In the hematopoietic microenvironment, endothelial cells (ECs) play an important role in the regulation of hematopoietic cell proliferation and trafficking. We previously demonstrated that EC stimulated with tumor necrosis factor alpha (TNF-) induce the generation of dendritic cells from CD34(+) stem cells, whereas in contrast, interleukins were capable of inducing the proliferation of hematopoietic and myeloid progenitors.
Transcriptional profiling of the hematopoietic support of interleukin-stimulated human umbilical vein endothelial cells (HUVECs).
Specimen part, Treatment
View SamplesSynovial fibroblasts of 6 RA patients were treated with IL1 or PDGF-D. The aim of this study was to outline mechanism of the disease RA by a treatment with one of these cytokines.
Novel application of multi-stimuli network inference to synovial fibroblasts of rheumatoid arthritis patients.
Treatment, Subject, Time
View SamplesRheumatoid arthritis (RA) leads to progressive destruction of articular structures. Despite recent progress in controlling inflammation and pain, little cartilage repair has yet been observed. This in vitro study aims to determine the role of chondrocytes in RA-related cartilage destruction and antirheumatic drug-related regenerative processes. Human chondrocytes were three-dimensionally cultured in alginate beads. To determine the RA-induced gene expression pattern, human chondrocytes were stimulated with supernatant of RA synovial fibroblasts (RASF) and normal donor synovial fibroblasts (NDSF), respectively. To examine antirheumatic drug response signatures, human chondrocytes were stimulated with supernatant of RASF that have been treated with disease-modifying antirheumatic drugs (DMARD; azathioprine, sodium aurothiomalate, chloroquine phosphate, methotrexate), non-steroidal anti-inflammatory drugs (NSAID; piroxicam, diclofenac) or steroidal anti-inflammatory drugs (SAID; methylprednisolone, prednisolone). Genome-wide expression profiling with oligonucleotide microarrays was used to determine differentially expressed genes. Real-time RT-PCR and ELISA were performed for validation of microarray data. Following antirheumatic treatment, microarray analysis disclosed a reverted expression of 94 RA-induced chondrocyte genes involved in inflammation/NF-B signalling, cytokine/chemokine activity, immune response, proliferation/differentiation and matrix remodelling. Hierarchical clustering analysis showed that treatment of RASF with the DMARD azathioprine, gold sodium thiomalate and methotrexate resulted in chondrocyte gene expression signatures that were closely related to the healthy pattern. Treatment with the SAID methylprednisolone and prednisolone strongly reverted the RA-related chondrocyte gene expression, in particular the expression of genes involved in inflammation/NF-B and cytokine/chemokine activity. The NSAID piroxicam and diclofenac and the DMARD chloroquine phosphate had only moderate to marginal effects. Pathway analysis determined major mechanisms of drug action, for example pathways of cytokine-cytokine receptor interaction, TGF-/TLR/Jak-STAT signalling and ECM-receptor interaction were targeted. This in vitro study provides a comprehensive molecular insight into the antirheumatic drug response signatures in human chondrocytes, thereby revealing potential molecular targets, pathways and mechanisms of drug action involved in chondrocyte regeneration. Thus, the present study may contribute to the development of novel therapeutic chondro-protective compounds and strategies.
Antirheumatic drug response signatures in human chondrocytes: potential molecular targets to stimulate cartilage regeneration.
No sample metadata fields
View SamplesWe have studied the expression profile of 3D cultured human chondrocytes that were stimulated with supernatant of synovial fibroblasts derived from a RA patient (RASF=HSE cell line) and from a normal donor (NDSF=K4IM cell line), respectively. For this purpose, passage 2 human chondrocytes were cultured for 14 days in alginate beads and subsequently stimulated for 48 hours with supernatant of RASF and NDSF. Baseline expression was determined of unstimulated chondrocytes. Differential genome-wide microarray analysis of RASF and NDSF stimulated chondrocytes disclosed a distinct expression profile related to cartilage destruction involving marker genes of inflammation (COX-2), NF-kappa B signaling pathway (TLR2), cytokines/chemokines and receptors (CXCL1-3, CCL20, CXCL8, CXCR4, IL-6, IL-1beta), matrix degradation (MMP-10, MMP-12) and suppressed matrix synthesis (COMP). Thus, transcriptome profiling of RASF and NDSF stimulated chondrocytes revealed a disturbed catabolic-anabolic homeostasis of chondrocyte function. This study provides a comprehensive insight into the molecular regulatory processes induced in human chondrocytes during RA-related cartilage destruction.
Key regulatory molecules of cartilage destruction in rheumatoid arthritis: an in vitro study.
No sample metadata fields
View SamplesHuman adult mesenchymal stromal cells (hMSC) have the potential to differentiate into chondrogenic, adipogenic or osteogenic lineages, providing a potential source for tissue regeneration. An important issue for efficient bone regeneration is to identify factors that can be targeted to promote the osteogenic potential of hMSCs. Using transcriptomic analysis, we found that integrin alpha5 (ITGA5) expression is upregulated during dexamethasone-induced hMSCs osteoblast differentiation. Gain-of-function studies showed that ITGA5 promotes the expression of osteoblast phenotypic markers as well as in vitro osteogenesis in hMSCs. Downregulation of endogenous ITGA5 using shRNA blunted osteoblast marker expression and osteogenic differentiation. Pharmacological and molecular analyses showed that the enhanced hMSCs osteoblast differentiation induced by ITGA5 was mediated by activation of FAK/ERK1/2-MAPKs and PI3K signaling pathways. Remarkably, activation of ITGA5 using a specific antibody that primes the integrin or a peptide that specifically activates ITGA5 was sufficient to enhance ERK1/2-MAPKs and PI3K signaling and to promote osteoblast differentiation and osteogenic capacity of hMSCs. We also demonstrate that hMSCs engineered to over-express ITGA5 exhibited a marked increase in their osteogenic potential in vivo. These findings not only reveal that ITGA5 is required for osteoblast differentiation of adult human MSCs but also provide a novel targeted strategy using ITGA5 agonists to promote the osteogenic capacity of hMSCs, which may be used for tissue regeneration in bone disorders where the recruitment or capacity of MSCs is compromised.
Priming integrin alpha5 promotes human mesenchymal stromal cell osteoblast differentiation and osteogenesis.
Sex, Age, Specimen part, Treatment
View SamplesPreB cells were analyzed for differences in gene expression before and after the overexpression of miR-221. In order to dissect possible targets for the miR-221, gene expression profiles of preB cells un-induced or induced for the miR-221 expression after 8, 16 and 24 hours were compared. All induction time-points, e.g. after 8, 16 and 24 hours were compared to un-induced preB cells and to each other group.
SiPaGene: A new repository for instant online retrieval, sharing and meta-analyses of GeneChip expression data.
Specimen part
View SamplesThis study demonstrates quantitative and qualitative differences between type I IFN signatures in autoimmunity and viral infection using purified CD4pos T cells and CD16pos- and CD16neg-monocyte subsets. We were able to discriminate between cell-specific viral response signatures and the pathogenically amplified IFN signatures observed in autoimmunity. The differences were of both a qualitative and quantitative nature, as the signatures in the patients with SLE were characterized by much more complexly compiled gene patterns with increased absolute gene expression levels.
Cell-specific type I IFN signatures in autoimmunity and viral infection: what makes the difference?
Specimen part
View SamplesDiscrimination of rheumatoid arthritis (RA) patients from patients with other inflammatory/degenerative joint diseases or healthy individuals purely on the basis of genes differentially expressed in high-throughput data has proven very difficult. Thus, the present study sought to achieve such discrimination by employing a novel unbiased approach using rule-based classifiers. Three multi-center genome-wide transcriptomic data sets (Affymetrix HG- U133 A/B) from a total of 79 individuals, including 20 healthy controls (control group - CG), as well as 26 osteoarthritis (OA) and 33 RA patients, were used to infer rule- based classifiers to discriminate the disease groups. The rules were ranked with respect to Kiendls statistical relevance index, and the resulting rule set was optimized by pruning. The rule sets were inferred separately from data of one of three centers and applied to the two remaining centers for validation. All rules from the optimized rule sets of all centers were used to analyze their biological relevance applying the software Pathway Studio.
Identification of rheumatoid arthritis and osteoarthritis patients by transcriptome-based rule set generation.
Sex, Age
View SamplesHuman mesenchymal stem cells (MSC) display a high potential for the development of novel treatment strategies for cartilage repair. However, the pathways involved in their differentiation to functional and non hypertrophic chondrocytes remain largely unknown, despite the work on embryologic development and the identification of key growth factors including members of the TGF, Hh, Wnt and FGF families. In this study, we asked if we could identify specific biological networks independently from the growth factor used (TGF-3 or BMP-2). To address this question, we used DNA microarrays and performed large-scale expression profiling of MSC at different time points during their chondral differentiation. By comparing these data with those obtained during their differentiation into osteoblasts and adipocytes, we identified 318 genes specific for chondrogenesis. We distributed the selected genes in 5 classes according to their kinetic of expression and used the Ingenuity software in order to identify new biological networks. We could reconstruct 3 phases for chondral differentiation, characterized by functional pathways. The first phase corresponds to cell attachment and apoptosis prevention with the up-regulation of 5 integrins, BCL6, NFIL3, RGS2 and down-regulation of CTGF and CYR61. The second phase is characterized by a proliferation/differentiation step with the continuous expression of MAF, PGF, HGMA1 or NOTCH3, CHI3L1, WNT5A, LEPR. Finally, the last step of differentiation/hypertrophy is characterized by expression of DKK1, APOD/E, SERPINF1 and TIMP4. These data propose new pathways to understand the complexity of MSC differentiation to chondrocytes and new potential targets for cell therapy applied to cartilage repair.
Gene expression profile of multipotent mesenchymal stromal cells: Identification of pathways common to TGFbeta3/BMP2-induced chondrogenesis.
No sample metadata fields
View SamplesDiscrimination of rheumatoid arthritis (RA) patients from patients with other inflammatory/degenerative joint diseases or healthy individuals purely on the basis of genes differentially expressed in high-throughput data has proven very difficult. Thus, the present study sought to achieve such discrimination by employing a novel unbiased approach using rule-based classifiers. Three multi-center genome-wide transcriptomic data sets (Affymetrix HG- U133 A/B) from a total of 79 individuals, including 20 healthy controls (control group - CG), as well as 26 osteoarthritis (OA) and 33 RA patients, were used to infer rule- based classifiers to discriminate the disease groups. The rules were ranked with respect to Kiendls statistical relevance index, and the resulting rule set was optimized by pruning. The rule sets were inferred separately from data of one of three centers and applied to the two remaining centers for validation. All rules from the optimized rule sets of all centers were used to analyze their biological relevance applying the software Pathway Studio.
Identification of rheumatoid arthritis and osteoarthritis patients by transcriptome-based rule set generation.
Specimen part, Disease, Disease stage
View Samples