Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using a murine bone marrow transplantation model, we evaluated the long-term engraftment of retrovirally transduced bone marrow cells in nonmyeloablated hosts. Male bone marrow was stimulated in a cocktail of interleukin-3 (IL-3), IL-6, IL-11, and stem cell factor (SCF) for 48 hours, then cocultured on the retroviral producer line MDR18.1 for an additional 24 hours. Functional transduction of hematopoietic progenitors was detected in vitro by reverse transcriptase-polymerase chain reaction (RT-PCR) amplification of multiple drug resistance 1 (MDR1) mRNA from high proliferative potential-colony forming cell (HPP-CFC) colonies. After retroviral transduction, male bone marrow cells were injected into nonablated female mice. Transplant recipients received three TAXOL (Bristol-Myers, Princeton, NJ) injections (10 mg/kg) over a 14-month period. Transplant recipient tissues were analyzed by Southern blot and fluorescence in situ hybridization for Y-chromosome-specific sequences and showed donor cell engraftment of approximately 9%. However, polymerase chain reaction amplification of DNAs from bone marrow, spleen, and peripheral blood showed no evidence of the transduced MDR1 gene. RT-PCR analysis of total bone marrow RNA showed that transcripts from the MDR1 gene were present in a fraction of the engrafted donor cells. These data show functional transfer of the MDR1 gene into nonmyeloablated murine hosts. However, the high rates of in vitro transduction into HPP-CFC, coupled with the low in vivo engraftment rate of donor cells containing the MDR1 gene, suggest that the majority of stem cells that incorporated the retroviral construct did not stably engraft in the host. Based on additional studies that indicate that ex vivo culture of bone marrow induces an engraftment defect concomitantly with progression of cells through S phase, we propose that the cell cycle transit required for proviral integration reduces or impairs the ability of transduced cells to stably engraft.
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PMID:Cytokine-facilitated transduction leads to low-level engraftment in nonablated hosts. 922 88

In the present study, the effects of murine bone marrow endothelial cell conditioned medium (ECM) combined with flt3 ligand (FL) or/and thrombopoietin (TPO) on the proliferation of HPP-CFC and CFU-GM were investigated. Both ECM and the concentrated retentate of ECM (MW>10 kD) promoted the growth of CFU-GM and HPP-CFC, and this promoting effect was further enhanced by addition of FL or TPO. Using reverse transcriptase-polymerase chain reaction (RT-PCR) technique, the expression of FL and TPO mRNA was not found in murine bone marrow endothelial cells.
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PMID:[Effects of murine bone marrow endothelial cell conditioned medium in combination with FL and TPO on the growth of HPP-CFC and CFU-GM]. 1193 Feb 13

The t(9;22) (q34;q11) between abl and bcr genes plays a pivotal role in the diagnosis and pathogenesis of chronic myelogenous leukemia(CML). To explore the bcr/abl fusion mRNA expression on hematopoietic precursors, reverse transcriptase-polymerase chain reaction(RT-PCR) was applied to detect bcr/abl mRNA expression on bone marrow cell colonies. Meanwhile, bcr/abl mRNA expressions on 14- or 28-day colonies using HPP-CFC and CFU-GM semisolid agar culture assay were also determined in 4 cases of confirmed Ph-positive CML by karyotyping analysis. The results showed that the bcr/abl mRNA expressions on 14-day colonies and some 14- or 28-day colonies detected singly were positive at presentation by RT-PCR, in agreement with results by karyotype analysis. Thus, a sensitive and powerful technique was offered for studying gene expression on hematopoietic precursors, diagnosis and therapeutic monitoring of CML. Furthermore, this can be used as an ideal method for revealing molecular mechanisms of pathogenesis of CML and screening anti-CML drugs.
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PMID:[Detection of bcr/abl gene expression on bone marrow cell colonies in chronic myelogenous leukemia by reverse transcriptase-polymerase chain reaction]. 1208 Jun 71