Cardiovascular disease is one of the most common causes of death worldwide with many studies into ways to combat it. Now, researchers in Germany have found that spider silk may be able to boost artificial tissues used for repairing injured hearts. The group has published the work in the journal Materials Today Bio.
The study shows for the first time that cardiac muscle cells, known as cardiomyocytes, could attach to recombinant spider silk. “Cardiomyocytes attached to spider silk films contract and respond to pharmacological treatment,” says Tilman Esser. The goal is to use this material in artificial tissues to help improve the function and behaviour of cardiac muscles, potentially reducing heart problems in the future.
Problems of the heart
The heart cannot repair itself on its own, so cardiac tissue engineering is used to replace or repair injured heart muscle. Here, supporting materials provide structures for the basic requirements of cardiac muscle cells, and influence their behaviour so that cardiac muscle cells can thrive in artificial environments and integrate both physically and functionally with the receiving heart.
The first artificial cardiac tissues were made a quarter of a century ago, with many studies since investigating the function of artificial cardiac tissues in vitro and in vivo. Suitable biomaterials for cardiac tissue engineering are limited, so the research team looked outside the box and examined spider silk, using techniques such as molecular cloning, recombinant protein production and biochemical analysis to generate spider silk protein variants.
Spider silk proteins are useful because they repel bacteria and fungi while at the same time assisting in the regeneration of human tissue. It is hoped this could make them effective in implants, wound dressings, prostheses and even contact lensesin the future. “Spider silk based materials are promising biomaterials due to their biocompatibility and adoptability, and due to the fact that mechanical properties can be engineered to match those needs,” says Thomas Scheibel, of the University of Bayreuth in Germany, who led the spider silk research.
Felix Engel at the Friedrich-Alexander-Universität Erlangen-Nürnberg in Germany, tested the suitability of spider silk proteins for artificial cardiac tissue. “To increase the chances to successfully translate our data into clinical practice, it is important to develop predictive human engineered cardiac tissues to model cardiac diseases, as well as to screen for therapeutic drugs and repair injured hearts,” says Engel.
In recent years, a particular type of stem cells called hiPSCs (human-induced pluripotent stem cells) have become a major focus in tissue engineering as they can be derived from patient cells and easily genetically modified by CRISPR/Cas9 to monitor specific processes or to introduce disease-specific mutations. Such stem cells are seen as having potential in regenerative medicine, and as they can propagate indefinitely and give rise to every other cell type in the body, represent a single source of cells for replacing those lost to damage or disease.
“Since recombinant spider silk can be modified and tailored to the specific requirements, synthesised in appropriate yields, easily processed and shows no immune-reaction, it is very promising for tissue engineering and other biomedical applications,” says Vanessa Trossmann, a group member from the University of Bayreuth in Germany.
Esser, T. U. et al.: “Designing of spider silk proteins for hiPSC-based cardiac tissue engineering,” Materials Today Bio (2021)
