Project description:Transcript profiling is crucial to study biological systems and various platforms have been implemented to survey mRNAs at the genome scale. We have assessed the characteristics of the CATMA microarray designed for Arabidopsis thaliana transcriptome analysis, and compared it with two commercial platforms from Agilent and Affymetrix. The CATMA array consists of gene-specific sequence tags of 150 to 500 base pairs, the Agilent (Arabidopsis 2) array of 60mer oligonucleotides, and the Affymetrix gene chip (ATH1) of 25mer oligonucleotide sets. We have matched each probe repertoire with the Arabidopsis genome annotation (TIGR release 5.0) and determined the correspondence between them. Array performance was analyzed by hybridization with labeled target derived from eight RNA samples made of shoot total RNA spiked with a calibrated series of 14 control transcripts. A total of fourteen cDNA clones were thus selected and used as templates to synthesize bona fide polyadenylated spike RNAs. Each spike RNA was calibrated then mixed in equal amount with one of the other spike RNAs to obtain seven pairs at equal concentration. These seven spike RNA pairs were then combined systematically to construct seven complex spike mixes in a design similar to an ordered Latin square, each mix containing six of the seven spike pairs in staggered concentrations covering five logs. To prevent loss of spike RNA through adsorption to the plastic ware, the spike mixes were prepared in 0.5 µg/µl Col RNA, resulting in a range of concentration from 0.1 to 10,000 copies per cellular equivalent (cpc), assuming that the total RNA contained 1% polyadenalated mRNA and that a cell contained on average 300,000 transcripts. These seven RNA samples included equal amounts of combined spike RNA . To convert the spike hybridization signals to ratios, an eighth sample was prepared, called the reference sample, consisting of the base Col RNA completed with all spike RNAs at a concentration of 100 cpc. The results from the eight experiments using the Affymetrix gene chips (ATH1) are available for analysis or download from this site.
Project description:Goal of this experiment is the identify differentially expressed genes in GBM zenografts that have been exposed to Cilengitide for 1 or 8 hours. A control with no cilengitide is also included. None of the tumors recieved radiation. Experiment Overall Design: 4 replicates of mice brains with tumor 103 are used as a control for expression with no cilengtide exposure. 4 replicates of mice brains with tumor 104 were exposed to cilengitide for 1 hour. 4 replicates of mice brains with tumor 105 were exposed to cilengitide for 8 hours.
Project description:We used microarrays to expression profile peripheral blood mononuclear cells (PBMCs) from LGL leukemia patients and control subjects to identify survival pathways that render leukemic LGL resistant to activation induced cell death. Experiment Overall Design: Leukemic PBMC RNA from 30 patients was extracted for target preparation and hybridization onto Affymetrix microarrays. We also isolated PBMCs and PBMCs subjected to enrichment for CD8+ cells from control patients. RNA from these cells (naïve or activated with phytohemagglutinin) was extracted for target preparation and hybridization onto Affymetrix microarrays.
Project description:Transcript profiling is crucial to study biological systems and various platforms have been implemented to survey mRNAs at the genome scale. We have assessed the characteristics of the CATMA microarray designed for Arabidopsis thaliana transcriptome analysis, and compared it with two commercial platforms from Agilent and Affymetrix. The CATMA array consists of gene-specific sequence tags of 150 to 500 base pairs, the Agilent (Arabidopsis 2) array of 60mer oligonucleotides, and the Affymetrix gene chip (ATH1) of 25mer oligonucleotide sets. We have matched each probe repertoire with the Arabidopsis genome annotation (TIGR release 5.0) and determined the correspondence between them. Array performance was analyzed by hybridization with labeled target derived from eight RNA samples made of shoot total RNA spiked with a calibrated series of 14 control transcripts. A total of fourteen cDNA clones were thus selected and used as templates to synthesize bona fide polyadenylated spike RNAs. Each spike RNA was calibrated then mixed in equal amount with one of the other spike RNAs to obtain seven pairs at equal concentration. These seven spike RNA pairs were then combined systematically to construct seven complex spike mixes in a design similar to an ordered Latin square, each mix containing six of the seven spike pairs in staggered concentrations covering five logs. To prevent loss of spike RNA through adsorption to the plastic ware, the spike mixes were prepared in 0.5 µg/µl Col RNA, resulting in a range of concentration from 0.1 to 10,000 copies per cellular equivalent (cpc), assuming that the total RNA contained 1% polyadenalated mRNA and that a cell contained on average 300,000 transcripts. These seven RNA samples included equal amounts of combined spike RNA . To convert the spike hybridization signals to ratios, an eighth sample was prepared, called the reference sample, consisting of the base Col RNA completed with all spike RNAs at a concentration of 100 cpc. The results from the eight experiments using the Affymetrix gene chips (ATH1) are available for analysis or download from this site. Experimenter name = Jim Beynon; Experimenter phone = 01798 470382; Experimenter fax = 01789 470552; Experimenter department = Horticulture Research International; Experimenter institute = Warwick University; Experimenter address = Horticulture Research International; Experimenter address = Wellesbourne; Experimenter address = Warwick; Experimenter zip/postal_code = CV34 6QJ; Experimenter country = UK Experiment Overall Design: 8 samples were used in this experiment
Project description:Expression profile comparison of peripheral blood lymphocytes (PBL) or haemopoietic stem cells (HSC) at the time of transduction with a gammaretroviral vector. The analysis is performed in the context of two different gene therapy clinical trials (Recchia et al, 2006; Aiuti et al, 2007) based on autologous infusion of human T cells or CD34+ haemopoietic progenitor cells gene-corrected with an moloney leukemia virus-derived vector (MLV-vector). T cells and CD34+ cells were isolated from patients and pre-stimulated in vitro with cytokines prior to transduction with the vector and re-infusion in patient. The expression profiles of T cells and CD34+ cells were analysed by microarray just after cytokine stimulation, providing information on the transcriptional activity of these two target cells at the time of transduction.
Project description:Woodchucks that were infected with WHC virus developed HCCs. HCCs and surrounding tissues were removed and RNA was extracted from microarray study. Human, rat and mouse arrays were used due to the lack of a woodchuck array. Same procedures and parameters were used to conduct this experiment. Experiment Overall Design: 3 woodchucks with HCCs were used. HCCs and their surrouding normal tissues were harvested. These 3 pairs of tissues were cross-species hybridized into a human, rat and mouse chip under same conditions. Data analysis were performed to compare the results.