A group of researchers from Perelman Medical School at the University of Pennsylvania demonstrated a new possible way to repair complex body tissues that can lead to longer treatment of common injuries such as cartilage degeneration. The study was published in Advanced Materials.
We found that we can organize objects, such as cells, so that they can generate new complex tissues without having to change the cells themselves. Others had to add magnetic particles to the cells to react to the magnetic field, but this approach can have undesirable long-term effects on cell health. Instead, we manipulated the magnetic nature of the environment surrounding the cells, which allowed us to place objects using magnets.
Hannah Zlotnik, the first author and graduate student of bioengineering research at McKay Orthopedic Research Laboratory in Pennsylvania.
In humans, tissues such as cartilage can often break down, causing joint instability or pain. Often the destruction is not complete, but covers the area, forming a hole.
The treatment now assumes that the holes are filled with synthetic or biological materials that can work, but often wear out because they are not the same materials as before. This is similar to how potholes are sealed on the road: they are filled with gravel. In this case, the pit will be smoothed out, but over time this construction will wear out because it is not the same material and it cannot be glued together in the same way.
A group of scientists discovered that by adding magnetic fluid to a three-dimensional hydrogel solution, cells and other non-magnetic objects, including microcapsules for drug delivery, can organize certain patterns that mimic natural tissue by using an external magnetic field.
After a brief contact with the magnetic field, the hydrogel solution (and the objects in it) were exposed to ultraviolet light in a process called “photo stitching” to fix everything in place. The magnetic solution was then dispersed. The designed tissues then maintained the necessary cellular gradient. With this magnetic simulation technique, the team was able to recreate articular cartilage.