 mM glucose/insulin release at 2.8 mM glucose = 2.8 and 3.0, respectively, P=0.9). Syngeneic, biolistically transfected islets functioned to reverse the diabetic state when transplanted (500 islets) beneath the renal capsule of alloxan-induced diabetic BALB/c recipients (n=7). This methodology can achieve efficient transfection of pancreatic islets while preserving their function and thus holds promise for ex vivo gene therapy of isolated islets prior to transplantation.
...
PMID:Successful biolistic transformation of mouse pancreatic islets while preserving cellular function. 866 98

Primary human fibroblasts and a series of cell lines (A549, BNL CL.2, H225, NIH 3T3 and Rat-1) are efficiently transfected by using positively charged complexes of plasmid DNA and transferrin-polylysine or polylysine in the presence of glycerol (1 molar to 1.8 molar, depending on the cell type). An increase in gene expression of up to several-hundredfold (compared to complexes without glycerol) is obtained if the transfection mixture is incubated with the cells for 3-4 h at 37 degrees C. This simple method has been used for transient expression of luciferase, beta-galactosidase and interleukin-2, and also for the generation of stably transfected cells.
...
PMID:Glycerol enhancement of ligand-polylysine/DNA transfection. 872 40

Cytokines can stimulate immune effector cells present within the oral mucosa and epidermis to respond to vaccination or to combat cancer. However, intravenous cytokine delivery is often inefficient and frequently accompanied by systemic toxicity. The goal of this study was to evaluate dogs as a large animal model for gene therapy of cancer because they develop spontaneous oral and epidermal tumors. In this report, we demonstrate that particle-mediated gene transfer of beta-galactosidase, luciferase, interleukin-2, interleukin-6, and granulocyte-macrophage colony stimulating factor (GM-CSF) complementary DNA (cDNA) into the oral mucosa and epidermis of healthy dogs resulted in effective, localized, transgenic protein expression. Additionally, the epidermal sites transfected with GM-CSF developed a profound inflammatory reaction characterized by neutrophilic infiltration. Clinical pathology analyses were unremarkable. These results demonstrate that in vivo particle-mediated gene transfer of canine oral mucosa and epidermis with cytokine cDNA can result in production of biologically active transgenic cytokines with minimal toxicity. These findings have applications to cancer immunotherapy using a gene gun approach.
...
PMID:In vivo particle-mediated cytokine gene transfer into canine oral mucosa and epidermis. 872 83


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---