Cardiovascular biomaterials: when the inflammatory response helps to efficiently restore tissue functionality?

The evaluation of biological host response to implanted materials permits the determination of the safety and biocompatibility of biomedical devices, prostheses and biomaterials. Once a biomaterial is introduced into the body to a corresponding implant site, a sequence of events occurs promoting the activation of inflammatory mediators such as leukocytes and the release of signaling molecules such as cytokines and growth factors, evoking an inflammatory and wound healing process. This review examines the cellular and molecular mechanisms involved in the foreign body reaction, especially how cytokines impact the overall inflammatory response to devices. It also reviews how these events can be modulated by the physical and chemical properties of the biomaterials such as wettability, chemistry and geometry of surface. Particular attention is dedicated to the cardiovascular field, where the use of synthetic polymers has several limitations such as thrombogenicity and risk of infection. New materials and strategies to improve biomaterial characteristics are discussed.