Project description:Introduction: There is a clinical need for developing systemic transplantation protocols for use of human skeletal stem cells (also known bone marrow stromal stem cells) (hBMSC) in tissue regeneration. In systemic transplantation studies, only a limited number of hBMSC home to injured tissues suggesting that only a subpopulation of hBMSC possess âhomingâ capacity. Thus, we tested the hypothesis that a subpopulation of hBMSC defined by ability to form heterotopic bone in vivo, is capable of homing to injured bone. Methods: We tested ex vivo and in vivo homing capacity of a number of clonal cell populations derived from telomerized hBMSC (hBMSC-TERT) with variable ability to form heterotopic bone when implanted subcutaneously in immune deficient mice. In vitro transwell migration assay was used and in vivo homing ability to bone fractures in mice was visualized by bioluminescence imaging (BLI). In order to identify the molecular phenotype associated with enhanced migration, we carried out comparative DNA microarray analysis of gene expression of hBMSC-derived high bone forming (HBF) clones versus low bone forming (LBF) clones. Results: In this study, clonal cell populations forming in vivo bone were shown to exhibit higher ex vivo transwell migration and following intravenous infusion, enhanced in vivo homing ability to bone fractures. Comparative microarray analysis of LBF versus HBF clones identified a significant enrichment of gene categories of cell chemo-attraction, adhesion and migration. Among these genes, platelet-derived growth factor receptor (PDGF-R) Î± and Î² were highly expressed in HBF clones. Further studies showed that the chemoattractive effects of PDGF in vitro was more enhanced in HBF clones compared to LBF clones and this effect was abolished in presence of a PDGFR-Î²-specific inhibitor: SU-16f. Sorted PDGFR-Î²+ cells from LBF clones showed that the PDGFR-Î²+ enriched cell population exhibited strong chemoattractance towards PDGF. Conclusion: Our data demonstrate phenotypic and molecular association between in vivo bone formation and migratory capacity of hBMSC. PDGFR-Î² can be used as a potential marker for the prospective selection of hBMSC populations with high migration and bone formation capacities suitable for clinical trials for enhancing bone regeneration. Total RNA obtained from telomerized human bone marrow derived mesenchymal stromal cells (T4P38a) with high in vivo bone forming capacity and (T4P74a) with low bone forming capacity and three single cell clones with high bone forming capacities (DD8, AD10 and BB10) and three clones with low bone forming capacities (CF1, CB4 and CD4). All cells were cultured under standard conditions and RNAs were isolated at baseline with no induction. each sample was represented in doublicate as a and b.

Project description:Introduction: There is a clinical need for developing systemic transplantation protocols for use of human skeletal stem cells (also known bone marrow stromal stem cells) (hBMSC) in tissue regeneration. In systemic transplantation studies, only a limited number of hBMSC home to injured tissues suggesting that only a subpopulation of hBMSC possess “homing” capacity. Thus, we tested the hypothesis that a subpopulation of hBMSC defined by ability to form heterotopic bone in vivo, is capable of homing to injured bone. Methods: We tested ex vivo and in vivo homing capacity of a number of clonal cell populations derived from telomerized hBMSC (hBMSC-TERT) with variable ability to form heterotopic bone when implanted subcutaneously in immune deficient mice. In vitro transwell migration assay was used and in vivo homing ability to bone fractures in mice was visualized by bioluminescence imaging (BLI). In order to identify the molecular phenotype associated with enhanced migration, we carried out comparative DNA microarray analysis of gene expression of hBMSC-derived high bone forming (HBF) clones versus low bone forming (LBF) clones. Results: In this study, clonal cell populations forming in vivo bone were shown to exhibit higher ex vivo transwell migration and following intravenous infusion, enhanced in vivo homing ability to bone fractures. Comparative microarray analysis of LBF versus HBF clones identified a significant enrichment of gene categories of cell chemo-attraction, adhesion and migration. Among these genes, platelet-derived growth factor receptor (PDGF-R) α and β were highly expressed in HBF clones. Further studies showed that the chemoattractive effects of PDGF in vitro was more enhanced in HBF clones compared to LBF clones and this effect was abolished in presence of a PDGFR-β-specific inhibitor: SU-16f. Sorted PDGFR-β+ cells from LBF clones showed that the PDGFR-β+ enriched cell population exhibited strong chemoattractance towards PDGF. Conclusion: Our data demonstrate phenotypic and molecular association between in vivo bone formation and migratory capacity of hBMSC. PDGFR-β can be used as a potential marker for the prospective selection of hBMSC populations with high migration and bone formation capacities suitable for clinical trials for enhancing bone regeneration.

Project description:The treatment of bone defects caused by infection, trauma or neoplasms remains a clinical challenge. Autologous bone transplantation is limited by availability, donor site morbidity and surgical risk factors. This has given rise to stromal/stem-cell based therapy. Bone marrow derived stromal cells (BMSCs) have been studied to a large extent and show high regenerative potential but their use is limited by availability, donor site morbidity and the relatively low cell yield as they represent only <0.1% of cell harvested from bone marrow aspirate. At the same time, they are the closest mesenchymal stromal cells for bone tissue engineering given their tissue origin and, unlike other mesenchymal stromal cells, can support the formation of hematopoietic marrow. Adipose tissue derived stromal cells (ASCs) as part of the stromal vascular fraction of adipose tissue can as well undergo osteogenic differentiation but can be additionally isolated in a sufficient quantity from lipoaspirate after liposuction of abundant subcutaneous fat tissue. Here, it has been shown that there are no major differences in regard to proliferation or differentiation capacity of ASCs derived from subcutaneous fat of different anatomical regions. It has been shown that BMSCs are more prone to senescence during expansion and passage than ASCs and that ageing impacts proliferative capabilities of BMSCs more than that of ASCs while it has also been reported that osteogenic differentiation capacity is least impacted by age. Multiple studies have compared the characteristics of these two mesenchymal stromal cells in regard to bone tissue engineering in vitro. Most studies point to inferior extracellular matrix mineralization and lower expression of key osteogenic transcription markers like Runx2 in osteogenic differentiated ASCs compared to BMSCs. On the other hand, a study by Rath et al. found contrary results using particular culturing conditions like 3D bioglass scaffolds. An intraindividual comparison of human MSCs of three donors cultured on decellularized porcine bone confirmed superior osteogenic capacity of BMSCs compared to ASCs. In contrast to BMSCs, ASCs were not able to induce heterogenic ossification in a mouse model. In a sheep tibia defect model application of BMSCs resulted in a significantly higher amount of newly formed bone tissue. Importantly, Osteogenic differentiated ASCs do not support the formation of a hematopoietic marrow. Proteomics enables large-scale analysis of proteins present in a cell type and can be used to identify differentially regulated key proteins in a comparative approach. A comparative proteomic analysis of BMSCs and ASCs by Roche et al. in 2009 identified 556 proteins with 78% of these not being differentially regulated between these two cell populations, regarded as high similarity. Another comparative proteomic study of 2016 by Jeon et al. found 90 differentially regulated proteins out of 3000 total identified proteins. Both studies do not specify a number of different tissue donors and in part using cell lines. Looking for differences upon osteogenic differentiation, transcriptomic comparison of osteogenic differentiated porcine ASCs and BMSCs has been performed, resulting in 21 differentially expressed genes after 21 days of osteogenic culture conditions. Still, it remains unanswered, which are the key distinctive features of osteogenic differentiated ASCs and BMSCs at protein level that might help address the abovementioned weaknesses of ASCs in bone tissue engineering/regeneration for translational research. To overcome this need, an intraindividual comparative DIA based proteomic analysis of osteogenic differentiated human BMSC and ASCs was performed in this study.

Project description:Direct contact with mesenchymal stromal impacts on migratory behavior and gene expression profile of CD133+ hematopoietic stem cells during ex-vivo expansion Objective: To investigate the impact of direct contact between mesenchymal stromal cells (MSCs) and CD133+ hematopoietic stem cells (HSCs) in terms of expansion potential differentiation, migratory capacity and gene expression profile. Methods: CD133+ purified HSCs were cultured for 7 days on subconfluent MSCs supplemented with growth factor containing medium. After ex-vivo expansion, non-adherent and adherent cells were collected and analyzed separately. Results: The adherent cells were found to have a more immature phenotype compared to the non-adherent fraction. CXCR4 was up regulated in the adherent fraction which was associated with a higher migration capacity towards a SDF-1 gradient. CFU-GM and LTC-IC assays demonstrated a higher clonogenicity and repopulating capacity of the adherent fraction. Genes involved in adhesion, cell cycle control, motility, self-renewal and apoptosis were expressed at a higher level in the adherent fraction. Conclusion: Adhesion and direct cell-cell contact with a MSC feeder layer supports ex-vivo expansion, migratory potential and stemness of CD133+ HSCs. Keywords: co-culture hematopoietic stem cells (HSCs) on mesenchymal stromal cells (MSCs) Non-adherent and adherent fractions from three independent experiments were isolated and collected. Cells were stabilized in PreProtct™ buffer (Miltenyi Biotec, Germany) and stored at -80ºC. Samples were shipped to Miltenyi Biotec (Bergisch Gladbach, Germany) a Whole Human Genome expression analysis. Briefly RNA was extracted and overall quality of total RNA samples was checked via the Agilent 2100 Bioanalyzer platform (Agilent Technologies). RNA samples were amplified and labelled using the Agilent Low RNA Input Linear Amp Kit (Agilent Technologies). Non-adherent samples were pooled as “Non-adherent pool” and adherent samples were pooled as “adherent pool” and labelled with Cy3 and Cy5, respectively. Fluorescence signals of the hybridized Agilent Oligo Microarrays were detected using Agilent’s DNA microarray scanner and the microarray image files were processed with The Agilent Feature Extraction Software (FES).

Dataset Information

Homo sapiens

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets