The healing powers of our joints are very limited. Similar to a scar, the regenerative cartilage tissue serves primarily as a wound closure and stabilizer. The complex tasks of articular cartilage, which protects the bony corporal hernias from abrasion, can, however, only partly take over. Until now, the medicine can often offer patients with cartilage damage not a satisfactory therapy.
However, a new treatment approach developed by the researchers at the University of Basel provides a reason for hope . As a filler, Ivan Martin and his team use patient-specific cartilage cells – chondrocytes – which they breed in culture. The cells do not gain from the defective joint, as is customary in the conventional procedure, but from the nasal septum wall. Because the nasal cartilage cells have the advantage that they can be reproduced reliably regardless of age and already form in the cell culture a cartilaginous tissue with the characteristic proteins, such as collagen and glycosaminoglycan.
As laboratory experiments and studies in large mammals have shown, nasal cartilage cells also respond to stress – an important prerequisite to be a repair tissue for joint damage. Another advantage of using chondrocytes from the nose is that the defective joint does not have to be further injured. In order to check the safety and the therapeutic potential of their method, Basler scientists have now applied this method for the first time in humans.
The subjects of their pilot project, a total of ten men and women between the ages of 19 and 52, had suffered one or more major cartilage damage on the knee due to an injury. Under local anesthesia, a plastic surgeon first took a tiny piece of cartilage from the nasal septum in each patient. The chondrocytes contained therein were solubilized enzymatically, propagated in the culture dish and sown after two weeks on a collagen framework which promotes the formation of the cartilaginous tissue. Two weeks later the study physicians implanted the now cartilaginous tissue into the cartilage defect at the knee.
Implant grows well
As the orthopedist Marcus Mumme and the other authors write in the “Lancet” (doi: 10.1016 / S0140-6736 (16) 31658-0), the procedure was of lasting benefit to the patient. Thus, in most cases, it was possible to restore the knee function and to alleviate the symptoms or eliminate them altogether. After a rehabilitation period of several weeks, the subjects were able to fully restrain the affected joint and to exercise again. Only a young man had to be excluded due to a series of new sports injuries involving the same knee and other joints.
As a view of the treated knee revealed with the nuclear spin, the implant grew well into the surroundings in all volunteers and after some time showed a similar composition as the natural articular cartilage. This could be confirmed by a biopsy in a patient who had to be re-operated for another cartilage damage at the same knee.
According to the study authors, the implant should therefore have developed into a functionally complete articular cartilage. “This assumption, however, can not be sufficiently substantiated. For this, we would have to take a closer look at the implanted tissue, which can not be done without a new procedure, “admits Martin. “Our studies in goats show, however, that the chondrocytes from the nasal septum have the same structure as the articular cartilage cells.”
While at the beginning they were evenly distributed, the cartilaginous cells arranged themselves in a columnar shape, as hoped for. In a larger study, among which the University of Freiburg participates, the Basel scientists are now testing the procedure with a larger number of knee injured persons. In future, they will also test the method in patients with osteoarthritis, the most common cause of articular cartilage damage. Those affected in particular could benefit particularly.