Layer-by-layer biofabrication of coronary covered stents with clickable elastin-like recombinamers

Abstract

Coronary artery disease is the leading cause of death around the world. Endovascular stenting is the preferred treatment option to restore blood flow in the coronary arteries due to the lower perioperative morbidity when compared with more invasive treatment options. However, stent failure is still a major clinical problem, and further technological solutions are required to improve the performance of current stents. Here, we developed coronary stents covered with elastin-like recombinamers (ELRs) by exploiting a layer-by-layer technique combined with catalyst free click-chemistry. The resulting ELR-covered stents were intact after an in vitro simulated implantation procedure by balloon dilatation, which evidence the elastic performance of the membrane. Additionally, the stents were mechanically stable under high flow conditions, which is in agreement with the covalent and stable nature of the click-chemistry crosslinking strategy exploited during the ELR-membrane manufacturing and the successful embedding of the stent. Minimal platelet adhesion was detected after blood exposure in a Chandler loop as shown by scanning electron microscopy. The seeding of human endothelial progenitor cells (EPCs) on the ELR-membranes resulted in a confluent endothelial layer. These results prove the potential of this strategy to develop an advanced generation of coronary stents, with a stable and bioactive elastin-like membrane to exclude the atherosclerotic plaque from the blood stream or to seal coronary perforations and aneurysms, while providing a non-thrombogenic luminal surface and favouring the endothelialization.

Biohybrid elastin-like venous valve with potential for in situ tissue engineering

“…Images were taken from randomly chosen areas, which were representative of the entire sample. This behavior is correlated with the RGD cell adhesion motifs present in the ELR, which provide suitable anchor points for cell attachment and proliferation, as previously reported in in vitro experiments, in which HUVEC adhesion occurred only after 2 h (Fernández-Colino et al, 2019b, 2019aGonzález-Pérez F. et al, 2021). The alternative version of the EVV also showed a minimal amount of platelet adhesion, with a covered area of only 1.0 ± 0.2%, which contrast with the behavior of GORE-TEX ® (56.1 ± 3.1% covered area) and fibrin (full covered area 98.8 ± 0.6%) and hemolysis value of 0.06 ± 0.11%.…”

“…ELRs can be chemically decorated with catalyst-free click cross-linkable groups to guide the formation of stable hydrogels under mild physiological conditions through the strain-promoted [3 + 2] azide-alkyne cycloaddition (SPAAC) ( Kolb et al, 2001 ). This technology has been exploited for the fabrication of ELR hydrogels with excellent properties for cardiovascular applications (e.g., vascular grafts ( Fernández-Colino et al, 2019b ; González-Pérez M. et al, 2021 ), coronary covered stents ( de Torre et al, 2015 ; Fernández-Colino et al, 2019a ), and more recently heart valves ( Saidy et al, 2022 ), thus proving themselves as a very promising material for in situ TE.…”

Combining tunable proteolytic sequences and a VEGF-mimetic peptide for the spatiotemporal control of angiogenesis within Elastin-Like Recombinamer scaffolds

“…This technique has reported the formation of biocompatible ELR hydrogels [20] that promoted the regeneration of different tissues, thanks to their bioinspired ECM-like nature and to the inclusion of bioactive sequences [21]. For instance, they have shown to enable the regeneration of bone [22], cartilage [23,24], skeletal muscle [25], cornea [26] and cardiovascular tissues [27][28][29]. In addition, ELRs have demonstrated a non-immunogenic response, promoting the shift from type-1 macrophages (M1, pro-inflammatory) towards type-2 macrophages (M2, pro-regenerative), thus preventing fibrosis and inducing an improved healing of the damaged tissue [25].…”

Elastin-like recombinamer-based devices releasing Kv1.3 blockers for the prevention of intimal hyperplasia: An in vitro and in vivo study

“…Solutions of VKV-CO and IK-N3 were prepared in ultrapurified water at 100 mg/ml and kept at 4°C for at least 24 h. In PAP-1 loaded gels, the necessary quantity of 26 mM of PAP-1 in DMSO will be added to both solutions to get a final concentration of 1mM. 1) Covered grids (Square 50 Mesh Tabbed Grids Nickel, Agar Scientific AGG2905N) used as mimetic DES [19] were obtained by dip-coating alternating the solutions of IK-N3 and VKV-CO, kept at 4°C in two separate containers, sequentially immersing the device first in the solution with IK-N3 and then in the VKV-CO solution [19]. This step was repeated 10 times with 5 min gaps between each layer to allow the cross-linking of the azide and the cyclooctine groups of adjacent layers, and macroscopically assessed with a Leica DMS 1000 digital microscope system (Figure 1 A, B).…”

“…Moreover, these tailored polymers exhibit great biocompatibility, mechanical properties similar to those of natural elastin, self-assembly capability and a fully reversible thermosensitive behavior. ELRs catalyst-free click hydrogels can be produced under physiological conditions, and are attractive candidates for the fabrication of coated vascular stents by injection molding [17,18] or layer-by-layer dip-coating techniques [19], with good durability, as previously demonstrated in an ELR coated angioplasty balloon [20]. These coatings represent a good strategy for the development of a next generation of DES, and in fact drug loaded ELRs have been used as advanced delivery systems with promising results in diseases such as rheumatoid arthritis [21], cancer [22] or ischemia [23], showing also versatility in the embedded drug to release.…”