Scientists have discovered a new way to replicate the regenerative power of stem cells in the laboratory, which could lead to powerful treatments for injuries and diseases. In a paper published in the journal ACS Nano, Dr Catherine Berry and Professor Matthew Dalby from the University of Glasgow’s Institute of Molecular Cell and Systems Biology, describe how they have been able create and control bundles of bone marrow stem cells that act as the stem cells do in the body. These bundles of cells are capable of healing injuries in laboratory‐grown bone and cartilage models.
Mesenchymal stem cells are produced naturally in the body and have the unique ability to differentiate into many other different types of cells, such as bone, cartilage or fat cells. They have enormous potential for use in medicine but they are difficult to culture in the laboratory, because, when stored outside of the body, they spontaneously and randomly differentiate. In vivo, they wait in the bone marrow until a regenerative demand is placed on them. Then, they differentiate into mature cell types to repair the bone, cartilage, ligament or tendon around them.
Using 3D spheroid cultures rather than standard 2D cell growth techniques, the researchers have shown that they can grow stem cells and prevent them from differentiating over a prolonged period. To achieve this, they added magnetic nanoparticles to each stem cell. Then, using a magnet, they built ball‐shaped masses of around 10,000 stem cells, just big enough to see with the naked eye, over the course of just a few hours. When placed in soft gel, similar to the consistency of bone marrow, these balls of cells remain as stem cells over long culture periods, with no unwanted differentiation. When placed next to an injured area, they quickly became active again, migrated towards the injured tissue, and began to
differentiate in the same way they would in the human body to heal a wound.
As well as in understanding regeneration of the musculoskeletal system, the tiny marrow stem cell models could be used to test drugs designed to activate the stem cells, and have applications beyond bone, cartilage and ligament repair.