‘Living hip’ grown in lab may stop arthritis

Breakthrough offers hope for 160,000 patients who need to have hip or knee replacements each year

ARTHRITIS sufferers have been offered new hope after scientists grew a “living hip” in the lab which replaces worn cartilage and stops pain returning to joints.

Researchers in the US have used stem cells to grow cartilage in the exact shape of a hip joint while also genetically engineering the tissue to release anti-inflammatory molecules to fend off the return of arthritis.

The cartilage is implanted around the joint to extend its life before arthritis has caused too much damage to the bone. Severe loss of cartilage can lead to bone rubbing on bone, altering the shape of the joint and forcing the bones out of their normal position.

In the UK around eight million people suffer from osteoarthritis, which occurs when cartilage starts to rough- en and becomes thinner. The technology could offer an alternative treatment for the 160,000 people in Britain who need hip or knee replacements each year, without the need for metal prosthetics.

The breakthrough may benefit younger patients, who are often told to wait until the age of 50 for surgery as current prosthetics only last for up to 20 years, and surgery to replace them risks further bone damage and infection.

Dr Farshid Guilak, professor of orthopedic surgery at Washington Uni- versity, said: “We’ve developed a way to resurface an arthritic joint using a patient’s own stem cells to grow new cartilage, combined with gene therapy to release anti-inflammatory molecules to keep arthritis at bay.

“Our hope is to prevent, or at least delay, a standard metal and plastic prosthetic joint replacement.”

The technique uses a 3-D, biodegradable synthetic scaffold which is moulded into the precise shape of a patient’s joint and then covered with stem cells taken from fat beneath the skin.

The scaffold is built using a weaving pattern that allows the stem cells to transform into the structure and shape of normal cartilage.

Because the implant is made from a patient’s own stem cells, there is no risk of rejection.

The scientists have genetically engineered the cartilage to release anti-inflammatory molecules when the patient takes a drug.

“When there is inflammation, we can give a patient a simple drug, which activates the gene we’ve implanted, to lower inflammation in the joint,” said Dr Guilak, also a professor of develop- mental biology and of biomedical engineering. Gene therapy is important because when levels of inflammatory molecules rise in a joint, the cartilage is destroyed and pain increases.

Dr Franklin Moutos, vice president of technology development at biotech firm Cytex, which helped develop the implant, said the tissue had been shown to withstand stresses placed on joints.

The team hopes to start testing on humans within five years. The research was published in Proceedings of the National Academy of Sciences.