Clinical performance of artery stents is improved with grafting technique

To overcome postoperation complications such as rejection or reblockage, stents are coated with biological material, which has a higher chance of acceptance by the body. However, scientists remain challenged with maintaining bioactivity and functionality while grafting biological materials.

Diaz-Rodriguez et al. developed a method to graft peptides to the metallic surface of stents. Peptides are excellent for promoting biological acceptance of stents, since they are shown to limit inflammation, improve endothelialization and stimulate necessary biological responses.

The author’s plasma-based, multi-step process is low cost and safe. It allows grafting the peptide by different linking arms. Linking arms affect the way the peptide will interact with the biological environment surrounding the implanted stent.

“Most of the reported literature presents results on flat surfaces, mainly because processes, experiments, and characterizations will provide results easier and with higher reproducibility,” author Mantovani said. “Our results shown that the proposed process was successfully implemented to the 3D step, i.e., the complex geometry of a tiny stent. This represents an evident benefit for accelerating clinical translation.”

The authors method does not require the use of any polymeric coating, which previously led to allergic reactions, rejection and added a step that was difficult to control to the processing.

“The human biological environment is complex, rich and multidimensional,” Mantovani said. “This research can be further explored in several ways; by controlling the density of functional groups inserted into the surface, or by exploring other linking arm lengths to modulate, influence and affect the biological response.”

In a concurrent publication, this method was demonstrated in vivo. The next steps in this research will be clinical trials.

Source: “Comparison of the linking arm effect on the biological performance of a CD31 agonist directly grafted on L605 CoCr alloy by a plasma-based multistep strategy,” by Sergio Diaz-Rodriguez, Caroline Loy, Pascale Chevallier, Céline Noël, Giuseppina Caligiuri, Laurent Houssiau, and Diego Mantovani, Biointerphases (2019). The article can be accessed at https://doi.org/10.1116/1.5120902 .