Researchers) TERAMURA Yuji, Attached to Research Group, Applied Molecular Function Research Group, Cellular and Molecular Biotechnology Research Institute
A researcher in AIST, in collaboration with the Japan Medical Startup Incubation Program (JMPR) and N.B. Medical Corporation, has developed a novel anti-thrombogenic coating for stents used in the treatment of intracranial aneurysms.
In medical devices that come into contact with blood, the control of thrombus formation is an important factor in avoiding serious complications. Because of the placement of foreign bodies in blood vessels, patients with stents are always at risk for thrombotic complications. Therefore, antiplatelet medication is mandatory. Many antithrombotic coatings have been investigated to reduce the risk of thrombus formation. The principle of conventional coatings is that they exhibit antithrombotic properties by inhibiting nonspecific adsorption of plasma proteins. However, the inhibition of protein adsorption also means inhibition of cell adhesion. Therefore, although the antithrombogenicity is improved, the cell adhesiveness is accordingly decreased in conventional coating technology.
Recently, we have found an anti-thrombogenic coating with a new principle. This technology preferentially captures non-coagulant proteins in the blood, thereby inhibiting the blood coagulation reaction from the stent surface due to the blocking effect. This technology, which controls rather than inhibits the protein adsorption, provides anti-thrombogenic properties while simultaneously is able to improve the cell adhesion. The improved cell adhesion can accelerate the coverage of the stent with the vessel. The early coverage of the stent with the vessel means earlier completion of the stent therapy.
This technology reduces the occurrence of thrombotic complications, which have been an issue with stent therapy. Furthermore, it enables reduction of the treatment period, and thereby, the amount of antiplatelet drug use can be lower, which not only reduces the burden on patients, but also contributes to the medical cost cut.
The details of this technology were published in Scientific Reports on July 10, 2024.
In recent years, due to progress in medical equipment, minimally invasive endovascular treatment has become the mainstream in the treatment of intracranial aneurysms, the main cause of subarachnoid hemorrhage. In particular, coil embolization with a stent has been reported to be highly safe and effective, and is now considered one of the most established endovascular treatment methods. However, this technique carries the risk of vascular occlusion due to thrombus formation caused by the blood incompatibility with stent. Therefore, patients with stents must take antiplatelet drugs, however, thrombotic complications occur at a certain rate even when taking antiplatelet drugs, and the risk of bleeding complications increases while taking these drugs. Furthermore, the long-term use of these drugs increases the burden on patients and increases medical costs.
To solve these problems, many anti-thrombogenic polymer coatings have been investigated to provide anti-thrombogenic properties to the stent surface. However, while conventional polymers inhibit thrombus formation, they have the disadvantage of inhibiting the coverage of the stent with the vessel, known as endothelialization, which is associated with cell adhesion. In stent-based therapy, healing is complete when the stent undergoes complete endothelialization. However, if cells fail to adhere, the endothelialization hardly occurs, delaying stent coverage with the vessel, leading to the risk of delayed healing. This leads to a vicious cycle in which antiplatelet medication period is prolonged, further increasing the risk of bleeding complications. For this reason, there has long been a need in clinical setting for coating technologies that have antithrombotic properties with cell adhesion without inhibiting the endothelialization. However, these two properties are contradictory, and no coating materials with those two properties have been available.
Journal: Scientific Reports
Title: Stent coating containing a charged silane coupling agent that regulates protein adsorption to confer antithrombotic and cell-adhesion properties
Authors: Naoki Inuzuka, Yasuhiro Shobayashi, Satoshi Tateshima, Yuya Sato, Yoshio Ohba, Kristina N. Ekdahl, Bo Nilsson, and Yuji Teramura
DOI: https://doi.org/10.1038/s41598-024-65832-5