Bioreactivity of Stent Material: <i>In Vitro</i> Impact of New Twinning-Induced Plasticity Steel on Platelet Activation

Abstract

A current challenge concerns developing new bioresorbable stents that combine optimal mechanical properties and biodegradation rates with limited thrombogenicity. In this context, twinning-induced plasticity (TWIP) steels are good material candidates. In this work, the hemocompatibility of a new TWIP steel was studied in vitro via hemolysis and platelet activation assessments. Cobalt chromium (CoCr) L605 alloy, pure iron (Fe), and magnesium (Mg) WE43 alloy were similarly studied for comparison. No hemolysis was induced by TWIP steel, pure Fe, or L605 alloy. Moreover, L605 alloy did not affect CD62P exposure, αIIbβ3 activation at the platelet surface, or phosphorylation of protein kinase C (PKC) substrates upon thrombin stimulation. In contrast, TWIP steel and pure Fe significantly decreased platelet response to the agonist. Given that similar inhibitory effects were obtained when using a conditioned medium previously incubated with TWIP steel, we postulated TWIP steel corrosion to be likely to release components counteracting platelet activation. We showed that the main ion form present in the conditioned medium is Fe 3+. In conclusion, TWIP steel resorbable scaffold displays anti-thrombogenic properties in vitro, which suggests that it could be a promising platform for next-generation stent technologies.

Effect of silver in thermal treatments of Fe-Mn-C degradable metals: Implications for stent processing

“…Hemocompatibility tests showed that the studied TWIP steels have similar performances to those of 316L SS, which is comparable to what other authors observed [ 13 ]. In addition, the presence of Ag did not cause any decrease in hemocompatibility of the base alloy, similarly to what was reported by other authors on pure Fe [ 44 , 45 ].…”

“…This alloy family possesses equivalent mechanical properties to Co-Cr alloys [ 9 , 10 ] and their high amount of Mn stabilizes austenite at room temperature [ 11 ], whose paramagnetic behavior favors post-implantation imaging [ 2 ]. At the same time, the degradation behavior of such steels is inappropriate in the long-term: several in vitro and in vivo studies found that a stable corrosion layer is formed during the first weeks of implantation, reducing corrosion rate [ [12] , [13] , [14] ]. The addition of Ag to TWIP steels showed the ability to accelerate the short-term corrosion of these alloys [ [15] , [16] , [17] ].…”

Biodegradable Zn-Cu-Fe Alloy as a Promising Material for Craniomaxillofacial Implants: An in vitro Investigation into Degradation Behavior, Cytotoxicity, and Hemocompatibility

“…Regarding biosafety of Fe-based materials, previous in vivo studies revealed no iron excess or organ damage caused by iron-based degradation products, indicating acceptable biocompatibility ( Peuster et al, 2006 ; Waksman et al, 2008 ; Wu et al, 2013 ). According to ISO 10993-4, Fe-based materials exhibited excellent blood compatibility with a hemolysis rate below 5% as well as anti-platelet adhesion ( Schinhammer et al, 2013 ; Verhaegen et al, 2019 ). However, some previous in vivo studies demonstrated that Fe-based implants within physiologic environments had a relatively slow degradation rate and formed insoluble degradation products, adversely affecting the local tissue remodeling ( Pierson et al, 2012 ; Drynda et al, 2015 ).…”

Are Fe-Based Stenting Materials Biocompatible? A Critical Review of In Vitro and In Vivo Studies

“…Assessing blood compatibility is a fundamental part of defining a material as biocompatible. Blood flow across the stent surface could induce erythrocyte rupture, adsorption of plasma proteins leading to platelet activation, and finally, activation of the intrinsic coagulation pathway, resulting in thrombin activation [50]. Some studies have defined Fe-based alloys as biocompatible degradable biomaterials exclusively based on cytotoxicity results, without assessing hemolysis, platelet adhesion or coagulation [18,51].…”