Generating a transgenic mouse line stably expressing human MHC surface antigen from a HAC carrying multiple genomic BACs.
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ABSTRACT:
SUBMITTER: Hasegawa Y
PROVIDER: S-EPMC4339693 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:AIM:The human cytochrome P-450 2C18(CYP2C18) has been characterized. However, the protein has not been purified from liver and very little is known regarding the specific substrate of CYP2C18. In order to study its enzymatic activity for drug metabolism, the CYP2C18 cDNA was cloned and a stable CHL cell line expressing recombinant CYP2C18 was established. METHODS:The human CYP2C18 cDNA was amplified with reverse transcription-polymerase chain reaction (RT-PCR) from total RNAs extracted from human liver and cloned into pGEM-T vector. The cDNA segment was identified by DNA sequencing and subcloned into a mammalian expression vector pREP9. A transgenic cell line was established by transfecting the recombinant plasmid of pREP9-CYP2C18 to Chinese hamster lung (CHL) cell. The enzyme activity of CYP2C18 catalyzing oxidation of tolbutamide to hydroxytolbutamide in postmitochondrial supernant(S9) fraction of the cell was determined by high performance liquid chromatography(HPLC). RESULTS:The amino acid sequence predicted from the cloned cDNA segment was identical to that of reported by Romkes et al (GenBank accession number: M61856, J05326). The S9 fraction of the established cell line metabolizes tolbutamide to hydroxytolbutamide. Tolbutamide hydroxylase activity was found to be 0.509+/-0.052 micromol x min(-1) x g(-1) S9 protein or 8.82+/-0.90 mol x min(-1) x mol(-1) CYP, but was undetectable in parental CHL cell. In addition, we have identified a CYP2C18 cDNA clone with exon 5 missing. CONCLUSION:The cDNA of human CYP2C18 was successfully cloned and a cell line, CHL-CYP2C18, efficiently expressing the protein of CYP2C18, was established. A spliced variant of CYP2C18 with exon 5 missing was identified in the cloning process.
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Project description:Adoptive transfer of T cells expressing a CD19-specific chimeric antigen receptor (CAR) is being evaluated in multiple clinical trials. Our current approach to adoptive immunotherapy is based on a second generation CAR (designated CD19RCD28) that signals through a CD28 and CD3-? endodomain. T cells are electroporated with DNA plasmids from the Sleeping Beauty (SB) transposon/transposase system to express this CAR. Stable integrants of genetically modified T cells can then be retrieved when co-cultured with designer artificial antigen presenting cells (aAPC) in the presence of interleukin (IL)-2 and 21. Here, we reveal how the platform technologies of SB-mediated transposition and CAR-dependent propagation on aAPC were adapted for human application. Indeed, we have initiated clinical trials in patients with high-risk B-lineage malignancies undergoing autologous and allogeneic hematopoietic stem-cell transplantation (HSCT). We describe the process to manufacture clinical grade CD19-specific T cells derived from healthy donors. Three validation runs were completed in compliance with current good manufacturing practice for Phase I/II trials demonstrating that by 28 days of co-culture on ?-irradiated aAPC ?10(10) T cells were produced of which >95% expressed CAR. These genetically modified and propagated T cells met all quality control testing and release criteria in support of infusion.
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