Conclusion 46 5. Conclusions and Outlook We conclude that the oxygen level during cell culture has a profound impact on the cell characteristics, cell migration and integrin expression of hMSCs. Hypoxic cell culture conditions enhance cell proliferation, cell metabolism and prolong stemness of human mesenchymal stem cells in vitro. Furthermore, hypoxia during cell culture leads to increased cell migration. This is especially pronounced on collagen I and laminin coated surfaces. Additionally, hypoxia leads to differences in integrin expression. In a future study, we will evaluate oxygen-dependent differences in the cytoskeleton such as actin fibres and how these changes possibly affect biophysical characteristics of the cell. Furthermore, we will increase the efforts to understand oxygen dependent differences in migration and invasion of hMSCs, since these are the prerequisite for tissue repair. Finally, we will enlight selected integrin pathways. Especially the correlation between HIF-1α and integrin expression is of great interest, since HIF-1α is a key factor in response to hypoxia. We thereby hope to reveal new information concerning cell-cell or cell-matrix interaction and communication in hypoxic conditions.
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