Cell morphology has a profound effect on a range of cellular events, such as proliferation, differentiation, cytoskeletal organization, and presumably gene expression. One proposed mechanism for the transduction of cell shape information into gene expression is through mechanical forces transmitted via the direct link of the cytoskeleton to the nucleus, and in particular to nuclear matrix proteins (NMPs) such as NMP 1 and 2. Previously, we have developed methods for both controlling cell and nuclear shape on the micron length scale, and measuring in situ mRNA expression in an effort to help elaborate relationships that control cell fate. Although previous studies have employed surfaces with spatially resolved chemistry to study cell shape/function relationships and their effect on protein synthesis, in situ gene expression (mRNA) and protein synthesis as a function of the cell projected area and nuclear shape, these studies have been limited by the inability to independently control the input into the cell via cell surface contacts. This limitation has prevented the analysis of the effect of ligand type, density, and nanoscale distribution in controlling cell fate. To alleviate this problem, fabrication of more elaborate surfaces are necessary to design experiments that examine surface properties that control cell fate. In this proposal we attempt to circumvent the aforementioned limitation by creating surfaces that can control peptide ligand density and ligand nanoscale distribution to control the spatial arrangements of focal adhesion on a nanometer (nm) length scale. By controlling the cytoskeleton, we anticipate that we can independently control the cell's shape and the shape of its' nucleus. We will exploit a custom built NSOM laser to """"""""write"""""""" patterns of peptide ligands that subsequently engage with integrin receptors for precise control of focal adhesion locations on the nm length scale. These culture surfaces will have a number of conceivable applications in the fields of biotechnology, dentistry and medicine. First, because they will allow cell and nuclear shape to be controlled as an independent variable, they are invaluable as experimental platforms for the study of cell shape/gene expression hierarchies. Second, since these surfaces will enable the fundamental control of cell differentiation and proliferation, we ultimately hope to map the nanopatterning technique to the surface of biomaterials, such as dental implants to control cell behavior at the interface.
| Mathur, Anurag; Ma, Zhen; Loskill, Peter et al. (2016) In vitro cardiac tissue models: Current status and future prospects. Adv Drug Deliv Rev 96:203-13 |
| Jeon, Hojeong; Koo, Sangmo; Reese, Willie Mae et al. (2015) Directing cell migration and organization via nanocrater-patterned cell-repellent interfaces. Nat Mater 14:918-23 |
| Schmidt, Ray C; Healy, Kevin E (2013) Effect of avidin-like proteins and biotin modification on mesenchymal stem cell adhesion. Biomaterials 34:3758-62 |
| Keung, Albert J; Healy, Kevin E; Kumar, Sanjay et al. (2010) Biophysics and dynamics of natural and engineered stem cell microenvironments. Wiley Interdiscip Rev Syst Biol Med 2:49-64 |
