Engineering Device Surfaces That Instruct Cell Behavior
EMSL Project ID
3672
Abstract
The development of material interfaces that control cell behavior is a central challenge for the fields of diagnostics, drug screening, biomaterials, biosensors, and tissue engineering. The extracellular matrix of tissues plays an important role in instructing normal cell behavior, and the engineering of ?soft? material interfaces that mimic this environment could provide new routes to protecting cells on devices against apoptosis (programmed cell death), in stabilizing the phenotopye of cells over longer periods of time, in controlling the differentiation of cells to defined biological endpoints, and many other important cellular processes. These interfaces must promote specific receptor-mediated signaling pathways that lead to desirable biological effects, as well as minimize nonspecific interactions that lead to loss of control of cell behavior.We have recently discovered peptide sequences can be designed with cell interaction sequences to direct specific receptor-mediated signaling properties on either hydrophobic or polyelectrolyte surfaces. In this project, we will design and characterize these fusion peptides that assemble onto biomaterial surfaces and direct cell behavior. This approach should be generally applicable to a wide range of diagnostic, sensor, microfluidic, and implantable biomaterial surfaces. The design and characterization of peptide assembly on the material surfaces will be based on unique solid-state NMR capabilities that provide molecular structure and dynamics information. The functional activities of the peptides will be characterized with complementary gene chip and proteomics technologies to completely characterize the signaling pathway activation induced by the peptide coating.
The initial model peptide system will be directed toward the control of the MAPK signaling pathway in osteoblasts. We have recently characterized the activity of fusion peptides that combine the integrin-binding sequences GRGDS and DGEA and an anionic domain that directs peptide assembly on HAP and cationic polyelectrolyte surfaces. Both the GRGDS and DGEA engage focal adhesion kinase phosphorylation, but only the DGEA sequence directs the phosphorylation and activation of the MAPK marker ERK. This finding demonstrates that these fusion peptides can selectively engage specific receptor-mediated signaling pathways, and now we propose to do a full study of the signaling pathway activation by genomic and proteomic array techniques. These will be focused initially on the MAPK pathway and CbfA activation, which is connected to control of osteoblast differentiation and proliferation. Solid-state NMR techniques will be used to study how peptide sequence can be designed to optimize the structure and dynamics of the polyelectrolyte recognition domain, as well as the structure and dynamics of the cell interaction sequence.
We expect that these initial studies will provide the basis for a full proposal that is directed toward the design of peptide coatings that promote other desirable signaling pathway endpoints. We are particularly focused on engaging pathways associated with protection against apoptosis in the device environment and on cell-type specific pathways that preserve differentiated cell phenotypes. The initial studies are closely focused to develop the molecular characterization capabilities and the genomics/proteomics characterization capabilities that would enable a larger program. The cell biology, NMR and mass spectrometry-proteomics work encompassed in this proposal will be prepared for publication as work is completed and thoroughly analyzed. Potential peer reviewed journals include Science, Nature, Biochemistry, J. of the American Chemical Society and other high visibility journals.
Project Details
Project type
Exploratory Research
Start Date
2003-08-07
End Date
2005-08-22
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members