Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Hypocalcemic vitamin D analogs are appealing molecules to exploit the immunomodulatory actions of active vitamin D in vivo. The functional modulation of dendritic cells is regarded as the key mechanism underlying their ability to regulate T cell responses. In contrast, the direct actions of vitamin D and structural analogs on T lymphocytes remain less well characterized. Microarray analysis was performed to gain insight into the direct immunomodulatory actions of TX527, a hypocalcemic vitamin D analog, on human T lymphocytes. Gene expression analysis revealed that TX527 regulated a wide variety of genes involved in different aspects of T cell function, including cellular growth and proliferation, cell death, cellular development, cellular movement and cell-to-cell signalling and interaction. Human CD3+ T cells, isolated from peripheral blood from healthy donors, were activated by anti-CD3/anti-CD28 and cultured in the presence of TX527 (10-8M) or vehicle (ethanol) for 10 days. Expression profiles of TX527-treated and vehicle-treated T cells were compared using Affymetrix Human Genome U133 Plus 2.0 Arrays.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression. Two-condition experiment, Normoxic MSCs vs. Hypoxic MSCs.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs. Two-condition experiment, KP MSCs vs. 3A6 MSCs.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Hypocalcemic vitamin D analogs are appealing molecules to exploit the immunomodulatory actions of active vitamin D in vivo. The functional modulation of dendritic cells is regarded as the key mechanism underlying their ability to regulate T cell responses. In contrast, the direct actions of vitamin D and structural analogs on T lymphocytes remain less well characterized. Microarray analysis was performed to gain insight into the direct immunomodulatory actions of TX527, a hypocalcemic vitamin D analog, on human T lymphocytes. Gene expression analysis revealed that TX527 regulated a wide variety of genes involved in different aspects of T cell function, including cellular growth and proliferation, cell death, cellular development, cellular movement and cell-to-cell signalling and interaction.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.