TARGETED GENE THERAPY
Subject:Sickle Cell (The following material is presented in Ascending Date Order)
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Researcher Name shown is my estimate of Principal Researcher
DB Key:1996-SC-A Doc:Abstract Vector:RDO RNA-DNA chimeric oligonucleotide Experiment:Failed or Not Applicable Of Note:As few as 10% normal hematopoietic cells
9/1/1996-----Kmiec EB-----Thomas Jefferson University Title:Correction of the mutation responsible for sickle cell anemia by an RNA-DNA oligonucleotide Link:http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=8703073&form=6&db=m&Dopt=r Disease Information:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10791557&dopt=Abstract
Snippet: A chimeric oligonucleotide composed of DNA and modified RNA residues was used to direct correction of the mutation in the hemoglobin betaS allele. After introduction of the chimeric molecule into lymphoblastoid cells homozygous for the betaS mutation, there was a detectable level of gene conversion of the mutant allele to the normal sequence. The efficient and specific conversion directed by chimeric molecules may hold promise as a therapeutic method for the treatment of genetic diseases
DB Key:1997-SC-A Doc:Abstract Vector:RDO RNA-DNA chimeric oligonucleotide Experiment:Failed or Not Applicable Of Note:5-11% conversion rate was measured
11/1/1997-----Kmiec EB-----Thomas Jefferson University Title:Targeted gene conversion in a mammalian CD34+-enriched cell population using a chimeric RNA/DNA oligonucleotide Link:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9428613&dopt=Abstract Disease Information:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10791557&dopt=Abstract
Snippet: Gene conversion of genetically inherited point mutations is a fundamental methodology for treating a variety of diseases. We tested the feasibility of a new approach using an RNA/DNA chimeric oligonucleotide. The beta-globin gene was targeted at the point mutation causing sickle cell anemia. The chimera is designed to convert an A residue to a T after creating a mismatched basepair. In a CD34+-enriched population of normal cells a 5-11% conversion rate was measured using restriction enzyme polymorphism and direct DNA sequence analyses. The closely related delta-globin gene sequence appeared unchanged despite successful conversion at the beta-globin locus. Gene conversion of genetically inherited point mutations is a fundamental methodology for treating a variety of diseases. We tested the feasibility of a new approach using an RNA/DNA chimeric oligonucleotide. The beta-globin gene was targeted at the point mutation causing sickle cell anemia. The chimera is designed to convert an A residue to a T after creating a mismatched basepair. In a CD34+-enriched population of normal cells a 5-11% conversion rate was measured using restriction enzyme polymorphism and direct DNA sequence analyses. The closely related delta-globin gene sequence appeared unchanged despite successful conversion at the beta-globin locus.
DB Key:1999-SC-A Doc:Abstract Vector:NA Not Applicable Experiment:Failed or Not Applicable Of Note:The yeast system produces a recombinant sickle Hb that is identical by about a dozen biochemical and physiological criteria with the natural sickle Hb purified from the red cells of sickle-cell anaemia patients. Most importantly, the gelling concentration of this recombinant sickle Hb is the same as that of the HbS purified from human sickle red cells.
4/1/1999-----Li,Xianfeng-----Northeastern University Title:Mutational analysis of sickle haemoglobin (Hb) gelation Link:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10075913&dopt=Abstract 2nd Link:http://bab.portlandpress.com/bab/029/bab0290165.htm Disease Information:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10791557&dopt=Abstract
Snippet: We have recently reported the expression of human sickle Hb (HbS) in the yeast Saccharomyces cerevisiae that carries a plasmid containing the human - and b-globin cDNA sequences; N-terminal nascent protein processing is correct and a soluble correctly folded Hb tetramer is produced. The yeast system produces a recombinant sickle Hb that is identical by about a dozen biochemical and physiological criteria with the natural sickle Hb purified from the red cells of sickle-cell anaemia patients. Most importantly, the gelling concentration of this recombinant sickle Hb is the same as that of the HbS purified from human sickle red cells. The misfolding of Hb reported for the Escherichia coli-expressed protein is not apparent for Hb expressed in yeast by any of the criteria that we have used for characterization
DB Key:1999-SC-B Doc:American Scientist Vector:RDO RNA-DNA chimeric oligonucleotide Experiment:Failed or Not Applicable Of Note:For example, sickle cell anemia is the result of a single nucleotide substitution, a single letter misspelled, in the gene encoding the b-globin strand of hemoglobin
5/1/1999-----Kmiec EB-----Thomas Jefferson University Title:Targeted Gene Repair Link:http://www.americanscientist.org/articles/99articles/kmiecrepair.html
Snippet: Our work builds on earlier studies from Fred Sherman’s laboratory at the University of Rochester, who used a similar technique to change a single nucleotide. But the oligomers used by the Sherman group were unstable, and the team never extended its work. It turns out that mammalian cells contain enzymes that either degrade the ends of DNA molecules, or link them in long arrays called concatamers, which essentially destroys the integrity of the oligomers. We discovered that we could increase the stability of an oligomer by attaching segments of RNA to each of its ends. Like DNA, RNA is also composed of strings of nucleotides and therefore can bind to DNA in the same complementary manner as can another strand of DNA. (RNA contains no thymine. Instead, the uracil in RNA pairs with the adenine in DNA.)
DB Key:2000-SC-A Doc:Abstract Vector:TFO Triple helix-forming oligonucleotide Experiment:Failed or Not Applicable Of Note:We have explored the possibility of activating the gamma-globin gene expression by triplex-forming oligonucleotide (TFO)-directed targeted mutagenesis.
1/1/2000-----Glazer PM-----University of South Alabama College of Medicine Title:Activation of human gamma-globin gene expression via triplex-forming oligonucleotide (TFO)-directed mutations in the gamma-globin gene 5' flanking region Link:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10721715&dopt=Abstract Disease Information:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10791557&dopt=Abstract
Snippet: Human beta-globin disorders, such as sickle cell anemia and beta-thalassemia, are relatively common genetic diseases cause by mutations in the beta-globin gene. Increasing gamma-globin gene expression has been found to greatly reduce the disease symptom. However, the gamma-globin gene is developmentally regulated and normally expressed at high levels only during the fetal stage of human development. We have explored the possibility of activating the gamma-globin gene expression by triplex-forming oligonucleotide (TFO)-directed targeted mutagenesis. Using a psoralen-conjugated TFO designed to bind to a site overlapping with an Oct-1 binding site at the -280 region of the gamma-globin gene, targeted mutagenesis of the Oct-1 binding site has been achieved by transfecting the in-vitro-formed plasmid-oligo complex into human normal fibroblast (NF) cells. The mutation frequency at the target site was estimated to be 20% by direct DNA sequencing analysis. In-vitro protein binding assays indicated that these mutations reduced Oct-1 binding to the target site. In-vivo gene expression assays demonstrated activation of gamma-globin gene expression from these mutations in mouse erythroleukemia (MEL) cells. The levels of the gamma-globin gene expression increased by as much as fourfold in mutants with single base changes. These results suggest that the -280 region of the Agamma-globin gene negatively regulates the gamma-globin gene expression, and mutations at the Oct-1 binding site can lead to activation of the gamma-globin gene and generate the hereditary persistence of fetal hemoglobin (HPFH) condition. This study may provide a novel approach for gene therapy of sickle cell disease. The data may also have implications in gene therapy for other diseases including genetic diseases and cancers by introduc
DB Key:2001-SC-A Doc:Abstract Vector:RDO RNA-DNA chimeric oligonucleotide Experiment:Failed or Not Applicable Of Note:Saccharomyces Cerevisae
5/1/2001-----Kmiec EB-----University of Delaware Title:In vitro and in vivo nucleotide exchange directed by chimeric RNA/DNA oligonucleotides in Saccharomyces cerevisae Link:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11401693&dopt=Abstract
Snippet: To this end, we have identified genes that control targeted repair, using the genetically tractable organism, Saccharomyces cerevisae and a bank of yeast mutants
DB Key:2002-SC-A Doc:Abstract Vector:RDO RNA-DNA chimeric oligonucleotide Experiment:Failed or Not Applicable Of Note:Human Cell Success
1/1/2002-----Kmiec EB-----University of Texas Medical Branch Title:Targeted beta-globin gene conversion in human hematopoietic CD34(+ )and Lin(-)CD38(-)cells. Link:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11857070&dopt=Abstract Disease Information:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10791557&dopt=Abstract
Snippet: Chimeric oligonucleotides have been used successfully to correct point and frameshift mutations in several cell types, as well as in animal and plant models. However, their application to primitive human blood cells has been limited. In this investigation, chimeric oligonucleotides designed to direct a site-specific nucleotide exchange in the human beta-globin gene (an A to T substitution within codon 6) were introduced into normal human CD34(+) and Lin(-)CD38(-) cells via microinjection. This A to T nucleotide exchange introduces the single site mutation responsible for sickle cell anemia. In 23% of experimental samples, gene conversion was detected in the progeny of microinjected CD34(+) and Lin(-)CD38(-) cells that were cultured for at least 4 weeks. In addition, gene conversion was detected in the erythroid progeny of Lin(-)CD38(-) cells at the mRNA level. Conversion rates as high as 10-15% in 11% (five of 44) of experimental samples were confirmed by allele-specific PCR and sequence analysis of genomic DNA from the progeny of microinjected Lin(-)CD38(-) cells. Given that as few as 10% normal hematopoietic cells are sufficient to keep patients free of sickle cell disease, the level of conversion we have achieved in some samples may well be of therapeutic benefit in patients with sickle cell disease.
DB Key:2002-SFHR-B6 Doc:Abstract Vector:SFHR Small Fragment DNA Experiment:Failed or Not Applicable Of Note:The potential for one gene targeting technique, small fragment homologous replacement (SFHR) to the gene therapy treatment of sickle cell disease (SCD) is presented
6/1/2002-----Goncz KK-----University of Vermont Title:Application of SFHR to gene therapy of monogenic disorders Link:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12032689&dopt=Abstract Disease Information:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10791557&dopt=Abstract
Snippet: The potential for one gene targeting technique, small fragment homologous replacement (SFHR) to the gene therapy treatment of sickle cell disease (SCD) is presented
DB Key:2002-SC-M Doc:Abstract Vector:RDO RNA-DNA chimeric oligonucleotide Experiment:Successful Of Note:Saccharomyces cerevisae
7/1/2002-----Kmiec EB-----University of Delaware Title:Rad51p and Rad54p, but not Rad52p, elevate gene repair in Saccharomyces cerevisiae directed by modified single-stranded oligonucleotide vectors Link:http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12087156&dopt=Abstract 2nd Link:http://nar.oupjournals.org/cgi/content/abstract/30/13/2742?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&author1=Kmiec+EB&searchid=1032104998174_674&stored_search=&FIRSTINDEX=0&sortspec=Score+desc+PUBDATE_SORTDATE+desc&journalcode=nar
Snippet: In sharp contrast, RAD52 gene expression serves to reduce gene repair activity in rescue experiments and in experiments where RAD52 is overexpressed in a wild-type strain
DB Key:2002-SC-N Doc:Biography Vector:RDO RNA-DNA chimeric oligonucleotide Experiment:Failed or Not Applicable Of Note:Saccharomyces cerevisae
7/1/2002-----Rothstein,Rodney-----Columbia University Title:Biography Link:http://icg.cpmc.columbia.edu/faculty_Rothstein.htm |