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[Display omitted] Despite advances in stent technologies, restenosis remains a serious problem of interventional cardiology and is considered as a consequence of the progressing inflammation within the vessel wall. Thus, attempts to extinguish this inflammatory process undoubtedly motivate the development of a coating that exhibits immunomodulatory properties. Hence, we propose a polydopamine-based-coating functionalized with an anti-inflammatory interleukin is reported. By the ATR-FTIR spectroscopy and AFM examination the incorporation of cytokines into the coating structure is confirmed, thus effective functionalization is proved. The gradual delivery of cytokines allows to limit the influence of IL-4 and IL-10 deficiency, which is recognized as a restenosis risk factor. A relatively steady cytokine release profile exhibits therapeutic potential in the first days after implantation and in preventing late complications on cellular model. In vitro coating studies prove the promotion of endothelialization in the initial stage after implantation, being consistent with present treatment strategies. The limitation of IL-8 and MCP-1 daily release by coating-interacted-endothelium significantly reduce another risk factor of restenosis. Finally, by assessing the changes in THP-1 differentiation, the coating immunological activity is confirmed, so the binding procedure do not impair biological properties of the interleukin. Therefore, it can be concluded that proposed anti-inflammatory coating can reduce the probability of restenosis to a minimum. [ABSTRACT FROM AUTHOR]

In this study we present the porous silica-based material that can be used for in situ drug delivery, offering effective supply of active compounds regardless its water solubility. To demonstrate usability of this new material, three silica-based materials with different pore size distribution as a matrix for doping with Photolon (Ph) and Protoporphyrin IX (PPIX) photosensitizers, were prepared. These matrices can be used for coating cardiovascular stents used for treatment of the coronary artery disease and enable intravascular photodynamic therapy (PDT), which can modulate the vascular response to injury caused by stent implantation—procedure that should be thought as an alternative for drug eluting stent. The FTIR spectroscopic analysis confirmed that all studied matrices have been successfully functionalized with the target photosensitizers. Atomic force microscopy revealed that resulting photoactive matrices were very smooth, which can limit the implantation damage and reduce the risk of restenosis. No viability loss of human peripheral blood lymphocytes and no erythrocyte hemolysis upon prolonged incubations on matrices indicated good biocompatibility of designed materials. The suitability of photoactive surfaces for PDT was tested in two cell lines relevant to stent implantation: vascular endothelial cells (HUVECs) and vascular smooth muscle cells (VSMC). It was demonstrated that 2 h incubation on the silica matrices was sufficient for uptake of the encapsulated photosensitizers. Moreover, the amount of the absorbed photosensitizer was sufficient for induction of a phototoxic reaction as shown by a rise of the reactive oxygen species in photosensitized VSMC. On the other hand, limited reactive oxygen species (ROS) induction in HUVECs in our experimental set up suggests that the proposed method of PDT may be less harmful for the endothelial cells and may decrease a risk of the restenosis. Presented data clearly demonstrate that porous silica-based matrices are capable of in situ delivery of photosensitizer for PDT of VSMC. [ABSTRACT FROM AUTHOR]