New approach to treating arthritis discovered

According to researchers from the Queen Mary University of London (QMUL), arthritis patients will be able to benefit from a new type of treatment.

The study that was performed showed that arthritic cartilage, which was until now thought to be unaffected by any kind of therapy, could be treated by a patient's own ˜microvesicles' which have the ability to travel into cartilage cells and deliver therapeutic agents.

Microvesicles are small subcellular structures that are 0.05 to 1 micrometer in diameter. They consist of a fluid enclosed by a membrane. These structures are released by cells in large numbers to transfer biological compounds such as lipids and proteins to target cells. However, their role in disease has not yet been completely understood. In most cases, the microvesicles of white blood cells accumulate in the joints of rheumatoid arthritis patients.

Cartilage has always been long thought to be impenetrable to cells and other small structures, and thus also impenetrable to therapy. Surprisingly, microvesicles coming from white blood cells are able to ˜travel' into the cartilage and are also able to deliver their cargo, which also has a protective effect on the cartilage.

Our study indicates that these vesicles could be a novel form of therapeutic strategy for patients suffering from cartilage damage due to a range of diseases, including osteoarthritis, rheumatoid arthritis, and trauma. Treating patients with their own vesicles may only require a day in the hospital, and the vesicles could even be ˜fortified' with other therapeutic agents, said lead author Mauro Perretti from QMUL's William Harvey Research Institute.

The study was published in Science Translational Medicine and was funded by the organization Arthritis Research UK, the Nuffield Foundation (Oliver Bird Fund), and the Wellcome Trust. It examined the role of microvesicles in some mice models and human cartilage cells in which the researchers investigated their effect on experimental arthritic disease.

Arthritis and Microvesicles

In their experiments, they used mice that were genetically modified to have reduced microvesicle production. Causing experimental inflammatory arthritis on these genetically modified mice exhibited cartilage damage. However, when these same mice were treated with microvesicles, the cartilage degradation was reduced. Doing similar experiments to human cartilage cells showed that the treatment of microvesicles also resulted in cartilage protection.

The researchers also found that one particular receptor was involved in these effects. The receptor, known as ˜FPR2/ALX', was shown to be involved in the protection of cartilage tissue. Because of its involvement, it could therefore be a good target for the treatment of cartilage-damaging arthritis-related seases with the use of small molecules.

By using the body's own transport system to get new and current therapeutic agents directly into the cartilage, holds the promise that we will be able to reduce joint damage more effectively than ever. A healthy and intact joint results in less pain and disability improving the quality of life of millions of people
living with arthritis in the UK, said Stephen Simpson, who is Arthritis UK's Medical Director.
The researchers indicate that this may prove to be a new approach for the treatment for damaged
cartilage due to arthritis. Further studies in humans may also needed to confirm the actual therapeutic
potential of this new type of treatment.