PhD ceremony Ms. N.A. Hosper: The use of mesenchymal cells in fetal and adult tissue repair

PhD ceremony: Ms. N.A. Hosper, 12.45 uur, Academiegebouw, Broerstraat 5, Groningen

Dissertation: The use of mesenchymal cells in fetal and adult tissue repair

Promotor(s): prof. P.P. van den Berg, prof. R.A. Bank

Faculty: Medical Sciences

In this thesis cellular processes involved in fetal and adult tissue repair were studied. Such knowledge can be useful for the design of novel therapies with regard to e.g. spina bifida. Spina bifida is a congenital closure defect of the neural tube leading to neural damage. Such neural damage is caused by two hits; the ‘first’ is the failure of the neural tube to close and the ‘second’ hit is the exposure of the neural tissue to the amniotic fluid during pregnancy. Intra-uterine tissue engineering might reduce neural damage in spina bifida patients. We used collagen I matrices to close skin defects in a fetal sheep model. In this study we have demonstrated that collagen scaffolds can be used to treat fetal skin defects and that the combination of collagen scaffolds with growth factors vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF2) had a beneficial effect on fetal wound healing. Another option to improve wound healing can be the addition of stem cells to a scaffold. We have shown that human amniotic fluid cells from healthy fetuses can be used to repair skin defects. For future therapy it is important that autologous cells are used to prevent immunological complications. We found that neural tube defect amniotic fluid cells do not deposit collagen type I in vitro. This is a disadvantage when such cells are used for fetal tissue engineering. More research is required to conclude whether these cells are suitable for the treatment of spina bifida.