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)

Retrovirus-mediated gene transfer was used to develop a method for introducing genes into primary cultures of adult rat hepatocytes. Subconfluent monolayers of hepatocytes, cultured in hormonally defined media on different matrix substrata, were infected with helper-free stocks of a replication-defective retrovirus that constitutively expresses high levels of beta-galactosidase. Retrovirus-mediated transduction was measured by two methods: (i) an in situ cytochemical stain that specifically detects the expression of viral expressed beta-galactosidase, and (ii) Southern blot analysis, which measures the relative copy number of integrated provirus. Maximal transduction efficiency of approximately equal to 25% was achieved when the cells were infected after 3 days in culture; matrix had little effect on transduction efficiency. Enzyme cytochemical (catalase and glucose 6-phosphatase) and peroxidase immunocytochemical (asialoglycoprotein and UDP-glucuronosyltransferase) analyses of the cultures indicated that greater than 95% of cells were hepatocytes. The demonstration of hepatocyte-specific organelles in cells expressing the viral-directed beta-galactosidase provided unambiguous evidence for the transduction of hepatocytes. These methods should be useful in the development of liver-directed somatic gene therapy and in the study of liver-specific gene regulation.
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PMID:Retrovirus-mediated transduction of adult hepatocytes. 283 28

The intragastric administration to male Wistar rats of T-2 toxin at 1-1.3 mg/kg body weight for 7 days caused a sharp decrease in the liver activity of lysosomal enzymes: beta-galactosidase, beta-N-acetylglucosaminidase, alpha-mannosidase, cathepsins A, B, C and D and in the activity of enzymes of the 1st phase of metabolism of xenobiotics--aniline hydroxylase and carboxylesterase, as well as in the cytochrome P-450 level. At the same time, the subacute toxic effect of T-2 toxin was manifested in a significant increase in the activity of epoxide hydrolase and an enzyme of the 2nd phase of metabolism of xenobiotics--UDP-glucuronosyltransferase. A possible mechanism of the observed enzymological changes is discussed.
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PMID:Biochemical changes in subacute mycotoxicosis induced by T-2 toxin in rats. 379 60

Injection of a recombinant adenovirus expressing human bilirubin-UGT1 (Ad-hBUGT1) (3 x 10(9) plaque-forming units (pfu) intravenously) in adult bilirubin-UDP-glucuronosyltransferase-1 (BUGT1)-deficient Gunn rats resulted in biliary excretion of bilirubin glucuronides and a 70% reduction of serum bilirubin levels. However, the effect was transient, and host humoral and cellular immune response prevented transgene expression after subsequent injections. To determine whether injection during the neonatal period would tolerize the host to the recombinant virus, we injected 1 x 10(8) pfu of Ad-hBUGT1 or Ad-LacZ (a recombinant adenovirus expressing Escherichia coli beta-galactosidase) into 1-3-day-old Gunn rats. Two subsequent injections (3 x 10(9) pfu) were given 56 and 112 days after the initial injection. Injection of Ad-BUGT1, but not Ad-LacZ, reduced serum bilirubin by 70-76% of the levels in untreated pups (9 +/- 1.3 mg/dl), followed by a gradual increase to 3.25 +/- 0.3 mg/dl in 56 days; similar or greater reductions occurred after the second and third injection. Serum neutralizing antibody titer and cytotoxic lymphocyte activity against adenovirus-infected hepatocytes were low or undetectable. Thus, tolerization by injection of the virus during the neonatal period permits long term gene therapy by repeated injection of the virus.
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PMID:Long term correction of bilirubin-UDP-glucuronosyltransferase deficiency in Gunn rats by administration of a recombinant adenovirus during the neonatal period. 890 Jan 23

Recombinant adenoviruses are highly efficient at transferring foreign genes in vivo. However, duration of gene expression is limited by the host antiviral immune response which precludes expression upon viral readministration. We tested the feasibility of prolonging gene expression by induction of central tolerance to adenoviral antigens in bilirubin-UDP-glucuronosyltransferase-1 (BUGT1)-deficient Gunn rats. Tolerance was induced by intraperitoneal injection of antilymphocyte serum, followed by intrathymic inoculation of one of the following: a recombinant adenovirus (Ad), adenovirus human UDP-glucuronosyltransferase (Ad-hBUGT1) carrying the hBUGT1 gene; a protein extract of the same virus; or viral infected hepatocytes. Controls received intrathymic injections of normal saline. After 12 d all groups were injected intravenously with 5 x 10(9) pfu of either Ad-hBUGT1 or adenovirus beta-galactosidase (Ad-LacZ) (expressing the Escherichia coli beta-galactosidase [LacZ] gene). In all three groups of tolerized rats, hBUGT1 was expressed in the liver after administration of Ad-hBUGT1, with glucuronidation of biliary bilirubin of above 95%. Serum bilirubin levels decreased from 7.2 to 1.8 mg/dl within 1 wk and remained low for 7 wk. Similar findings were observed following repeat injections given on days 45 and 112. In control rats serum bilirubin levels were reduced for only 4 wk, and viral readministration was ineffective. In all tolerized groups, but not in controls, there was a marked inhibition of appearance of neutralizing antibodies and cytotoxic lymphocytes against the recombinant adenovirus. Injection of wild type adenovirus-5 (Ad5) into the tolerized rats elicited a wild type-specific cytotoxic lymphocyte response. This is the first demonstration of Ad-directed long-term correction of an inherited metabolic disease following central tolerization with thymic antigen.
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PMID:Induction of central tolerance by intrathymic inoculation of adenoviral antigens into the host thymus permits long-term gene therapy in Gunn rats. 895 29