Proliferation capacity of cord blood derived neural stem cell line on different micro-scale biofunctional domains

Physical interactions of cells with the adhesive substrates of the microenvironment as well as the presence of the soluble growth factors are important for the proliferation capacity of neural stem cells. We have used biofunctionalized surface domains microcontact printed with either synthetic polyaminoacid poly-L-lysine or extracellular matrix (ECM) component such as fibronectin, to study the proliferation capacity of human umbilical cord blood-derived neural stem cells (HUCB-NSC). The proliferation measured by the expression of Ki-67 protein was accompanied by the investigation of the cell morphology under the transmission and scanning electron microscopy in different culture time, plating densities of cells and medium condition (serum-free or 2 percent of FBS). The poly-L-lysine domains of defined micro-scale area promoted the presence of round, loosely attached Ki-67-positive cells, while fibronectin domains of the same size allowed appearance of flattened, strongly attached cells with more differentiated phenotype. These results were in agreement with the non-specific, electrostatic type of interaction between cell and substrate on poly-L-lysine and integrin receptor-mediated specific adhesion on fibronectin. In this report we have described in vitro culture conditions, which allow for immobilization of the non-differentiated and highly proliferating population of neural stem/progenitor cells to the biofunctionalized surface. The microarrays with bioactive domains allocating non-differentiated and proliferating neural stem/progenitor cells may find application for drug and chemicals toxicology screening of diverse factors influencing neural development.