Project description:We have recently established a self-renewing immortalized megakaryocyte progenitor cell lines (imMKCLs) from hiPSCs, displaying long-term expansion capability with yields of functional platelets (Nakamura et al. Cell Stem Cell, 2014). However, the platelets production using imMKCLs have not been fully sufficient or cost-effective for clinical application, and further improved culture conditions are needed to accomplish the industrialization of hiPSCs-derived platelets. We screened c-MPL agonists and identified TA-316 as the most potent compound that increases platelet productivity using imMKCLs more efficiently and cost effectively as compared to TPO. Gene microarrays were used to observe the global gene expression in imMKCLs cultured with TPO or TA-316 and identified distinct classes of up or down-regulated genes.
Project description:TPO mimetics have been shown to activate TPO receptor, the downstream JAK-STAT pathway, and induce differentiation of hematopoietic stem cells into megakaryocytes. However, the action of these TPO mimetics is initiated by binding to the transmembrane domain of the TPO receptor, which is distinct from the binding site of the native ligand, TPO. To determine whether TPO mimetics can differentiate hematopoietic stem cells into the same megakaryocytes as native TPO does, we performed a microarray experiment to compare the globe gene expression in purified CD61+ cells derived from TPO or TPO mimetic treated CD34+ bone marrow cells. Keywords: Drug Treatment
Project description:Small molecular TPO mimetics, LGD-4665 and eltrombopag, were efficacious in stimulating the formation of CD41+ cells from human bone marrow CD34+ cells. To better understand the mechanism of action of TPO mimetics, a microarray study was performed to compare global gene expression in CD34+ cells induced by small molecular TPO mimetics eltrombopag and LGD4665, to changes in response to recombinant human thrombopoietin (TPO). Keywords: Drug Treatment
Project description:Class I cytokine receptors such as Thrombopoietin receptor (MPL) are dimers, but it is unclear whether remodeling receptor dimer topology is a viable strategy to "tune" signaling output. We utilized diabodies (DA) as surrogate ligands in a prototypical dimeric receptor-ligand system, the cytokine Thrombopoietin (TPO) and its receptor (TpoR), to dimerize TpoR ectodomains in non-native architectures. Diabody-induced signaling amplitudes varied from full to minimal agonism. Here we describe a single-cell transcriptome analysis of 659 human Hematopoietic Stem Cells cultured with different DA. We find several difference between differentiation and activation of signaling pathways compared to TPO.
Project description:In order to examine the mechanism of TPO on cardiac protection against myocardial infarction damage (MI), we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to delineate the TPO cardioprotective mechanism against infarction.
Project description:JAK2 activation by TPO study and its downstream targets STAT1, STAT3 and STAT5 on Mouse HPC7 stem cells on four time points. The aim is to verify wether a JAK/STAT signalling signature is similar to the age-related functional decline in the haematopoietic system.
Project description:In order to examine the mechanism of TPO on cardiac protection against myocardial infarction damage (MI), we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to delineate the TPO cardioprotective mechanism against infarction. MI and TPO induced gene expressions in rat heart were measured at week 4. Two biological replicates were performed for each treatment group.
Project description:In order to examine the mechanism of TPO on cardiac protection against DOX damage, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to delineate the TPO cardioprotective mechanism against DOX-induced cardiomyopathy
Project description:In order to examine the mechanism of TPO on cardiac protection against DOX damage, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to delineate the TPO cardioprotective mechanism against DOX-induced cardiomyopathy Dox and TPO induced gene expressions in rat heart were measured at day 6. Two biological replicates were performed for each treatment group.
