Hanna Dunay (Aachen, DE), Mattis Wachendörfer (Aachen, DE), Christoph Kuckelkorn (Aachen, DE), Prof. Dr. Horst Fischer (Aachen, DE)
Abstract text (incl. figure legends and references)
Introduction: Mesoangioblasts (MABs), a multipotent muscle tissue stem cell type, have the function to regenerate defective muscle tissue in vivo. It has been shown that this regeneration can also be stimulated by pre-isolated stem cells injected intra-arterially from outside. It is crucial for the efficiency of such a stem cell therapy that as many as possible of the externally added mesoangioblasts reach the site of the diseased tissue. Therefore, it must be investigated what significantly influences the transmembrane migration of this cell type through the endothelial layer of the blood vessel towards the surrounding muscle tissue. While the stimulating effect of the myoblasts has been shown in previous studies, the influence of smooth muscle cells, present in the arterial system, is yet unknown. Objectives: In order to mimic the in vivo conditions, an in vitro model has been developed in our lab within the framework of an EU collaborative project (grant EMR116), which is suitable to study the influence of various factors and thereby gain new insights into how the efficiency of the targeted in vivo stem cell therapy could be increased. Material and Methods: Transwell inserts of a Boyden chamber setup were covered with a monolayer of HUVECs. Smooth muscle cells were seeded in the lower wells at different concentrations and MABs were added to the inserts in suspension. Six hours after seeding, the migrated MABs were fixed and counted. Next to the effect of smooth muscle cells, the presence of the cytokines TNF-alpha and SDF-1 in the medium of the lower compartment was investigated. Results: The migration of MABs through HUVEC monolayers could be successfully stimulated. It was shown that the presence of smooth muscle cells as well as the inflammatory factors TNF-alpha and SDF-1 influence the transendothelial migration of MABs depending on their concentration. Conclusions: The findings could be a clue to improve the efficiency of a stem cell therapy in the future.