Various fates of neuronal progenitor cells observed on several different chemical functional groups

Abstract

Neuronal progenitor cells cultured on gold-coated glass surfaces modified by different chemical functional groups, including hydroxyl (-OH), carboxyl (-COOH), amino (-NH₂), bromo (-Br), mercapto (-SH), -Phenyl and methyl (-CH₃), were studied here to investigate the influence of surface chemistry on the cells’ adhesion, morphology, proliferation and functional gene expression. Focal adhesion staining indicated in the initial culture stage cells exhibited morphological changes in response to different chemical functional groups. Cells cultured on -NH₂ grafted surface displayed focal adhesion plaque and flattened morphology and had the largest contact area. However, their counter parts on -CH₃ grafted surface displayed no focal adhesion and rounded morphology and had the smallest contact area. After 6 days culture, the proliferation trend was as follows: -NH₂>-SH>-COOH>-Phenyl>-Br>-OH>-CH₃. To determine the neural functional properties of the cells affected by surface chemistry, the expression of glutamate decarboxylase (GAD67), nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) were characterized. An increase of GAD67 expression was observed on -NH₂, -COOH and -SH grafted surfaces, while no increase in NGF and BDNF expression was observed on any chemical surfaces. These results highlight the importance of surface chemistry in the fate determination of neuronal progenitor cells, and suggest that surface chemistry must be considered in the design of biomaterials for neural tissue engineering.

Keywords

neuronal progenitor cell / cell adhesion / surface chemistry / GABAergic / neurotrophic factor