Sensitivity of neural stem cells derived from human umbilical cord blood (HUCB-NSC) to developmental neurotoxin - methylmercury chloride: Dependence on non-specific and receptor mediated interactions with biomolecules

Human neural stem cells play an important role in in vitro developmental neurotoxicity testing. The purpose of this research was to investigate the sensitivity of neural stem cells derived from human umbilical cord blood (HUCB-NSC) to methylmercury chloride (MeHgCl), and its dependence on the type of interaction on cell membrane/biomolecule interface. MeHgCl is well known neurotoxin with documented adverse influence on human central nervous system (CNS) development. Cells were cultured in 96-well plates covered with different adhesive substrates or on Petri dishes microcontact-printed with biofunctional domains. The following biomaterials were used: poly-L-lysine, the synthetic compound, which allows to create electrostatic interactions with cells, or fibronectin and vitronectin, proteins of extracellular matrix, which create receptor mediated interactions between cells and the adhesive substrate. After the incubation with different concentrations of the neurotoxin, the cell viability, ability to proliferate, and to differentiate into neural precursors of HUCB-NSCs was measured with Alamar Blue assay and immunfluorescence stainings. High concentration of MeHgCl (1 µM) significantly decreased viability of cells and their ability to proliferate. The response of cells to the toxic effect of MeHgCl was different depending on the type of adhesive substrate. Domains covered with fibronectin or vitronectin, decreased significantly HUCB-NSC sensitivity to the neurotoxin when compared to poly-L-lysine. Our results suggest that receptor mediated interactions on cell membrane/biomolecule interface may be protective in neural stem cells’ response to certain neurotoxins. Supported by MSHE grant No 5978/B/P01/38 and NN 302663940