As has been widely hyped for many years now, mesenchymal stem cells have the capacity to heal all sorts of damage in our bodies. The reality has been more complicated, since it is actually very difficult to get these cells to perform their magic just where we want them to.

Damaged cartilage, for example, doesn’t heal well on its own and so would be a prime beneficiary of well targeted stem cell therapies. Current injection methods are not very effective, but researchers from South Korea’s Chonnam National University and Korea Institute of Medical Microrobotics are reporting in journal Science Robotics on specially designed “microrobots” that can carry and deliver mesenchymal stem cells (MSCs) precisely to sites of damage within knee cartilage.

The microrobots are tiny spheres with pores within which MSCs can reside in. The microbots can be moved around using a magnetic field, and an external 3D magnetic system is used to target the microbots toward specific areas of cartilage. Once injected and placed at their final destination, the microbots can be kept there using a simple magnetic band wrapped around the knee while the stem cell differentiate and turn into healthy tissue.

This approach has already been successfully tried and tested on lab rabbits, successfully helping to heal damaged knee cartilage. The results of this study may help the research team move their technology from the lab stage toward clinical trials.

Study in Science Robotics: Human adipose–derived mesenchymal stem cell–based medical microrobot system for knee cartilage regeneration in vivo