Mechanism decoded: That is why rheumatoid arthritis becomes chronic
Rheumatoid arthritis is the most common inflammatory joint disease. Patients suffer from restricted mobility and pain. The inflammatory response in the joint is extremely chronic, which is why lifelong therapy is usually required. Researchers have now found out why rheumatoid arthritis becomes chronic. The new findings could help to improve therapy.
Permanently inflamed joints
According to the German Society for Rheumatology (DGRh), rheumatoid arthritis is the most common inflammatory joint disease. Popularly referred to in this context as "rheumatism". “With this disease, several joints are usually permanently inflamed. As a result, they can gradually deform and stiffen, ”explains the Institute for Quality and Efficiency in Health Care (IQWiG) on its patient information portal“ gesundheitsinformation.de ”. Now researchers have found out why rheumatoid arthritis becomes chronic.
Defense cells attack the joint
Rheumatoid arthritis results in a chronic inflammatory reaction, in which the body's own defense cells attack the joint, including cartilage and bone. This process does not stop spontaneously.
An international team of researchers led by the rheumatologist Dr. Andreas Ramming from the Friedrich-Alexander University Erlangen-Nuremberg (FAU) has now identified a cell type of the immune system that specifically controls a stop of the inflammatory response in arthritis.
The results of the scientists were recently published in the journal "Nature Medicine".
Mostly affected women
According to a statement from the university, around 800,000 people, mostly women, suffer from rheumatoid arthritis in Germany.
Persistent inflammation damages the joints and bones. Patients suffer from restricted mobility and pain.
"What is particularly dramatic for those affected is the fact that the inflammatory reaction in the joint is extremely chronic and therefore usually requires lifelong therapy," explains Prof. Georg Schett, Director of the Medical Clinic 3 - Rheumatology and Immunology at the University Hospital Erlangen.
In rheumatism, drugs are usually used that, in addition to pain relief, have the important function of preventing or at least slowing down permanent damage to the joints.
Sometimes natural remedies, such as radon heat therapy in warm healing tunnels, help against the pain associated with rheumatism. So far, however, rheumatism has not been cured.
Congenital lymphocytes in rheumatic people in hibernation
So far, according to the scientists, little was known about how inflammation resolves and why this resolution does not work for rheumatics.
By collaborating with scientists in London, Barcelona, Zurich, Indianapolis and Dublin, the Erlangen researchers have now succeeded in solving this riddle.
A so far little-researched cell group of the immune system, the so-called innate lymphoid cells (English Innate Lymphoid Cells), play the central role in resolving inflammation, explains the Erlangen-based immunologist Simon Rauber, first author of the study.
“In patients with rheumatoid arthritis, these congenital lymphocytes are in a kind of hibernation. The inflammation therefore persists. 'If you wake up congenital lymphocytes, the inflammation stops and the damage to the joint ends,' says study leader Dr. Ramming.
The discovery of this important mechanism could represent a completely new approach to the development of innovative treatments for chronic inflammatory diseases.
New options for monitoring therapy
Measuring the number of congenital lymphocytes in the blood already enables a prognosis of the course of treatment. If there are only a few congenital lymphocytes in the blood, the disease will spread and the joint will be further damaged.
However, if the congenital lymphocytes increase, this is associated with a resolution of the inflammation. By measuring them in the blood, an individual, more targeted therapy can be started at an early stage and the patient can be saved from a renewed onset of illness.
"This finding will make it possible in future to significantly improve the quality of therapy for rheumatoid arthritis with the help of congenital lymphocytes," explains Dr. Ramming. (ad)