Distinctive effects of CD34- and CD133-specific antibody-coated stents on re-endothelialization and in-stent restenosis at the early phase of vascular injury

It is not clear what effects of CD34-and CD133-specific antibody-coated stents have on reendothelialization and in-stent restenosis(ISR)at the early phase of vascular injury.This study aims at determining the capabilities of different coatings on stents(e.g.gelatin,anti-CD133 and anti-CD34 antibodies)to promote adhesion and proliferation of endothelial progenitor cells(EPCs).The in vitro study revealed that the adhesion force enabled the EPCs coated on glass slides to withstand flow-induced shear stress,so that allowing for the growth of the cells on the slides for 48 h.The in vivo experiment using a rabbit model in which the coated stents with different substrates were implanted showed that anti-CD34 and anti-CD133 antibody-coated stents markedly reduced the intima area and restenosis than bare mental stents(BMS)and gelatin-coated stents.Compared with the anti-CD34 antibody-coated stents,the time of cells adhesion was longer and earlier present in the anti-CD133 antibody-coated stents and anti-CD133 antibody-coated stents have superiority in re-endothelialization and inhibition of ISR.In conclusion,this study demonstrated that anti-CD133 antibody as a stent coating for capturing EPCs is better than anti-CD34 antibody in promoting endothelialization and reducing ISR.

Recent advances in cardiovascular stent for treatment of in-stent restenosis:Mechanisms and strategies

Treatments of atherogenesis,one of the most common cardiovascular diseases(CVD),are continuously being made thanks to innovation and an increasingly in-depth knowledge of percutaneous transluminal coronary angioplasty(PTCA),the most revolutionary medical procedure used for vascular restoration.Combined with an expanding balloon,vascular stents used at stricture sites enable the long-time restoration of vascular permeability.However,complication after stenting,in-stent restenosis(ISR),hinders the advancement of vascular stents and are associated with high medical costs for patients for decades years.Thus,the development of a high biocompatibility stent with improved safety and efficiency is urgently needed.This review provides an overview of current advances and potential technologies for the modification of stents for better treatment and prevention of ISR.In particular,the mechanisms of in-stent restenosis are investigated and summarized with the aim to comprehensively understanding the pathogenesis of stent complications.Then,according to different therapeutic functions,the current stent modification strategies are reviewed,including polymeric drug eluting stents,biological friendly stents,prohealing stents,and gene stents.Finally,the review provides an outlook of the challenges in the design of stents with optimal properties.Therefore,this review is a valuable and practical guideline for the development of cardiovascular stents.

A TEMPOL and rapamycin loaded nanofiber-covered stent favors endothelialization and mitigates neointimal hyperplasia and local inflammation

An increased level of reactive oxygen species(ROS)plays a major role in endothelial dysfunction and vascular smooth muscle cell(VSMC)proliferation during in-stent thrombosis and restenosis after coronary artery stenting.Herein,we report an electrospun core-shell nanofiber coloaded with 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl(TEMPOL)and rapamycin(RAPA)that correspondingly serves as an ROS scavenger and VSMC inhibitor.This system has the potential to improve the biocompatibility of current drug-eluting stent(DES)coatings with the long-term and continuous release of TEMPOL and rapamycin.Moreover,the RAPA/TEMPOL-loaded membrane selectively inhibited the proliferation of VSMCs while sparing endothelial cells(ECs).This membrane demonstrated superior ROS-scavenging,anti-inflammatory and antithrombogenic effects in ECs.In addition,the membrane could maintain the contractile phenotype and mitigate platelet-derived growth factor BB(PDGF-BB)-induced proliferation of VSMCs.In vivo results further revealed that the RAPA/TEMPOL-loaded covered stents promoted rapid restoration of vascular endothelium compared with DES and persistently impeded inflammation and neointimal hyperplasia in porcine models.