Effect of matrix metalloproteinases inhibition on the proliferation and differentiation of HUCB-NSCs cultured in the presence of adhesive substrates.

Cell adhesion to extracellular matrix (ECM) generates intracellular signals that modulate cell survival, proliferation, migration and differentiation. Because of its heterogeneous nature, ECM has the potential to induce unique responses that are composition-dependent. One approach to study the effect of ECM signals on cell development, independently on signals from other extracellular sources, has been to deprive cells of serum and to analyze the influence of specific ligands. In the current work we determine the potential of different ECM proteins (fibronectin, laminin, collagen) on the proliferation and differentiation of human umbilical cord blood-derived neural stem cells (HUCB-NSCs) cultured in serum-free conditions. The effect of tested ECM components on the above processes might be associated with the particular pattern of their proteolysis. In this context enzymes that are responsible for the modification of ECM proteins are of particular pertinence. Matrix metalloproteinases (MMPs) represent a family of enzymes known to play role in the modification of ECM and by this can change the cell-ECM substrate interaction, required for cell development. In an effort to elucidate the participation of MMPs in the proliferation and differentiation HUCB-NSCs were cultured in the presence or absence of MMPs inhibitors - GM6001 and doxycycline. Our results show that addition of the above inhibitors interfered with both the proliferation and differentiation of progenitor cells toward the neuronal lineage. This effect depends on the adhesive ECM substrate and is most pronounced in the presence of fibronectin and laminin. In conclusion, our results suggest that MMPs modulate interaction between HUCB-NSCs and their environment and therefore might be an important component in neurogenesis-associated processes.