The development of a facile and versatile strategy to endow surfaces with synergistically anti-inflammatory, antimicrobial, and anticoagulant functions is of particular significance for blood-contacting biomaterials and medical devices. In this work, we report a simple and environmentally friendly "one-pot" method inspired by byssal cuticle chemistry, namely, [Fe(dopa) 3 ] coordination chemistry for assembly of copper ions (Cu 2+ ) and plant polyphenol (tannic acid)/ catecholamine (dopamine or norepinephrine) to form metal− phenolic/catecholamine network-based coatings. This one-pot method enabled us to easily develop a multifunctional surface based on the combination of the characteristic functions of metal ions and plant polyphenol or catecholamine. The residual phenolic hydroxyl groups on the coatings imparted the modified surface with excellent antioxidant and anti-inflammatory functions. The robust chelation of copper ions to the metal− phenolic/catecholamine networks provided not only durable antibacterial property but also glutathione peroxidase like catalytic capability to continuously and controllably produce antithrombotic nitric oxide by catalyzing endogenous S-nitrothiol. The biological functions of such coatings could be well regulated by adjusting the ratios of the feed concentration of Cu 2+ ions to plant polyphenol or catecholamine. We envision that our simple, multifunctional, and bioinspired coating strategy can hold great application promise for bioengineering blood-contacting devices.

The process of full-thickness skin regeneration is complex and has many parameters involved, which makes it difficult to use a single dressing to meet the various requirements of the complete regeneration at the same time. Therefore, developing hydrogel dressings with multifunction, including tunable rheological properties and aperture, hemostatic, antibacterial and super cytocompatibility, is a desirable candidate in wound healing. In this study, a series of complex hydrogels were developed via the hydrogen bond and covalent bond between chitosan (CS) and alginate (SA). These hydrogels exhibited suitable pore size and tunable rheological properties for cell adhesion. Chitosan endowed hemostatic, antibacterial properties and great cytocompatibility and thus solved two primary problems in the early stage of the wound healing process. Moreover, the sustained cytocompatibility of the hydrogels was further investigated after adding FGF and VE-cadherin via the co-culture of L929 and EC for 12 days. The confocal 3D fluorescent images showed that the cells were spherical and tended to form multicellular spheroids, which distributed in about 40–60 μm thick hydrogels. Furthermore, the hydrogel dressings significantly accelerate defected skin turn to normal skin with proper epithelial thickness and new blood vessels and hair follicles through the histological analysis of in vivo wound healing. The findings mentioned above demonstrated that the CS/SA hydrogels with growth factors have great potential as multifunctional hydrogel dressings for full-thickness skin regeneration incorporated with hemostatic, antibacterial, sustained cytocompatibility for 3D cell culture and normal skin repairing.

In situ endothelialization, aiming to create implantation surfaces capable of self-endothelialization, seems to be an extremely promising solution, particularly on those blood-contacting surfaces. In this research study, we immobilized the soluble semaphorin 4D (SEMA4D) and C-X-C motif chemokine ligand 12 (CXCL12) biomolecules together with heparin onto the metal-based biomaterial surfaces to achieve in situ endothelialization of modified samples both by stimulating the neighboring endothelial cells (ECs) migration and by capturing the circulating endothelial progenitor cells (EPCs) directly from the blood circulation. X-ray photoelectron spectroscopy data demonstrate the successful immobilization of SEMA4D and CXCL12. Due to the presence of heparin, hemocompatibility was also improved after modification. Although EC migration was mainly mediated by SEMA4D with the coordination of CXCL12, EC proliferation and haptotaxis property were also enhanced, while EC chemotaxis was slightly suppressed because the further immobilization of CXCL12 influences the release of SEMA4D. The results of the ex vivo EPC capturing assay indicated the mobilization of CXCL12 promotes EPC adhesion. In vivo implantation further demonstrated that CXCL12 cooperates with SEMA4D to promote a process of in situ endothelialization.

No abstract

No abstract