| AVS 55th International Symposium & Exhibition | |
| Biomaterial Interfaces | Tuesday Sessions |
| Session BI-TuM |
| Session: | Protein and Cell Interactions at Interfaces |
| Presenter: | E. Hanley, University of Wisconsin-Madison |
| Authors: | E. Hanley, University of Wisconsin-Madison J.L. Lauer, University of Wisconsin-Madison G.E. Lyons, University of Wisconsin-Madison J.L. Shohet, University of Wisconsin-Madison |
| Correspondent: | Click to Email |
Plasma polymerized tetraglyme coatings have been studied for their non-fouling and biocompatibility properties due to their inhibition of non-specific protein binding. In this work, we explore how embryonic stem (ES) cell differentiation patterns are affected by surface interactions with various plasma-processed materials. In order to identify a surface as a potential scaffolding material for ES cells in the development of an artificial blood vessel, at least two design criteria must be met. First, the ES cells must adhere to the surface. Second, the surface must facilitate, rather than inhibit, the process of vasculogenesis. ES cells were plated on the following surfaces to compare their effectiveness: 1.) glass cover slips onto which a coating of tetraglyme was deposited by plasma polymerization, 2.) vacuum gas plasma treated polystyrene (Falcon), and 3.) unprocessed control glass coverslips (Corning). In order to characterize the progression of differentiation of the ES cells, each sample was fixed three and seven days after cells had been plated on each surface, and then stained for immunofluorescence analysis. Two genetic markers were used for the antibody staining procedure. PECAM (platelet endothelial cell adhesion molecule: CD31) is an early marker for endothelial cell differentiation. vWF (von Willebrand Factor) is a cytoplasmic protein only expressed in mature endothelial cells. It has been previously reported by using an RT-PCR/southern hybridization blot analysis that ES cells in embryoid bodies first express PECAM near day 5 of differentiation and will first express vWF near day 11 of differentiation. ES cells that were plated on tetraglyme surfaces showed expression of PECAM after 3 days and vWF after 7 days of being plated on the surface. The positive results seen by ES cell derivatives precociously expressing the vWF and PECAM genetic markers on the surfaces suggest a directed differentiation of ES cells into endothelial cells. Furthermore, by using confocal microscopy, it was shown that the endothelial cells that express the vWF genetic marker are those cells closest to the tetraglyme coating. We conclude that the nature of the surface does influence R1 stem cell differentiation. It has also been shown that higher mole fractions of tetraglyme in the plasma during processing increases the percentage of endothelial cell expression.