Bio-manufacturing Biomimrtic Layer Of Smooth Muscle And Endothrlial Extracellular Matrix On Titanium Surface And Its Biocompatibility

A variety of biomedical metals devices have been widely used in the treatment of cardiovascular implants,such as artificial heart valves,ventricular pumps,and vascular stents.Although great effects have been put into rigorous anticoagulation,late thrombosis still occurred due to inferior blood and cell compatibility.Natural endothelium is popularly regarded as the only substance that has long-term anticoagulant ability to maintain normal vascular patency.So,establishment of a compact endothelial cell?EC?monolayer on cardiovascular implants?CVIs?surface is a guarantee for their long-term potency.In previous studies,it has been demonstrated that the native extracellular matrix?ECM?directly secreted by human umbilical vein endothelial cells?HUVECs?of titanium?Ti?CVIs,and also compare the ECM deposition by smooth muscle cell?SMCs?,using two types of natural ECM for Ti CVIs modification can simultaneously improve their in vitro blood compatibility and cytocompatibility.However,results demonstrated that the ECs-ECM,SMCs-ECM differed considerably in components and fibril morphology,the construction of ECs-ECM or SMCs-ECM alone on the surface of the implant may result in loss of function.Therefore,in this paper,surface modification of Ti CVIs with stripe-like HA?HAP?and both types of natural ECM was effective in improving their in vitro hemocompatibility and cytocompatibility simultaneously.First,HAP biomimetic regulation of SMCs phenotypic contraction and secretion of more ECM.After removing SMCs,ECs were regulated to secrete more ECM,and ECs were removed.A HA micropattern composite SMCs-ECM/ECs-ECM biomimetic layer was constructed on the surface of the material.The surface biochemical modification used biomacromolecular micropattern by soft lithography and sequential culture/desorption of two cells to achieve functional bionics on the titanium surface.In this paper,the surface of the HAP composite SMCs-ECM/ECs-ECM biomimetic layer modified material was constructed on the surface of the material by soft lithography and decellularization.The surface structure,stability,morphology,hydrophobicity and composition of the biomimetic layer were characterized by optical microscopy,scanning electron microscopy?SEM?,fourier transform attenuated total reflection?ATR-FTIR?,atomic force microscopy?AFM?and water contact angle?WCA?,the presence and content of the main components of the biomimetic layer were analyzed by immunofluorescence and immunohistochemistry.The difference in cell types is also different for the amount of extracellular matrix secreted.The constructed biomimetic layer ECM_SMC/EC/HAP can promote the adhesion,proliferation and migration of endothelial cells,inhibit the adhesion of smooth muscle cells,effectively regulate the contraction of smooth muscle phenotype,and regulate the immunophenotype of macrophages?anti-inflammatory phenotype,M2?,long-term implanted with a friendly histological response,the construction of this biomimetic surface will not cause hemolysis of the sample,and can reduce the adhesion and activation of platelets on the surface of the material,which can improve the blood compatibility of the surface of the material and It has a better tissue repair and inflammation regulation when implanted in vivo.In summary,the construction of HA micropattern composite SMCs-ECM/ECs-ECM biomimetic layer on the surface of NaOH-treated titanium can promote the growth and migration of ECs,inhibit the adhesion of SMCs,and regulate the phenotypic contraction of SMCs,with good blood compatibility and tissue compatibility,promote endothelial tissue repair,has important research value and guiding significance for surface functionalization modification of cardiovascular implants.This paper proposes a surface modification strategy that may have both anti-inflammatory and anti-coagulation at the same time,and promote the rapid endothelialization of the surface of the material in the later stage,which can provide a new idea for the development of the surface of new cardiovascular implant devices.