Researchers say a patient's own microvesicles - small particles released by cells - could help treat arthritis.
Microvesicles are tiny, fluid-filled particles - around 0.5-1 micrometer in diameter - that are released by cells in large numbers. While it is known these particles transfer lipids and proteins to other cell types, their role in disease remains unclear.
According to the research team - led by Prof. Mauro Perretti of the William Harvey Research Institute at Queen Mary, University of London in the UK - microvesicles released from some white blood cells, such as neutrophils, tend to accrue in the joints of patients with rheumatoid arthritis.
But what do these microvesicles do once they reach the joints? This is what the team decided to investigate by analyzing genetically modified mouse models of arthritis and human cartilage cells from patients with the disease.
Their findings are published in the journal Science Translational Medicine.
Microvesicles could deliver arthritis drugs to cartilage cells
It is widely believed that cells and other small particles are unable to penetrate cartilage, making delivering therapies to the joints of patients with arthritis very challenging.
- Osteoarthritis is the most common form of arthritis
- Two thirds of people with arthritis are under the age of 65
- Around 22.7 million people with arthritis experience limitations in day-to-day activities as a result of the condition.
From their research, however, Prof. Perretti and colleagues found that microvesicles released from neutrophils have the ability to enter cartilage - a discovery that could open the door to novel treatment strategies for arthritis.
By studying mouse models of arthritis that were genetically modified to have reduced microvesicle production, the team found the mice demonstrated greater cartilage damage. When treated with microvesicles, however, cartilage damage was reduced.
On treating human cartilage cells from arthritis patients with microvesicles released from neutrophils, the researchers found they protected the cells from damage. They identified one cellular receptor in particular - called FPR2/ALX - that played a key role in protecting cartilage tissue.
Arthritis is the most common cause of disability in the US, affecting around 1 in 5 adults. There is no cure for the condition, but there are medications and non-pharmacologic treatments available to help manage symptoms caused by the condition.
However, with the number of people with arthritis in the US expected to rise to 67 million by 2030, there is a need for broader treatment options for the condition. The researchers believe their findings could fulfill this need and could even provide new treatments for other conditions.
Prof. Perretti says:
"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 hospital, and the vesicles could even be 'fortified' with other therapeutic agents, for example, omega-3 fatty acids or other small molecules."
The team says further studies are needed to determine the potential of translating their findings into a new therapeutic approach for arthritis.
In September, a study reported by Medical News Today revealed how yoga may improve symptoms for people with rheumatoid arthritis and osteoarthritis.