Stealth functionalization of biomaterials and nanoparticles by CD47 mimicry

Polymeric biomaterials and nanoparticles (NPs) have shown a potential to be widely used for medical purposes. Functional limits of their biocompatibility depend on cellular and molecular responses between host and their artificial surfaces. Accordingly, medical devices of polymer biomaterials like endovascular stents, cardiopulmonary bypass circuits, and prostheses, may trigger inflammation or can be rejected by host due to the induction of immune responses. Furthermore, the main restriction to the use of NPs for medical purposes is their short in vivo circulation time because of their rapid clearance via the reticuloendothelial system. Various methods are under investigation to produce bioinert biomaterials and NPs. Currently, PEGylation and camouflaging are the most common approaches to enhance their biocompatibility. However, the disadvantages and limitations of these methods are leading to research new strategies. The CD47 molecule is well known as a widely expressed cellular surface receptor activating the transudction of the ''don't-eat-me'' signal. This review elaborates on the role of CD47 in the immune system and the application of CD47 mimicry peptides to produce bioinert biomaterials and NPs.