Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The structural gene of Hepatitis B virus surface protein (HBsAg) was introduced into a plasmid capable of autonomous replication and selection in both the yeast Saccharomyces cerevisiae and E. coli. In this plasmid transcription of the HBsAg is initiated by the 5'-flanking sequence of the yeast 3-phosphoglycerate kinase (PGK) gene and terminated by the 3'-flanking region of the yeast TRP1 gene. Yeast cells containing this plasmid produce a new major species of mRNA of 1200 nucleotides in length coding for HBsAg. Viral surface antigen is made in nonglycosylated form at a level of about 1-2 percent of total yeast protein. A small fraction of this polypeptide (2-5 percent) is found in aggregated form upon yeast cell disruption by glass beads. This material is similar in size, density, and shape to the 22nm particle, isolated from the plasma of human hepatitis carriers, and induced comparable levels of HBsAg antibodies in mice when compared with the natural particle.
 ...
PMID:Expression of hepatitis B virus surface antigen in yeast. 634 21

We investigated the cell clonality of 12 cases of female solitary hepatocellular carcinoma (HCC) that were associated with hepatitis virus infection. The clonal origin of HCC could be assessed by the method based on restriction fragment length polymorphism (RFLP) of X-chromosome-linked androgen receptor gene (AR) and phosphoglycerate kinase (PGK) gene, taking advantage of random inactivation of one of two X-chromosomes by methylation in females. We extracted DNA samples from both fresh and paraffin-embedded specimens of the same lesion as a source of DNA sample for polymerase chain reaction (PCR). Consequently, it was possible to use methylation-sensitive restriction enzymes and PCR to study differential methylation patterns among alleles of these genes for both DNA samples. The RFLPs of AR gene and PGK gene were found in eight of 12 cases and five of 12 cases, respectively. There were two cases which had no RFLPs in either AR gene or PGK gene. All cases of HCC which had RFLP in either AR gene or PGK gene demonstrated monoclonal origin of the tumor regardless of their histologic patterns.
 ...
PMID:[Clonal analysis of hepatocellular carcinoma]. 867 65

Recent experiments point to the great value of lentiviral vectors for the transduction of human hematopoietic stem cells (hHSCs). Vectors used so far, however, have been poorly satisfying in terms of either biosafety or efficiency of transgene expression. Herein is described the results obtained with human immunodeficiency virus-based vectors optimized in both of these aspects. It is thus shown that vectors containing the EF1alpha and, to a lesser extent, the phosphoglycerate kinase (PGK) promoter, govern high-level gene expression in human hematopoietic progenitors as well as derived hematopoietic lineages of therapeutic relevance, such as erythrocytes, granulocytes, monocytes, dendritic cells, and megakaryocytes. EF1alpha promoter-containing lentiviral vectors can also induce strong transgene expression in primary T lymphocytes isolated from peripheral blood. A self-inactivating design did not affect the performance of EF1alpha promoter-based vectors but significantly reduced expression from the PGK promoter. This negative effect could nevertheless be largely rescued by inserting the post-transcriptional regulatory element of woodchuck hepatitis virus upstream of the vector 3' long terminal repeat. These results have important practical implications for the genetic treatment of lymphohematologic disorders as well as for the study of hematopoiesis via the lentivector-mediated modification of hHSCs.
 ...
PMID:High-level transgene expression in human hematopoietic progenitors and differentiated blood lineages after transduction with improved lentiviral vectors. 1107 33

We have developed optimized versions of a conditionally replicating human immunodeficiency virus type 1 (HIV-1)-based lentiviral vector for gene therapy of HIV-1 infection. These vectors target HIV-1 RNAs containing sequences of the envelope gene by expressing a 1-kb fragment of the HIV-1 Tat/Rev intron in the antisense orientation. Expression of the envelope antisense gene (envAS) was evaluated under the control of different internal promoters such as the human phosphoglycerate kinase (PGK) promoter, the human EF1-alpha promoter, and the U3 region of the SL3 murine leukemia virus. The U3-SL3 promoter transactivates transcription from the vector HIV-1 LTR and drives higher expression levels of envAS-containing RNAs than other promoters in T-cell lines. The effect of other vector structural features was also evaluated. We found that the central polypurine tract and central termination sequence (cPPT) produce a small increase in vector infectivity of 2-fold to 3-fold and results in a 10-fold higher inhibition of wild-type viral replication in challenge experiments. The woodchuck hepatitis posttranscriptional regulatory element (WPRE) does not increase the cytoplasmic levels of envAS mRNA in T-cell lines. We observed that SupT1 and primary CD4(+) T cells transduced with these vectors showed high inhibition of HIV-1 replication, suppression of syncitium formation, and increased cell viability when infected with several HIV-1 laboratory strains. Our results suggest that higher vector copy number and increased levels of envAS RNA expression contribute to block replication of divergent strains of HIV-1.
 ...
PMID:Enhanced inhibition of human immunodeficiency virus type 1 replication by novel lentiviral vectors expressing human immunodeficiency virus type 1 envelope antisense RNA. 1206 36

Nucleoside analogs used in antiviral therapies need to be phosphorylated to their tri-phospho counterparts in order to be active on their cellular target. Human phosphoglycerate kinase (hPGK) was recently reported to participate in the last step of phosphorylation of cytidine L-nucleotide derivatives [Krishnan PGE, Lam W, Dutschman GE, Grill SP, Cheng YC. Novel role of 3-phosphoglycerate kinase, a glycolytic enzyme, in the activation of L-nucleoside analogs, a new class of anticancer and antiviral agents. J Biol Chem 2003;278:36726-32]. In the present work, we extended the enzymatic study of human PGK specificity to purine and pyrimidine nucleotide derivatives in both D- and L-configuration. Human PGK demonstrated catalytic efficiencies in the 10(4)-10(5)M(-1)s(-1) range for purine ribo-, deoxyribo- and dideoxyribonucleotide derivatives, either in D- or L-configuration. In contrast, it was poorly active with natural pyrimidine D-nucleotides (less than 10(3)M(-1)s(-1)). Pyrimidine L-enantiomers, which are promising therapeutic analogs against B hepatitis, were 2-25 times better substrates than their D-counterparts. The broad specificity of substrate of human PGK suggests that this enzyme may be involved in the cellular activation of several antiviral nucleoside analogs including dideoxyinosine, acyclovir, L-2'-deoxycytosine and L-2'-deoxythymidine.
 ...
PMID:Broad specificity of human phosphoglycerate kinase for antiviral nucleoside analogs. 1545 Sep 40

Fanconi anemia (FA) is an inherited genetic disease characterized mainly by bone marrow failure and cancer predisposition. Although gene therapy may constitute a good therapeutic option for many patients with FA, none of the clinical trials so far developed has improved the clinical status of these patients. We have proposed strategies for the genetic correction of bone marrow grafts from patients with FA, using lentiviral vectors (LVs). Here we investigate the relevance of the expression of FANCA to confer a therapeutic effect in cells from patients with FA-A, the most frequent complementation group in FA. Our data show that relatively weak promoters such as the vav or phosphoglycerate kinase (PGK) promoter confer, per copy of FANCA, physiological levels of FANCA mRNA in lymphoblastoid cell lines, whereas the cytomegalovirus and, more significantly, spleen focus-forming virus (SFFV) promoters mediated the expression of supraphysiological levels of FANCA mRNA. Insertion of the woodchuck hepatitis virus posttranscriptional regulatory element (WPRE) or a mutated WPRE into the 3' region of PGK-FANCA LVs significantly increased FANCA mRNA levels. At the protein level, however, all tested vectors conferred, per copy of FANCA, similar and physiological levels of the protein, except SFFV LVs, which again conferred supraphysiological levels of FANCA. In spite of their different activity, all tested vectors mediated a similar phenotypic correction in FA-A lymphoblastoid cell lines and also in hematopoietic progenitors from patients with FA-A. On the basis of the efficacy and safety properties of PGK LVs, a PGK LV carrying FANCA and a mutant WPRE is proposed as an optimized vector for the gene therapy of patients with FA-A.
 ...
PMID:Development of lentiviral vectors with optimized transcriptional activity for the gene therapy of patients with Fanconi anemia. 2000 54

We previously compared the expression of several human factor VIII (fVIII) transgene variants and demonstrated the superior expression properties of B domain-deleted porcine fVIII. Subsequently, a hybrid human/porcine fVIII molecule (HP-fVIII) comprising 91% human amino-acid sequence was engineered to maintain the high-expression characteristics of porcine fVIII. The bioengineered construct then was used effectively to treat knockout mice with hemophilia A. In the current study, we focused on optimizing self-inactivating (SIN) lentiviral vector systems by analyzing the efficacy of various lentiviral components in terms of virus production, transduction efficiency and transgene expression. Specifically, three parameters were evaluated: (1) the woodchuck hepatitis post-transcriptional regulatory element (WPRE), (2) HIV versus SIV viral vector systems and (3) various internal promoters. The inclusion of a WPRE sequence had negligible effects on viral production and HP-fVIII expression. HIV and SIV vectors were compared and found to be similar with respect to transduction efficiency in both K562s and HEK-293T cells. However, there was an enhanced expression of HP-fVIII by the SIV system, which was evident in both K562 and BHK-M cell lines. To further compare expression of HP-fVIII from an SIV-based lentiviral system, we constructed expression vectors containing the high expression transgene and a human elongation factor-1 alpha, cytomegalovirus (CMV) or phosphoglycerate kinase promoter. Expression was significantly greater from the CMV promoter, which also yielded therapeutic levels of HP-fVIII in hemophilia A mice. Based on these studies, an optimized vector contains the HP-fVIII transgene driven by a CMV internal promoter within a SIV-based lentiviral backbone lacking a WPRE.
 ...
PMID:Generation of an optimized lentiviral vector encoding a high-expression factor VIII transgene for gene therapy of hemophilia A. 2299 97