Stem cell therapy for osteoarthritis

13th July 2010 - A new form of treatment for osteoarthritis using cultured stem cells is to undergo clinical trials in the UK which it’s hoped could one day lead to new ways of helping the estimated eight and a half million people with the condition.

The trial will test the effectiveness of stem cells derived from bone marrow (also known as mesenchymal stem cells) at repairing worn cartilage in those with osteoarthritis of the knee.

The cultured stem cells will be tested against cultured cartilage cells (chondrocytes). Chondrocytes are currently used to repair small areas of cartilage damage, although they are not used to treat osteoarthritis. The cells are extracted from a patient, grown in the lab and then re-implanted back into the patient.

The mesenchymal stem cells will be tested against chondrocytes, and a combination of both types of cell will also be trialled with the aim of repairing joints, stopping osteoarthritis getting worse and delaying - or even avoiding - the need for knee replacement surgery.

Trial at specialist Shropshire hospital

Up to 70 patients with osteoarthritis of the knee will take part in the trial at The Robert Jones and Agnes Hunt Orthopaedic Hospital in Oswestry, Shropshire.

The hospital is at the forefront in the UK in using a Swedish surgical technique of extracting cartilage stem cells from patients with cartilage problems, a process called autologous chondrocyte implantation (ACI). Surgeons also have extensive experience of using stem cells from bone marrow to repair bone fractures.

A team led by scientist Sally Roberts, Professor of Orthopaedic Research, and James Richardson, Professor of Orthopaedic Surgery at Keel University, believe that they can produce enough healthy new cartilage cells for the technique to be applied to patients with osteoarthritis.

Two operations

Participants in the trial will be recruited from orthopaedic departments throughout the UK, on the advice of local specialists. Those enrolled in the trial will undergo two operations. The first involves removing the patient’s cartilage or bone marrow stem cells using keyhole surgery. The cells are then grown in the lab for three weeks. In the second operation, the cultured cells are re-implanted back into the area where the knee cartilage is damaged or worn.

The process involves a six month period of convalescence and rehabilitation, but the surgical team say the implanted cells should eventually form new cartilage.

Participants will be followed up for a year, with success measured by the quality of the cartilage and the patient’s ability to perform everyday activities.

The trial is being funded by the medical research charity, Arthritis Research UK, as part of a five year £500,000 research programme at Oswestry.

‘No magic bullet’

“We are the first laboratory in the UK producing mesenchymal stem cells and chondrocytes for treating patients, so we are unique in being able to test the effectiveness of both types of cell therapy,” Richardson says in a statement announcing the trial, which is scheduled to begin later this year.

However, the team warn that stem cell therapies are experimental and patients won’t find they suddenly have the joints of a 15 year old. Roberts says in a statement: “At the moment they are not the ‘magic bullet’ and they don’t solve the underlying problem of osteoarthritis, which still needs to be addressed. They have been hyped up. They certainly have huge potential - we just need to learn how to harness it properly.”

The Oswestry team caution that routine clinical use is probably still several years away, whatever the outcome of the trial.