Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The liver is an attractive target tissue for gene therapy. Current approaches for hepatic gene delivery include retroviral and adenoviral vectors, liposome/DNA, and peptide/DNA complexes. This study describes a technique for direct injection of DNA into liver that led to significant gene expression. Gene expression was characterized in both rats and cats following injection of plasmid DNA encoding several different proteins. Luciferase activity was measured after injection of plasmid DNA encoding the luciferase gene (pCMVL), beta-galactosidase (beta-Gal) activity was evaluated in situ using plasmid DNA encoding Lac Z (pCMV beta), and serum concentration of secreted human alpha-1-antitrypsin was measured following injection of plasmid DNA encoding this protein (pRC/CMV-sHAT). Several variables, including injection technique, DNA dose, and DNA diluent, were investigated. Direct injection of pCMVL resulted in maximal luciferase expression at 24-48 hr. beta-Gal staining demonstrated that the majority of transfected hepatocytes were located near the injection site. Significant concentrations of human alpha-1-antitrypsin were detected in the serum of animals injected with pRC/CMV-sHAT. These findings demonstrate the general principle that direct injection of plasmid DNA into liver can lead to significant gene expression.
 ...
PMID:Gene expression following direct injection of DNA into liver. 771 Nov 40

From a review of past studies and the report of new studies from our laboratory, this article provides strong evidence to show that WB-F344 (WB) rat liver epithelial cells are stem-like precursor cells for hepatocytes. WB cells are structurally and phenotypically simple epithelial cells that were isolated from the liver of an adult male Fischer 344 rat, under conditions that excluded their origin from hepatocytes in vivo. WB cells express a phenotypic repertory that overlaps, but is distinct from, that of both hepatocytes and bile duct epithelial cells. The complex phenotype of WB cells is compatible with their being embryonic or undifferentiated variants of either hepatocytes or bile duct epithelial cells. When WB cells are tagged genetically with genes for bacterial beta-galactosidase and neomycin resistance (BAG2-WB), they and their progeny can be distinguished from parental WB cells and hepatocytes by the expression of these gene products. Progeny of BAG2-WB cells that were transplanted into the liver parenchyma of syngeneic rats integrated into hepatic plates and acquired the morphological and functional attributes of adjacent host hepatocytes; the progeny of BAG2-WB cells in the liver express albumin, tyrosine aminotransferase, alpha-1-antitrypsin, and transferrin. We also demonstrate that progeny of BAG2-WB cells can be recovered from livers into which they have been transplanted, which may allow the elucidation of alterations in gene expression that accompany their differentiation.
 ...
PMID:Isolation, culture, and transplantation of rat hepatocytic precursor (stem-like) cells. 823 70

Skeletal muscle is a privileged target for long-term rAAV-mediated gene transfer in mouse, rat, dog and non-human primates. Intramuscular injections of rAAV encoding human factor IX in hemophilia B patients have been initiated, based on promising results gathered in affected dogs. We found that intramuscular rAAV administration in rats resulted in restricted transduction essentially along the myofibers axis with poor lateral diffusion. This suggested that the transduction rate might be limited by the ability of the virus to reach sites distant from the injection point. We tested whether hyaluronidase, an enzyme which dissociates the extracellular matrix, could enhance vector diffusion when injected in the rat muscle before administration of rAAV encoding either nuclear-localized beta-galactosidase (rAAVCMVnlsLacZ) or the human alpha-1-antitrypsin (rAAVCMVhAAT) under the control of the cytomegalovirus immediate--early promoter (CMV). The results showed that pretreatment of the rat anterior tibialis muscle with hyaluronidase resulted in: (1) a larger diffusion of the virus indicated by an increase in the area containing LacZ-transduced fibers, and (2) a two- to three-fold increase of transduction efficiency measured by the number of LacZ-positive fibers or by the hAAT serum concentration. We also provide evidence that hyaluronidase was well tolerated and was not associated with short- or long-term toxicity evaluated by morphological studies. Finally, in our experimental conditions, hyaluronidase did not promote rAAV dissemination to other organs as assessed by PCR to detect vector sequences. We conclude that pretreatment of skeletal muscle by hyaluronidase, a clinically available reagent, was harmless and resulted in a consistent and significant increase in rAAV diffusion and transduction levels.
 ...
PMID:Hyaluronidase enhances recombinant adeno-associated virus (rAAV)-mediated gene transfer in the rat skeletal muscle. 1098 69

We have characterized the ability of adeno-associated virus (AAV) serotypes 1-9 in addition to nineteen novel vectors isolated from various tissues, to transduce mouse and human ciliated airway epithelium (HAE). Vectors expressing alpha-1-antitrypsin (AAT) and beta-galactosidase were co-instilled into the mouse lung. Of all the vectors tested rh.64R1, AAV5 and AAV6 were the most efficient. The high transduction observed in mouse was reproduced in HAE cell cultures for both rh.64R1 and AAV6 but not for AAV5. Since AAV6 was the most efficient vector in mouse and HAE we also tested the transduction efficiencies of the AAV6 singleton vectors (i.e., AAV6 variants with targeted mutations) in these models. Of these, AAV6.2 transduced mouse airway epithelium and HAE with greater efficiency than all other AAV vectors tested. We demonstrated that AAV6.2 exhibits improved transduction efficiency compared to previously reported AAVs in mouse airways and in culture models of human airway epithelium and that this vector requires further development for preclinical and clinical testing.
 ...
PMID:Transduction efficiencies of novel AAV vectors in mouse airway epithelium in vivo and human ciliated airway epithelium in vitro. 1906 97