Cartilage under load

Human cells were first grown on the skeleton of an anthropomorphic robot

Sergey Vasiliev, Naked Science

Tissue engineering technologies are only developing, scientists and doctors are still looking for ways to grow complex three-dimensional structures from living cells in order to someday receive new organs for transplantation. So far, such experimental procedures allow obtaining only relatively simple tissues from the patient's cells, such as cartilage, devoid of an internal network of vessels and nerves. You can even grow a trachea, but with joint cartilage, the replacement of which is so relevant for many patients, it is still not possible to do this.

In fact, for the normal growth of cartilage tissue of joints and tendons, cells need constant and varied loading, stretching and bending. To ensure these conditions, doctors have been trying to use automation for a long time. Special devices continuously stretch and relax the sample growing in the bioreactor throughout the entire process, but even this does not allow you to get a full-fledged cartilage, elastic and durable. A new approach to this task is described in an article by researchers from Oxford University published in the journal Nature Communications Engineering (Mouthuy et al., Humanoid robots to mechanically stress human cells grown in soft bioreactors).

British scientists have decided to replace conventional devices for stimulating growing cartilage with a more complete anthropomorphic robot. More precisely, the shoulder joint, which was developed for a humanoid robotic skeleton by Devanthro engineers. The Roboy design is distributed freely, under an open license, and scientists led by Professor Pierre-Alexis Mouthuy reproduced it in the laboratory, making only some improvements so that the joint more accurately imitated natural human movements.

In addition, they have created elastic bioreactors for growing fibroblasts, the main cells of cartilage and other types of connective tissue. The cells are placed on elastic plastic substrates that stretch between a pair of solid blocks. Such a reactor, seeded with cells that are continuously supplied with oxygen and nutrients, scientists fixed in an artificial shoulder joint for 14 days. For half an hour a day, the robot "trained", making various movements to create the necessary loads on the growing tissue.

The authors found that cells grow faster in such conditions than in immobility, and even the profiles of genetic activity in them differ. So far, scientists have not conducted a detailed analysis of these differences and cannot prove with facts and figures in their hands that the samples grown on the robot are better suited for transplantation — they have left this work for the future. Nevertheless, Professor Muti's team believes that they have made an important demonstration of the principle, and now their colleagues in other laboratories around the world can improve the method of growing tissues in elastic bioreactors, on the details of anthropomorphic machines.

Portal "Eternal youth" http://vechnayamolodost.ru