Project description:Direct cell conversion is now expected to apply to therapeutic purposes. Although that has been succeeded in several cell types, the mechanism or general way to identify the key transcription factors are still unclear. In addition, most of the cases are not completely identical with the target cells. In previous work, we suggested that cell status is maintained by a homeostatic network of limited number of TFs and no single transcription factor is both necessary and sufficient to drive the differentiation process. Here, identifying the key TFs of human monocyte by combining comparative gene expression analysis and literature based text-mining, we mimicked the monocytic regulatory network in human dermal fibroblasts to induce direct cell conversion of the fibroblasts to monocytes. We suggested that although it is a primary master TF, single TF is not sufficient to induce the direct cell conversion and orchestrated TF regulation is necessary to complete the cell conversion. Total RNA obtained from human dermal fibroblasts(FIB), human CD14+ monocytes(MON), mock lentivirus vector transduced fibroblasts (FIB-mock), SPI1 transduced fibroblasts (FIB-SPI1), and SPI1, CEBPA, MNDA, IRF8 transduced fibroblasts(FIB-4Fs). The fold change was computed compared with fibroblasts or FIB-mock.
Project description:we simultaneously deconstructed fibroblastic TRNW and reconstituted monocytic TRNW, and analyzed its monocytic and fibroblastic gene expression in comparison with that of fibroblastic TRNW deconstruction only or monocytic TRNW reconstitution only. This study provides an explicit example demonstrating how two networks together regulate gene expression during cell reprogramming processes.
Project description:Transdifferentiation has been recently described as a novel method for converting human fibroblasts into induced cardiomyocyte-like cells. Such an approach can produce differentiated cells to study physiology or pathophysiology, examine drug interactions or toxicities, and engineer tissues. Here we describe the transdifferentiation of human dermal fibroblasts towards the cardiac cell lineage via the induced expression of transcription factors (TFs) GATA4, TBX5, MEF2C, MYOCD, NKX2-5, and delivery of microRNAs miR-1 and miR-133a. Cells undergoing transdifferentiation expressed ACTN2 and TNNT2 and partially organized their cytoskeleton in a cross-striated manner. The conversion process was associated with significant upregulation of a cohort of cardiac-specific genes, activation of pathways associated with muscle contraction and physiology, and downregulation of fibroblastic markers. We used a genetically encoded calcium indicator and readily detected active calcium transients although no spontaneous contractions were observed in transdifferentiated cells. Finally, we determined that inhibition of Janus kinase 1, inhibition of glycogen synthase kinase 3, or addition of NRG1 significantly enhanced the efficiency of transdifferentiation. Overall, we describe a method for achieving transdifferentiation of human dermal fibroblasts into induced cardiomyocyte-like cells via transcription factor overexpression, microRNA delivery, and molecular pathway manipulation.
Project description:Direct cell conversion is now expected to apply to therapeutic purposes. Although that has been succeeded in several cell types, the mechanism or general way to identify the key transcription factors are still unclear. In addition, most of the cases are not completely identical with the target cells. In previous work, we suggested that cell status is maintained by a homeostatic network of limited number of TFs and no single transcription factor is both necessary and sufficient to drive the differentiation process. Here, identifying the key TFs of human monocyte by combining comparative gene expression analysis and literature based text-mining, we mimicked the monocytic regulatory network in human dermal fibroblasts to induce direct cell conversion of the fibroblasts to monocytes. We suggested that although it is a primary master TF, single TF is not sufficient to induce the direct cell conversion and orchestrated TF regulation is necessary to complete the cell conversion.
Project description:Analysis of the effects of AVS023 and its active compounds (gallic acid and piperine) on human gene expression in primary human dermal fibroblasts induced by IL-1β. The results provided up- and down- regulated genes resulting from IL-1β and IL-1β plus with each test compound in primary human dermal fibroblasts
