Cell migration plays a key role in normal biological processes such as developmental patterning, wound healing and immune response. Meanwhile, mutations that enable aberrant cell migration underpin the development of pathologies such as cancer metastasis. In addition, manipulating cell migration is a key design consideration in medical technologies that involve colonization of biomaterial implants. The modular construction of natural extracellular matrix proteins motivates the design of synthetic biomaterials presenting multiple epitopes that synergistically promote cell migration. While epitopes such as the RGD-containing, central cell-binding domain (CCBD) of fibronectin (FN) effectively mediate cell adhesion, complementing domains within FN such as the heparin-binding domain (HBD) significantly enhance CCBD-mediated cell spreading, membrane extension activity, focal adhesion (FA) formation and focal adhesion kinase (FAK) phosphorylation. Since these biophysical and biochemical events are integral elements of cell migration, we hypothesize that manipulating the surface density of CCBD and HBD on a biomaterial may be an effective method to tune cell migration speed. Importantly, because cell migration involves complex coordination of these intermediate processes, it is unclear whether concomitant enhancements in spreading, membrane extension activity, FA formation and biochemical signaling correlate monotonically to enhanced cell migration. Thus, the overall objective of the proposed work is to elucidate the quantitative synergy between CCBD and HBD in promoting cell migration, as outlined by the following Specific Aims: (1) to engineer a novel substratum for co-presenting CCBD and HBD in well-characterized, adjustable absolute and relative amounts, and (2) to quantify the dependence of cell migration speed on CCBD and HBD. Results from the proposed work will offer strategies for designing CCBD/HBD composite materials that promote cell migration for application in medical technologies involving colonization of biomaterials. ? ? ?
Galownia, Niki C; Kushiro, Keiichiro; Gong, Yuan et al. (2007) Selective desensitization of growth factor signaling by cell adhesion to fibronectin. J Biol Chem 282:21758-66 |