Endothelial Progenitor Cell Capture Research Articles

Functionalized CD133 antibody coated stent surface simultaneously promotes EPCs adhesion and inhibits smooth muscle cell proliferation-A novel approach to prevent in-stent restenosis.

We report a multistep strategy of biochemical surface modifications that resulted in the synthesis of new, effective and biocompatible intravascular implants coating with immobilized anti-CD133 antibodies, that proved to be the most effective in endothelial progenitor cells capture and reduced smooth muscle cells growth. Biomolecules were immobilized on differently functionalized surfaces. The distribution, nanostructural characteristics and intramolecular interactions of anti-CD133 molecules as well as their ability to bind EPCs was evaluated. We also tempted to build a molecular model of the CD133 protein to study antigen-antibody interactions. CD133 protein is expressed in endothelial progenitor cells (EPCs). Absence of preferential interaction site on CD133, but rather a presence of a small binding area, may be the specificity of reconnaissance sequence, thus importantly increasing the probability of CD133 protein binding. After all, regarding our molecular model, we are convinced that specific, and large enough interactions between anti-CD133 coating stent surface and CD133 present on EPCs will reduce risk of restenosis by favoring the endothelial growth. Additionally, the safety study of the vivo performance of modified titania based surface was performed using small animal models. No allergological or toxical local or systemic adverse effects of the developed coatings were noted.

Covalent immobilization of fibroblast-derived matrix on metallic stent for expeditious re-endothelialization

Here, we demonstrate a fibroblast-derived extracellular matrix (FDM) immobilized cobalt-chromium (Co–Cr) alloy surface to accelerate re-endothelialization. The surface characterization results showed that FDM molecules with their protein components such as collagen I, fibronectin, and laminin, were covalently grafted to Co–Cr surface. The in vitro cells experiments exhibited the superiority of the FDM-immobilized surface to capture and proliferate of endothelial progenitor and human umbilical cord vein endothelial cells than control Co–Cr alloy. These results suggested that the immobilization of FDM on the stent surface by this facile procedure could be an efficient and promising strategy to get expeditious re-endothelialization.

Clinical Outcomes One Year and Beyond After Combination Sirolimus-Eluting Endothelial Progenitor Cell Capture Stenting During Primary Percutaneous Coronary Intervention in ST-Segment Elevation Myocardial Infarction.

Primary percutaneous coronary intervention (PCI) during acute ST-segment elevation myocardial infarction (STEMI) represents a thrombotic milieu and is associated with delayed healing after stenting. The pro-healing combination sirolimus eluting endothelial progenitor cell (EPC) capture stents encourage early endothelialization after stenting and may be beneficial in the STEMI population. We aim to evaluate the clinical outcomes one year and beyond for patients with STEMI who received the combination sirolimus eluting EPC capture stents during primary PCI. All STEMI patients implanted with combination sirolimus eluting EPC capture stents during primary PCI from November 2013 to December 2016 were enrolled. The primary outcome was target lesion failure (TLF) at in-hospital, one-month, one-year and beyond one year. A total of 260 consecutive STEMI patients (283 lesions) were implanted with 313 combination sirolimus eluting EPC capture stents during primary PCI. Mean age was 56.1 ± 11.2 years and 88.8% were male. One in ten patients (10.9%) had cardiogenic shock on presentation, 7.3% needed mechanical ventilation and 7.7% had intra-aortic balloon pump inserted. A total of 97.9% of lesions achieve final TIMI 3 flow. Device success was seen in all patients. At extended follow up period (median 23.4 months), the clinical outcomes were TLF 8.8%, major adverse cardiovascular events 10.8%, cardiac mortality 4.2%, target vessel myocardial infarction 3.4%, target lesion revascularization 3.8%, and definite stent thrombosis 1.9%. This study demonstrated acceptable clinical outcomes for an all-comers STEMI patients undergoing primary PCI with the use of combination sirolimus eluting EPC cell capture stents.

The dual-therapy COMBO stent: a rationale for a light dual antiplatelet therapy treatment.

The COMBO stent is a new, sirolimus-eluting bioresorbable polymer, bioengineered stent. This technology combines the advantages of second-generation drug-eluting stents with the endothelial progenitor cell capture technology mediated by the anti-CD34 antibody coating on the COMBO luminal surface. This dual technology should improve vessel endothelium regeneration and may lay the biological basis for a short dual antiplatelet therapy course. As new evidence is adding on the safety and efficacy of this stent compared with first- and second-generation drug-eluting stents and across a variety of patient populations, aim of this review is to summarize available clinical experience and future perspective with this device.

9-year clinical follow-up of patients with ST-segment elevation myocardial infarction with Genous or TAXUS Liberté stents

ObjectivesThis matched-cohort retrospective study investigated the long-term (9-year) safety and efficacy outcomes of patients with ST-segment elevation myocardial infarction (STEMI) and primary percutaneous coronary intervention (pPCI) with Genous (n = 102) versus TAXUS Liberté (n = 101) stents in 2006–2008.BackgroundIn the era of off-label use of drug-eluting stents for pPCI in patients with STEMI, the use of first-generation Genous stents (endothelial progenitor cell capture stents that have a passive coating and accelerate re-endothelialization) was proposed.MethodsThe primary endpoint was 9-year major adverse cardiac and cerebrovascular events (MACCE), including all-cause death, re-infarction, target vessel revascularization (TVR), and stroke. The secondary endpoints were the separate primary endpoint events at pre-defined time-points (in-hospital, 6 months, and yearly) and stent thrombosis. Time-dependent 9-year composite MACCE, all-cause death, and TVR were compared using Kaplan-Meier estimates and multivariate Cox regression models.ResultsPropensity score analysis confirmed the comparability of the groups. Patients in the Genous and TAXUS groups had 7 and 1 acute definitive stent thrombosis events, respectively (p<0.001). There was a trend towards higher in-hospital MACCE in the Genous group (10.8%) versus the TAXUS group (4.0%). Kaplan-Meier analysis showed that 9-year MACCE was significantly worse in the Genous than in the TAXUS group. The in-hospital, 6-month, 1-year, and 9-year mortality rates were 7.8%, 8.8%, 9.8%, and 23.5% in the Genous group and 2.0%, 3.0%, 4.0%, and 16.8% in the TAXUS group.ConclusionsHigher peri-procedural, in-hospital, and short-term mortality led to worse outcomes for first-generation Genous stents versus TAXUS Liberté stents for pPCI in STEMI. TAXUS Liberté stents had more favorable 9-year clinical outcomes.

Japan-United States of America Harmonized Assessment by Randomized Multicentre Study of OrbusNEich's Combo StEnt (Japan-USA HARMONEE) study: primary results of the pivotal registration study of combined endothelial progenitor cell capture and drug-eluting stent in patients with ischaemic coronary disease and non-ST-elevation acute coronary syndrome.

AimsHarmonized Assessment by Randomized Multicentre Study of OrbusNEich’s Combo StEnt (HARMONEE) (NCT02073565) was a randomized pivotal registration trial of the Combo stent, which combined sirolimus and an abluminal bioabsorbable polymer with a novel endoluminal anti-CD34+ antibody coating designed to capture endothelial progenitor cells (EPC) and promote percutaneous coronary intervention (PCI) site healing.Methods and resultsClinically stabilized PCI subjects were randomized 1:1 to receive Combo or everolimus-eluting stents (EES). Between February 2014 and June 2016, 572 subjects with 675 coronary lesions underwent 1-year angiography and fractional flow reserve, with optical coherence tomography (OCT) in the first 140 patients. The primary clinical endpoint was non-inferior 1-year target vessel failure (TVF). The primary mechanistic endpoint of EPC capture activity was superior strut coverage by OCT. Target vessel failure occurred in 7.0% Combo (20/287) vs. 4.2% EES (12/285), a 2.8% [95% confidence interval (95% CI) −1.0%, 6.5%] difference, meeting the non-inferiority hypothesis (P = 0.02). There were no cardiac deaths, with one stent thrombosis observed in the EES group. Quantitative coronary angiography late loss with Combo was equivalent to EES. Optical coherence tomography strut coverage at 1 year was superior with Combo vs. EES [91.3% (95% CI 88.7%, 93.8%) vs. 74.8% (95% CI 70.0%, 79.6%), P < 0.001], with homogeneous tissue in 81.2% vs. 68.8%, respectively.ConclusionCombo stent demonstrated non-inferior 1-year TVF and late loss in a randomized comparison to EES, with superior strut-based tissue coverage by OCT as a surrogate of EPC capture technology activity.

Mussel adhesive protein fused with VE-cadherin domain specifically triggers endothelial cell adhesion.

Endothelium is the only known completely non-thrombogenic material. In the present study, a strategy to mimic the adhesive interactions of endothelial cells (ECs) to alter the vascular microenvironment was established and applied to directing the behaviour of cells. To facilitate the regeneration of a functional endothelium in vascular lesions, we designed a recombinant mussel foot protein (Mfp-5) fused with the VE-cadherin extracellular domain EC1-2, termed VE-M. Surface coating analysis showed that recombinant VE-M successfully formed a coating on substrate materials with uniform nanorods, low roughness, and sufficient hydrophilicity. We then evaluated the effects of VE-M on the adhesion of ECs and the capture of endothelial progenitor cells (EPCs). The result demonstrated that VE-M efficiently promoted the adhesion of ECs and EPCs. The number of ECs and EPCs on VE-M was 5.5- and 1.8-fold higher, respectively, than that on bare 316L SS under static conditions, whereas there was no significant difference in the number of captured smooth muscle cells (SMCs) between VE-M and other substrates. In addition, the number of EPCs captured by VE-M was approximately four times higher than that captured by 316L SS under dynamic conditions. In particular, the result of the neutralization test indicated that VE-M specifically triggered ECs' adhesion via the interaction of VE-cadherin EC1-2. Further investigation showed that VE-M significantly increased the levels of endogenous VE-cadherin in HUVECs as well as the endothelial eNOS content, with little or no endothelial inflammation. Our results showed that VE-M could be a promising biomimetic modification for accelerating endothelialization and vascularization in tissue engineering.

Exosome-Modified Tissue Engineered Blood Vessel for Endothelial Progenitor Cell Capture and Targeted siRNA Delivery.

Instability and poor targeting causes the long-term patency of RNA-modified tissue engineering blood vessels (TEBVs) remaining unsatisfactory. RNA can be enriched in exosome and then delivered into targeted cells while whether exosome-modified TEBVs achieve RNA targeted delivery is unclear. Here, to promote the expression of klotho protein on the mesenchymal stem cell (MSC)-derived exosomes, klotho plasmids are first transfected into MSCs, and adenosine kinase (ADK) siRNA is then loaded into exosome (klotho/ADK siRNA-exosome) using electrotransfection. Flow chamber results show that klotho/ADK siRNA-exosome can effectively capture circulating endothelial progenitor cells (EPCs). Besides, the captured EPCs can endocytose this exosome, and then decompose it into klotho protein and ADK siRNA. Moreover, ADK siRNA promotes the paracrine of proangiogenic factors and adenosine from EPCs, which further facilitate proliferation and migration of endothelial cells. Based on polyethyleneimine-capped gold nanoparticles, exosome-modified TEBVs are constructed through layer-by-layer assembly. Animal experimental results show that klotho/ADK siRNA-exosome-modified TEBVs can maintain the patency up to one month, and good endothelialization is observed. In short, one exosome-modified TEBV is constructed, capture molecules on the surface of exosome capture the circulating EPCs, and the loaded RNA achieves its purpose of accurate treatment depending on the needs of patients.

One-Year Clinical Outcome of Sirolimus-Eluting Endothelial Progenitor Cell Capture Combination Stent Versus Polymer-Free Biolimus A9 Coated Stent

Background: The polymer/carrier-free Biolimus A9 drug-coated BioFreedom® stent (Biosensors, Europe) has been shown to be superior to bare-metal stent in patients at high risk for bleeding. The sirolimus-eluting endothelial progenitor cell capture Combo® stent (OrbusNeich Medical, Florida) has also been shown to be safe with 1 month DAPT. Both stents are useful in patients with high bleeding risk requiring short duration of DAPT and unknown compliance to DAPT. However, the efficacy of Combo® stent compared to BioFreedom® stent is unknown.

Clinical outcomes after percutaneous coronary intervention with the COMBO stent versus Resolute Integrity and PROMUS Element stents: a propensity-matched analysis.

The COMBO stent combines sirolimus elution with an endothelial progenitor cell-capturing layer to promote early endothelialisation. There has not been a head-to-head comparison of this novel device with any other currently used drug-eluting stent (DES). We sought to compare clinical outcome at two years after COMBO stent placement with the Resolute Integrity or PROMUS Element stent in an all-comers cohort. Patients from the REMEDEE registry (COMBO, n=1,000) were matched with patients from the DUTCH PEERS trial (PROMUS Element/Resolute Integrity, n=1,811). Propensity score matching on 13 baseline characteristics was applied to create two balanced cohorts of patients treated with COMBO versus PROMUS Element/Resolute Integrity. Propensity score matching yielded 771 patient pairs, representing all-comers patients, with a median age of 65 years, 27% female and more than 50% of patients presenting with acute coronary syndrome. Target lesion failure (TLF), a composite of cardiac death, target vessel MI and any target lesion revascularisation, at two-year follow-up was 7.9% in COMBO and 6.4% in PROMUS Element/Resolute Integrity, HR 1.24 (95% CI: 0.85-1.81), p=0.26. Definite stent thrombosis (ST) was not significantly different between groups (0.8% vs. 0.9%, p=0.79). In a propensity-matched analysis, the COMBO stent showed similar rates of TLF and ST at two-year follow-up compared to Resolute Integrity and PROMUS Element.

The effect of anti-CD133/fucoidan bio-coatings on hemocompatibility and EPC capture

Surface modification by immobilizing biomolecules has been widely proved to enhance biocompatibility of cardiovascular implanted devices. Here, we aimed at developing a multifunctional surface that not only provides good hemocompatibility but also functions well in capturing circulating endothelial progenitor cells (EPCs) in the blood flow to improve the surface endothelialization. In the present work, we preferred to chemically co-immobilize (Michael addition and Schiff base reaction) the anti-CD133 (EPC-specific antibody) and fucoidan (EPC-mobilization factor, which also contribute to better hemocompatibility) onto a polydopamine (PDA) film which is famous for its stability and endothelial cell (EC) compatibility. The quantality of anti-CD133 and other surface characterization (X-ray photoemission spectroscopy, atomic force microscopy and water contact angle measurement) demonstrated successful preparation of the CD133/fucoidan coating. The platelets adhesion/activation test suggested improved hemocompatibility of this bio-coating. The ex vivo experiment on New Zealand white rabbits showed that the anti-CD133/fucoidan coating had good ability on capture the circulating EPC. In addition, the quartz crystal microbalance-D indicated that the EPC behaviors, including adhesion, spreading and extracellular matrix re-molding, were related to the density of anti-CD133 in the coating. We hope this anti-CD133/fucoidan multi-functional coating may provide potential application on surface modification of cardiovascular biomaterials.

Endothelial and cardiac progenitor cells for cardiovascular repair: A controversial paradigm in cell therapy.

Stem cells have the potential to differentiate into cardiovascular cell lineages and to stimulate tissue regeneration in a paracrine/autocrine manner; thus, they have been extensively studied as candidate cell sources for cardiovascular regeneration. Several preclinical and clinical studies addressing the therapeutic potential of endothelial progenitor cells (EPCs) and cardiac progenitor cells (CPCs) in cardiovascular diseases have been performed. For instance, autologous EPC transplantation and EPC mobilization through pharmacological agents contributed to vascular repair and neovascularization in different animal models of limb ischemia and myocardial infarction. Also, CPC administration and in situ stimulation of resident CPCs have been shown to improve myocardial survival and function in experimental models of ischemic heart disease. However, clinical studies using EPC- and CPC-based therapeutic approaches have produced mixed results. In this regard, intracoronary, intra-myocardial or intramuscular injection of either bone marrow-derived or peripheral blood progenitor cells has improved pathological features of tissue ischemia in humans, despite modest or no clinical benefit has been observed in most cases. Also, the intriguing scientific background surrounding the potential clinical applications of EPC capture stenting is still waiting for a confirmatory proof. Moreover, clinical findings on the efficacy of CPC-based cell therapy in heart diseases are still very preliminary and based on small-size studies. Despite promising evidence, widespread clinical application of both EPCs and CPCs remains delayed due to several unresolved issues. The present review provides a summary of the different applications of EPCs and CPCs for cardiovascular cell therapy and underlies their advantages and limitations.

Heparin/DNA aptamer co-assembled multifunctional catecholamine coating for EPC capture and improved hemocompatibility of vascular devices

Good hemocompatibility and rapid endothelialization are two key factors in the success of stent interventional therapy. In this study, aptamers with the ability to capture endothelial progenitors and anticoagulant molecular heparin were successfully immobilized on the surface of dopamine/polyethylenimine (PDA/PEI) copolymer coating via electrostatic interaction. The results of X-ray spectroscopy (XPS), water contact angle (WCA), and immunofluorescence staining tests confirmed the successful introduction of heparin and aptamers. Platelet adhesion and whole blood experiments demonstrated that the hemocompatibility of the co-modified surface was improved. Dynamic endothelial progenitor cell (EPC) capture experiments showed that the modified surfaces could effectively capture the endothelial progenitor in dynamic conditions. More importantly, ex vivo experiments revealed that the modified surfaces could regulate the distribution of CD34/vWF-positive cells on stent surfaces, and this was beneficial for the endothelialization of vascular stents. These results suggested that heparin and aptamer co-modified stents could capture EPCs and promote endothelialization. This surface co-modification strategy has great potential for enhancing stent development.

DEVELOPMENT OF A COMBINATORIAL MICROASSAY TO ENGINEER BIOMIMETIC VASCULAR SCAFFOLDS

Regeneration-promoting vascular substitutes such as pro-healing stents or vascular grafts could minimise the incidence of thrombosis, restenosis and other events leading to device failure. One strategy to promote endogenous repair mechanisms is to functionalise the surfaces of the vascular graft with peptides or proteins that capture circulating endothelial progenitor cells (EPCs). EPCs are circulating CD34+ bone marrow-derived cells that could have a significant impact on endothelialisation due to high proliferative and regenerative potential. Previous studies have tested surface-immobilised antibodies to capture EPCs, as well as surface-immobilised extracellular matrix-derived peptides to promote adhesion and expansion. However, these strategies have not been tested in combination. We hypothesise that the co-immobilisation of peptides and antibodies could maximise endothelialisation by targeting both the EPC capture and expansion steps.

Endothelial progenitor cell capture stents versus drug-eluting stents for angina or acute coronary syndrome

Reason for withdrawal from publication The Cochrane Heart Group withdrew this protocol as the current author team is unable to progress to the final review stage. The editors consider this title as low priority for the current portfolio of the Heart Group and therefore this title is not open to a new author team.

The effect of anti-CD34 antibody orientation control on endothelial progenitor cell capturing cardiovascular devices

Efficient immobilization of the antibody to the substrate is of crucial importance in the development of anti-CD34-based endothelial progenitor cells capturing cardiovascular devices. This should go along with precise control of the antibody orientation by appropriate immobilization technology for retaining antibody activity, like in immunosensors. Recently, great attention was paid to immobilization of anti-CD34 antibody onto substrates by covalent binding, but at random orientation. Here, to investigate the biological effect of antibody orientation, we have prepared two kinds of anti-CD34 antibody coated surfaces, with random immobilization and oriented immobilization. The immunological binding activity (IBA) of the antibody at oriented immobilization was 3.48 times higher than at random immobilization, indicating that the two different surfaces were successfully prepared. The endothelial progenitor cell-capturing capability of oriented antibody-immobilized surface was 1.35 and 1.64 times higher than for the random immobilized surface after seeding for 2 and 12 h under flow condition, respectively. The endothelial progenitor cell-capturing efficiency per antibody by oriented immobilization was 5.16 and 6.26 times higher than for the random after seeding for 2 and 12 h under flow condition, respectively. In addition, the oriented antibody-immobilized surface possessed better blood-compatibility. These results clearly revealed the significance of antibody orientation which could retain its biological effect and may revolutionize the antibody-immobilization protocols used in cardiovascular and other blood-contacting biomedical devices.

Disrupted Endothelial Cell Layer and Exposed Extracellular Matrix Proteins Promote Capture of Late Outgrowth Endothelial Progenitor Cells.

Late outgrowth endothelial progenitor cells (LO-EPC) possess a high proliferative potential, differentiate into vascular endothelial cells (EC), and form networks, suggesting they play a role in vascular repair. However, due to their scarcity in the circulation there is a requirement for ex vivo expansion before they could provide a practical cell therapy and it is currently unclear if they would home and engraft to an injury site. Using an in vitro flow system we studied LO-EPC under simulated injury conditions including EC activation, ischaemia, disrupted EC integrity, and exposed basement membrane. Perfused LO-EPC adhered to discontinuous EC paracellularly at junctional regions between adjacent cells under shear stress 0.7 dyn/cm2. The interaction was not adhesion molecule-dependent and not enhanced by EC activation. LO-EPC expressed high levels of the VE-Cadherin which may explain these findings. Ischaemia reperfusion injury decreased the interaction with LO-EPC due to cell retraction. LO-EPC interacted with exposed extracellular matrix (ECM) proteins, fibronectin and vitronectin. The interaction was mediated by integrins α5β3, αvβ1, and αvβ3. This study has demonstrated that an injured local environment presents sufficient adhesive signals to capture flow perfused LO-EPC in vitro and that LO-EPC have properties consistent with their potential role in vascular repair.

Construction of an Aptamer-SiRNA Chimera-Modified Tissue-Engineered Blood Vessel for Cell-Type-Specific Capture and Delivery.

The application of tissue-engineered blood vessels (TEBVs) is the main developmental direction of vascular replacement therapy. Due to few and/or dysfunctional endothelial progenitor cells (EPCs), it is difficult to successfully construct EPC capture TEBVs in diabetes. RNA has a potential application in cell protection and diabetes treatment, but poor specificity and low efficiency of RNA transfection in vivo limit the application of RNA. On the basis of an acellular vascular matrix, we propose an aptamer-siRNA chimera-modified TEBV that can maintain a satisfactory patency in diabetes. This TEBV consists of two parts, CD133-adenosine kinase (ADK) chimeras and a TEBV scaffold. Our results showed that CD133-ADK chimeras could selectively capture the CD133-positive cells in vivo, and then captured cells can internalize the bound chimeras to achieve RNA self-transfection. Subsequently, CD133-ADK chimeras were cut into ADK siRNA by a dicer, resulting in depletion of ADK. An ADK-deficient cell may act as a bioreactor that sustainably releases adenosine. To reduce nonspecific RNA transfection, we increased the proportion of HAuCl4 during the material preparation, through which the transfection capacity of polyethylenimine (PEI)/polyethylene glycol (PEG)-capped gold nanoparticles (PEI/PEG-AuNPs) was significantly decreased and the ability of TEBV to resist tensile and liquid shear stress was greatly enhanced. PEG and 2'-O-methyl modification was used to enhance the in vivo stability of RNA chimeras. At day 30 postgrafting, the patency rate of CD133-ADK chimera-modified TEBVs reached 90% in diabetic rats and good endothelialization was observed.

Adlayer-mediated antibody immobilization to stainless steel for potential application to endothelial progenitor cell capture.

This work describes the straightforward surface modification of 316L stainless steel with BTS, S-(11-trichlorosilylundecanyl)-benzenethiosulfonate, a thiol-reactive trichlorosilane cross-linker molecule designed to form intermediary coatings with subsequent biofunctionalization capability. The strategy is more specifically exemplified with the immobilization of intact antibodies and their Fab' fragments. Both surface derivatization steps are thoroughly characterized by means of X-ray photoelectron spectroscopy. The antigen binding capability of both types of biofunctionalized surfaces is subsequently assessed by fluorescence microscopy. It was determined that BTS adlayers achieve robust immobilization of both intact and fragmented antibodies, while preserving antigen binding activity. Another key finding was the observation that the Fab' fragment immobilization strategy would constitute a preferential option over that involving intact antibodies in the context of in vivo capture of endothelial progenitor cells in stent applications.

Can improvements in our physiological understanding yield information on the utility of endothelial progenitor cell capture stents?

intervention (PCI) patients. The index of myocardial resistance (IMR) was significantly lower in the latter than in the former group 6 to 12 months after index PCI. IMR can be used to diagnose microvascular dysfunction [4], which is known to be associated with an increased risk of adverse cardiovascular events [5]. Previous studies on the effects of DES implantation on en dothelial function have yielded mixed results. The effects of stent type on microvascular function have not been