In vitro and in vivo cytocompatibility evaluation of biodegradable magnesium-based stents: a review

Biodegradable magnesium (Mg)-based vascular stents have been designed as temporary scaffolds to treat angiostenotic lesions for the maintenance of normal blood flow. Numerous studies have presented in vitro and in vivo tests for the evaluation of the safety and feasibility of Mg-based vascular stents and the related materials. Therein the cyto-compatibility is a basic and important parameter in the evaluation system. In this review, we summarize the applications and limitations of in vitro evaluation methods including basic characterization methods and direct and indirect cytotoxicity tests. We discuss the influencing factors on cytotoxicity, such as surface roughness, preconditioning of sample surface, cell type for the biocompatibility evaluation in direct contact as well as conditions for the formation of extracts/degradation products for indirect assays. Besides, we highlight the recent in vivo animal tests and clinical trials about Mg-based stents along with some associated results. The aim of this review is to provide a meaningful reference in the further developments and related evaluation methods of Mg-based stents.