The researchers of the Utah State University are using silkworm silk to grow muscle tissue cells, improving traditional cell culture methods and hopefully leading to better treatments for muscle atrophy.
Skeletal muscle cells grown on silkworm have been shown to more closely mimic human muscle tissue.
Three-dimensional cell culture
When scientists try to understand disease and test treatments, they typically grow model cells on Petri dishes. The growth of cells on a two-dimensional surface, however, has its limits: just to say, muscle tissue is three-dimensional.
For this, USU researchers developed a three-dimensional cell culture surface by growing cells on silk fibers wrapped around an acrylic frame. The team used both native and transgenic silk, the latter produced by silkworms modified with spider silk genes.
Native silkworm silk has previously been used for three-dimensional cell culture models, but this is the first time that transgenic silkworm silk has been used for skeletal muscle modeling. Elizabeth Vargis, Matthew Clegg e Jacob Barney of the biological engineering department e Justin Jones, Thomas Harris e Xiaoli Zhang of the biology department published their results in ACS Biomaterials Science & Engineering.
Muscles of silk
Cells grown on silkworm silk have been shown to more closely mimic human skeletal muscle than those grown on the usual plastic surface.
These cells showed greater mechanical flexibility and greater expression of the genes required for muscle contraction. Silkworm silk also encouraged proper alignment of muscle fibers, a necessary element for robust muscle tissue modeling.
The importance of healthy muscle tissue
Skeletal muscle is responsible for moving the skeleton, stabilizing the joints and protecting internal organs. The deterioration of these muscles can happen for a myriad of reasons and can happen quickly.
For example, after just two weeks of immobilization, a person can lose nearly a quarter of their quadriceps muscle strength.
To understand how muscles can atrophy so quickly, a cellular model is needed. Nothing better than cultivated muscle tissue to better represent reality.
“The overall goal of my research is to build better in vitro models,” he says Elizabeth Vargis, professor of biological engineering at USU. “Researchers grow cells on these 2D platforms. They are not realistic, but they give us a lot of information. Then they move on to an animal model, and finally to clinical trials, which fail in the vast majority of cases. With this muscle tissue I would like to add a more realistic and more reliable model."
