Project description:Systemic lupus erythematosus (SLE) is characterized by increased vascular risk due to premature atherosclerosis independent of traditional risk factors. We previously proposed that interferon-α plays a crucial role in premature vascular damage in SLE. IFN-α alters the balance between endothelial cell apoptosis and vascular repair mediated by endothelial progenitor cells (EPCs) and myeloid circulating angiogenic cells (CACs). Here we demonstrate that IFN-α promotes an antiangiogenic signature in SLE and control EPCs/CACs, characterized by transcriptional repression of IL-1α and β, IL-1 receptor 1 and vascular endothelial growth factor A (VEGF-A) and upregulation of IL-1 receptor antagonist (IL-1RN) and the decoy receptor IL1-R2. IL-1β promotes significant improvement in the functional capacity of lupus EPCs/CACs, therefore abrogating the deleterious effects of IFN-α. We used microarrays to analyze the effect of IFNα on peripheral blood EPCs/CACs and on bone marrow EPCs exposed to proangiogenic stimulation. This SuperSeries is composed of the SubSeries listed below. Human healthy and lupus EPCs and CACs from PBMCs, and healthy EPCs from bone marrow, were isolated and cultured under proangiogenic stimulation; after IFN-α incubation or not, RNA was extracted and processed for hybridization on Affymetrix microarrays.
Project description:Systemic lupus erythematosus (SLE) is characterized by increased vascular risk due to premature atherosclerosis independent of traditional risk factors. We previously proposed that interferon-α plays a crucial role in premature vascular damage in SLE. IFN-α alters the balance between endothelial cell apoptosis and vascular repair mediated by endothelial progenitor cells (EPCs) and myeloid circulating angiogenic cells (CACs). Here we demonstrate that IFN-α promotes an antiangiogenic signature in SLE and control EPCs/CACs, characterized by transcriptional repression of IL-1α and β, IL-1 receptor 1 and vascular endothelial growth factor A (VEGF-A) and upregulation of IL-1 receptor antagonist (IL-1RN) and the decoy receptor IL1-R2. IL-1β promotes significant improvement in the functional capacity of lupus EPCs/CACs, therefore abrogating the deleterious effects of IFN-α. We used microarrays to analyze the effect of IFNα on peripheral blood EPCs/CACs and on bone marrow EPCs exposed to proangiogenic stimulation. Human healthy EPCs from bone marrow were isolated and cultured under proangiogenic stimulation; after IFNa incubation or not, RNA was extracted and processed for hybridization on Affymetrix microarrays.
Project description:Background: In recent times a subset of bone marrow (BM) derived cells; endothelial progenitor cells (EPCs), have generated tremendous interest, as these cells are suggested to home to sites of neovascularization and neoendothelialization and differentiate into mature endothelial cells (ECs), a process referred to as postnatal vasculogenesis. EPCs are being considered as a potential regenerative tool for treating various pathophysiological disease states including cardiovascular disorder and as a possible target to restrict vessel growth in tumour pathology. However, conflicting results have been reported in the field due to lack of EPC specific biomarkers, and the identification, characterization, and the precise role of EPCs in vascular biology still remains a subject of great debate. Therefore, the objective of this study was to use a bioinformatics approach to identify putative novel EPC specific biomarkers. Methods: This study reports a detailed gene expression profile of human umbilical cord blood (UCB) derived non-adherent CD133 + cells at different time points during in vitro differentiation (day 4 and day 7) which were compared with differentiated donor matched human umbilical vein endothelial cells (HUVEC). Results: EPC gene expression was profiled at both days 4 and 7, using affymetrix human 1.0ST exon arrays. Affymetrix gene expression profiling revealed significant expression changes in genes associated with stem/progenitor cell properties such as adhesion, signalling, molecular transport, cell structure organisation and growth. Conclusions: This is the first study utilizing gene expression profiling to examine non adherent CD133+ progenitor cells. Alterations in the gene expression reported in this study may be involved in the cellular processes characteristic of EPC development and differentiation. Gene expression profiling was performed on EPCs cultured for D4 and D7, on Affymetrix human 1.0ST exon array chips. Gene Spring (version GX11) was used to perform the gene expression analysis on three experimental groups; (a) D4 EPCs versus HUVEC; (b) D7 EPCs versus HUVEC and (c) D4 versus D7 EPCs.