Medizinische Universität Graz - Research portal
Selected Publication:
Schweizer-Trummer, A.
Differenzierungspotential von humanen fetalen und adulten Endothelzellen.
[ Diplomarbeit/Master Thesis ] Karl-Franzens University Graz; 2008.
- Authors Med Uni Graz:
- Schweizer-Trummer Angela
- Advisor:
- Lang-Olip Ingrid
- Altmetrics:
- Abstract:
- Abstract The aim of this masterthesis was to determine the differences between human fetal and adult arterial and venous endothelial cells and to investigate their stem cell or differentiation potential. Additionally, it was investigated if this potential was tissue-specific and if hypoxia induced or enhanced this potential. Fetal arterial (f-AEC) and venous (f-VEC) endothelial cells from term placenta and adult arterial (a-AEC) and venous (a-VEC) endothelial cells originating from different organs (mesen-teries, ilia) were isolated by enzymatic perfusion of corresponding blood vessels and cultured under standard (20% 02), hypoxic (2%, 3%, 8% 02), adipogenic and osteogenic conditions. Morphological changes were evaluated by phase contrast microscopy. The proliferative activity and the cell viability were determined using Casy-system. The stem cell potential was inves-tigated by immunocytochemistry and reverse transcriptase polymerase chain reaction RT-PCR. Adipogenic and osteogenic differentiation of the cells were demonstrated by Oil Red 0, Alizarin Red S staining and scanning electron microscopy. This study demonstrates that f-AEC and a-AEC show a polygonal phenotype forming clas-sical cobblestone monolayers under standard culture conditions, whereas f-VEC and a-VEC are more spindle-shaped cells growing closely apposed to each other. VEC have a higher prolifera-tion potential than AEC. Under hypoxic conditions, all cell types increase in their cell sizes. The proliferation potential of endothelial cells under severe hypoxic conditions (2% 02, 3% 02) is decreased, but varies under moderate hypoxic conditions (8% 02), depending on cell type. The viability of endothelial cells varies under severe hypoxic conditions, but increases in all cell types under moderate hypoxic conditions. The stem cell antigens are increased (SSEA-4, CD133) or decreased (Oct-4, Sox-2, Nanog, CD34, CD 14) under hypoxic conditions. VEC mostly show a higher expression of stem cell markers than AEC and fetal endothelial cells show a higher ex-pression than adult endothelial cells. Adipogenic and osteogenic induction resulted in more than 50% of the f-VEC differentiated into adipoeytes or osteoblasts, respectively. In contrast, f-AEC, a-AEC, and a-VEC did not contain any or only very few lipid droplets and calcium deposits after induction treatment. These data provide evidence for the plasticity of endothelial cells derived from fetal and adult tissues. Hypoxia clearly induced morphological and functional changes on all endothelial cell types studied. The different proliferationpotential and viability of endothelial cells under all tested hypoxic conditions could be a hint for their tissue-specifity. The higher expression of stem cell markers on VEC and in particular the adipogenic and osteogenic differentiation potential of f-VEC may indicate the role of VEC as tissue-resident endothelial progenitors.