Interfacing Synthetic Materials to Human Stem Cells

Scientists and engineers, frequently, prepare or utilize biologically compatible or active materials (simply biomaterials) to influence biological systems. When taking into account the complexity involving biological systems it is critical that surface and cellular properties are well understood all the way down to a single molecule or even an element. Synthetically well-defined objects influencing the fate of living mammalian cell systems, thus, can lead to the development of biomedical technologies and tools that can effectively diagnose or treat medical problems such as traumatic injuries and life-altering diseases over multiple time domains and biological systems. The most significant items to consider when constructing synthetic chemicals and structures are, first, the association kinetics and thermodynamics between cell and material after assembly, and, second, the modular nature of engineered materials that will trigger cellular activities such as receptor binding, endocytosis, membrane trafficking, regulated transcription and translation processes. Two different classes of synthetic materials that show different bioactivities have been interfaced to human neural stem cells (hNSCs). Engineered peptide amphiphiles that self-assemble into fibrous micellar (high-aspect ratio) structures show a spectrum of responses from hNSCs based on concentration and surface engineering properties while porous particles and extended surfaces do not. Physicochemical and biological characterization of both materials interfaced to hNSCs will be presented and their utility in bridging physical and life sciences will be discussed.