Need new cartilage? Grow your own

A NEW technique to "knit together" torn knee tissue using stem cells is set to be tested in patients within the next year, scientists in Edinburgh were told yesterday.

Professor Anthony Hollander, who was part of the team that transplanted a windpipe made using stem cells into a patient last year, said researchers now hoped to mend torn knee cartilage – a common injury among young sportsmen and women.

It is thought the technique could prevent patients suffering serious knee problems, including osteoarthritis, for years to come. More details of the trial are set to be announced in the next month.

Researchers around the world, including in Edinburgh, are also exploring the use of stem cells in knee and bone injuries.

Prof Hollander's work came to the public's attention in November, with the news that 30-year-old Claudia Castillo had received a windpipe engineered using her stem cells to replace her own damaged tissue.

Speaking at a Scottish Stem Cell Network conference in Edinburgh yesterday, the Bristol University researcher told scientists about that work and his plans for future trials. These include patient tests of a stem cell technique to mend tears in the part of the knee cartilage known as the meniscus.

Alan McLaren, the former Hearts and Rangers defender, had a cruciate ligament injury. His treatment left him with no cartilage, bringing his playing career to an end.

Prof Hollander told The Scotsman: "At the moment, there's no way to treat this (cartilage].

"It is just cut out, and that leaves the patient very susceptible to osteoarthritis within a short number of years."

He said the technique, which will be tested initially on ten patients, involves implanting stem cells on a membrane into the middle of the lesion and sewing it up.

"It is designed in a way that the cells will migrate across the lesion and literally knit it together," he said. "So, instead of growing new tissue, it's healing the lesion itself."

The stem cells used will come from the patient's own bone marrow, reducing the chance of them being rejected.

Funding has now been secured for the trial and regulatory approval is being sought.

Dr Brendon Noble, from Edinburgh University's centre for regenerative medicine, said his team was also using stem cells to mend damaged knee tissue and was hoping to start trials in the next year.

He said the aim of all the different pieces of research was to find the best way of repairing cartilage but that, in future, their biggest goal was tackling osteoarthritis.

"In our studies, we are not going to go to that immediately. We are starting with the contained defects – the little holes in the cartilage – and try to repair those first," Dr Noble said.

Prof Hollander also revealed plans for further trials of transplants involving the stem-cell engineered windpipe, or trachea. It involves taking a section of windpipe from a donor which is stripped of its own cells, with the patient's own stem cells then attached to the scaffold.

Prof Hollander said five more patients had been identified around Europe who could benefit from the treatment if they secured further funding.

He said they also hoped to start trials using laboratory-made voice boxes in the next five years. The technique could potentially be used for a range of organs, including the large blood vessels and intestine.