Real-time monitoring of human Schwann cells on heparin-collagen coatings reveals enhanced adhesion and growth factor response

Abstract

In this work, we evaluate the enhancing effect of six bilayers of heparin/collagen (HEP/COL)₆ layer-by-layer coatings on human Schwann cell (hSCs) adhesion and proliferation in the presence or absence of nerve growth factor (NGF). hSCs behavior and in vitro bioactivity were studied during six days of culture using end-point viability and proliferation assays as well as an impedance-based real-time monitoring system. An end-point viability assay revealed that hSCs cultured on the (HEP/COL)₆ coatings increased their growth by more than 230% compared to controls. However, an EdU proliferation assay revealed that the proliferation rate of hSCs in all conditions were similar, with 45% of cells proliferating after 18 hours of incubation. Fluorescence microscopy revealed that hSCs spreading was similar between the tissue culture plastic control and the (HEP/COL)₆. The presence of NGF in solution resulted in cells with a larger spread area. Real-time monitoring of hSCs seeded on (HEP/COL)₆ with and without NGF reveals that initial cell adhesion is improved by the presence of the (HEP/COL)₆ coatings, and it is further improved by the presence of NGF. Our results suggest that (HEP/COL)₆ coatings enhance Schwann cell behavior and response to NGF. This simple modification could be applied to current nerve regeneration strategies to improve the repair of damaged nerve.