Project description:Expression of P190 and P210 BCR/ABL1 in normal human CD34(+) cells induces similar gene expression profiles and results in a STAT5-dependent expansion of the erythroid lineage The P190 and P210 BCR/ABL1 fusion genes are mainly associated with different types of hematologic malignancies, but it is presently unclear whether they are functionally different following expression in primitive human hematopoietic cells. We investigated and systematically compared the effects of retroviral P190 BCR/ABL1 and P210 BCR/ABL1 expression on cell proliferation, differentiation, and global gene expression in human CD34(+) cells from cord blood. Expression of either P190 BCR/ABL1 or P210 BCR/ABL1 resulted in expansion of erythroid cells and stimulated erythropoietin-independent burst-forming unit-erythroid colony formation. By using a lentiviral anti-signal transducer and activator of transcription 5 (STAT5) short-hairpin RNA, we found that both P190 BCR/ABL1- and P210 BCR/ABL1-induced erythroid cell expansion were STAT5-dependent. Under in vitro conditions favoring B-cell differentiation, neither P190 nor P210 BCR/ABL1-expressing cells formed detectable levels of CD19-positive cells. Gene expression profiling revealed that P190 BCR/ABL1 and P210 BCR/ABL1 induced almost identical gene expression profiles, and we identified a common set of 222 differentially expressed genes. Our data suggest that the early cellular and transcriptional effects of P190 BCR/ABL1 and P210 BCR/ABL1 expression are very similar when they are expressed in the same human progenitor cell population, and that STAT5 is an important regulator of BCR/ABL1-induced erythroid cell expansion. Keywords: global gene expression profiling, BCR/ABL1, CD34+ cord blood cells, CML, Ph+ ALL
Project description:The 8p11 myeloproliferative syndrome (EMS), also referred to as the stem cell leukemia/lymphoma syndrome, is a chronic myeloproliferative disorder that rapidly progresses into an acute leukemia. Molecularly, EMS is characterized by fusion of various partner genes to the FGFR1 gene, resulting in constitutive activation of the tyrosine kinase activity within FGFR1. The two most common fusion genes in human EMS are ZMYM2/FGFR1 (previously known as ZNF198/FGFR1) and BCR/FGFR1. To study the transcriptional programs becoming deregulated by the FGFR1 fusion genes, global gene expression analysis on human CD34+ cord blood cells expressing either of the fusion oncogenes ZMYM2/FGFR1 and BCR/FGFR1 was performed. As a reference gene we also included the more studied BCR/ABL1 fusion oncogene associated with chronic myeloid leukemia. We found that the 3 different fusion oncogenes had in common the upregulation of several genes involved in the JAK/STAT signalling pathway and also other sets of genes. However, the gene expression profiles were not identical, suggesting that both the tyrosine kinase containing gene and the partner gene would affect the transcription of downstream target genes. Bicistronic retroviral murine stem cell virus (MSCV) vectors expressing ZMYM2/FGFR1, BCR/FGFR1or P210 BCR/ABL1 and GFP were used. The MIG control vector expressed GFP only. Two days post transfection of human CD34+ umbilical cord blood cells, GFP-sorted cells were collected in three biological replicates and RNA was isolated immediately. In total, 12 samples were hybridized and scanned.
Project description:AML1-ETO expression in normal human umbilical cord blood CD34+ cells leads to long-term proliferation of an early self-renewing primitive progenitor cell with multilineage potential and stem cell ability, but these cells do not induce leukemia in immunodeficient mice. This comparative microarray study was initiated to determine the differences in the transcriptome of AML-ETO-expressing CD34+ cells after extended culture in vitro, using normal cord blood cells expanded for 6-8 weeks in vitro and subsequently purified for the CD34+ population as the control comparison. Experiment Overall Design: We have established a culture system whereby we retrovirally transduce human CD34+ cells, obtained from cord blood, with the leukemia fusion gene AML1-ETO. Cells expressing this fusion protein are able to proliferate long-term in vitro in a cytokine dependent manner. AML1-ETO-expressing cord blood cells have a large population of primitive self-renewing CD34+ cells with continued abnormal differentiation. We grow these cells in serum-free conditions using the BIT supplement from Stem Cell Technologies. For the current experiments we used cell cultures that had been proliferating in vitro for 8-12 weeks, in a cytokine cocktail of SCF, TPO, FLT3L, IL-6 all at 20 ng/mL and IL-3 at 10 ng/mL. Control cord blood samples that were CD34 purified were expanded for 5-8 weeks in the same culture media as used for AML1-ETO cells. All samples were magnetically selected for the CD34+ population, returned to culture, and one week later again selected for CD34+ cells and then lysed for RNA isolation.
Project description:Compare the gene expression profile among human CD34+ cord blood cells infected with MIGR1, MIGR1-AML1-ETO or MIGR1-AML1-ETO∆NHR1 AML1-ETO promotes the self-renewal of human hematopoietic stem/progenitor cells (HSPCs). We found deletion of NHR1 domain abrogates AML1-ETO induced expasion of HSPCs. GFP+CD34+ human cord blood cells were sorted by FACS 72 hours after the infection for RNA extraction and hybridyzation for Affymetrix microarrays.
Project description:Cells obtained from adipose tissue are able to differentiate into megakaryocytes. We compared the gene expression profile of human adipose tissue derived megakaryocytes with that of megakaryocytes differentiated from human CD34 positive cord blood hematopoietic stem cells.
Project description:AML1-ETO expression in normal human umbilical cord blood CD34+ cells leads to long-term proliferation of an early self-renewing primitive progenitor cell with multilineage potential and stem cell ability, but these cells do not induce leukemia in immunodeficient mice. This comparative microarray study was initiated to determine the differences in the transcriptome of AML-ETO-expressing CD34+ cells after extended culture in vitro, using normal cord blood cells expanded for 6-8 weeks in vitro and subsequently purified for the CD34+ population as the control comparison. Keywords: Disease state analysis; comparison of changes in transcriptome due to long-term AML1-ETO expression in normal human hematopoietic CD34+ progenitor cells
Project description:Global gene expressions of human cord blood-derived 18Lineage-negative (18Lin-)CD34+CD38-CD133+GPI-80+ cells (CD34+ HSCs), 18Lin-CD34-CD133+GPI-80+ cells (CD34- HSCs) and 18Lin-CD34+CD133- cells (non-HSCs) were analyzed. Results provide an insight into the molecular mechanisms underlying the self-renewal, maintenance and differentiation of human cord blood-derived CD34+/- HSCs.
Project description:Transcriptomic profile of CD34+ cells circulating in peripheral blood of TCIRG1-mutated osteopetrotic patients, compared to cord blood and mobilized CD34+ cells
Project description:To evaluate the long-term growth potential of BCR-ABL-transduced primitive human hematopoietic cells, lin- cord blood cells containing an MSCV-BCR-ABL-IRES-GFP (BCR-ABL) or control-GFP transgene (MIG) were injected IP into fetal goats at 45-55 days of gestation. Six transplant goats were born alive. One was examined three weeks after birth and showed GFP+ cells in the blood, bone marrow (BM), liver, kidney, lung, heart, and both skeletal and smooth muscle. FISH analysis also showed the liver of this goat contained BCR-ABL-GFP transgenic cells. The remaining five goats appear normal although, in some, the WBC count is elevated 3- to 5-fold. GFP+ cells, including cells identifiable by FACS as human CD34+ cells, have been detected in the blood of all these goats. The presence of BCR-ABL-GFP transgenic cells in the BM and liver was confirmed by FISH analysis, and quantitative real-time PCR analysis of genomic DNA isolated from unpurified BM cells obtained from three of the transplant goats demonstrated 3-5Ã104 copies of the transgene per microgram of DNA. Microarray transcript profiling was performed on blood and liver tissues of normal goats, BCR-ABL chimeric goats, MIG chimeric goats, and normal human samples. RNA for human genes was detected in goats transplanted with cord blood cells but not in normal goats, and the RNA abundance of some genes in BCR-ABL chimeric goat blood was similar to or greater than levels observed in MIG goat blood or normal human samples. Quantitative RT-PCR confirmed the differential expression of several genes in goats carrying the BCR-ABL vs. control transgene. These results demonstrate long-term engraftment but slow expansion in a large animal model of primitive human hematopoietic cells transduced with a BCR-ABL fusion gene and transplanted in utero. This novel xenotransplant goat model should be useful for analyzing the initial phases of development of human CML and for assessing new therapies with potential long-term benefits. Experiment Overall Design: Total RNA was extracted from liver (L) and blood (B) samples of normal goats (ng), humans (hu), chimeric goats engrafted with human cord blood stem cells containing control (mig) vector, and chimeric goats engrafted with CML (bcrabl) vector. RNA samples were profiled on Affymetrix human U133A GeneChips and examined for differentially expressed genes in CML vs control goats, filtering for signals significantly above background levels observed in normal goat to select for specific human gene expression.