The Michigan Technological University team has been developing zinc alloys to serve as biodegradable arterial implant scaffolds. A big surprise in early reports has motivated the exploration of the effect of zinc degradation on the formation of intimal hyperplasia. A gradient of smooth muscle cells (SMCs) was discovered within the stable neointima surrounding the zinc arterial implants. A thin band of SMCs was present along the outer perimeter of the neointima, with no SMCs closer to the implant surface. The cell gradient and stability of the SMC layer strongly suggests a mechanism of active cell suppression, a possibility never explored in the scientific literature for metallic materials. Since reendothelialization is not inhibited, the suppressive activity appears specific to SMCs. Another discovery is that either modification of the surface finish or minor modifications of composition of Zn materials provoking a change in the degradation rate elicit dramatically varying SMC responses. Here, we intend to test the hypothesis that the rate of zinc degradation alters the flux of bioactive corrosion products towards vascular cells present within the neointima and that the rate of flux may regulate the degree of SMC suppression and neointimal character.
We are developing zinc alloys to serve as biodegradable arterial implant scaffolds. Here, we intend to test the hypothesis that the rate of zinc degradation alters the flux of bioactive corrosion products towards vascular cells present within the neointima and that the rate of flux may regulate the neointimal character.
