Evaluation of silicon nanoporous membranes and ECM-based microenvironments on neurosecretory cells.

Understanding the interactions between microfabricated synthetic interfaces and cultured cells expressing a neuronal phenotype are critical for advancing research in the field of neural engineering such as neural recording and stimulation and neural microdevice interactions with the human brain. Here we explore the integration of these two components for therapeutic applications of neural prostheses. Microfabricated silicon nanoporous membranes were investigated for their effects on survival, proliferation, and differentiation of the well-known PC12 clonal line. Specifically, cell morphology, examined through fluorescence staining, were comparable in many respects on both silicon membrane and widely-used polystyrene culture surfaces. The attachment and differentiation of PC12 cells cultured on collagen and laminin-modified membranes and standard tissue culture surfaces were similar. Lastly, the differentiation response and tyrosine hydroxylase activity of PC12 cells embedded in a type I collagen matrix on experimental membrane substrates while exposed to NGF were significant and indistinguishable from tissue-culture polystyrene (TC-PS) surfaces. Results from this research suggest that microfabricated silicon nanoporous membranes may be useful, biocompatible permselective structures for neuroprosthetic applications and that collagen may be a useful immobilizing matrix for PC12 cells loaded in implantable macroencapsulation devices designed for the treatment of neurodegenerative disorders.