Nov 20, 2017
Are stem cells harvested from fat the future?
Professor Claude Moorman uses a long needle to inject tumescent solution into his patient’s abdomen before agitating the tissue with tiny karate chops. The solution liquidates the fat under the skin enabling him to suck it out using a liposuction catheter. He passes the fat to technicians working at a table behind him and begins an arthroscopy (keyhole surgery) on his patient’s arthritic shoulder.
While he cleans out the joint and releases some of the scar tissue, the technicians rinse the fat with saline to remove impurities and shake it vigorously in a cylinder full of ball bearings to isolate the most active stem cells. Professor Moorman then completes the procedure by injecting the stem cells into his patient’s shoulder using his arthroscope to make sure they hit precisely the right spot.
This process of extracting stem cells from fat and injecting them into arthritic joints is now routine at Duke University in North Carolina where Professor Moorman is Director of Sports Medicine. Patients with milder arthritis are injected with stem cells without the accompanying surgery.
“Here at Duke we’re trying to study this with the usual amount of scepticism you have in an academic medical centre,” Professor Moorman told our reporter. “We’ve come to believe that fat-derived cell therapy probably has some advantages over bone marrow.”
Professor Moorman described the procedure at a recent meeting of orthopaedic surgeons organised by the Arthroscopy Association of North America (AANA) in Chicago, Illinois.
“It was exciting to see a presentation at the prestigious AANA from a leading orthopaedic surgeon who is using fat-derived stem cells in his work,” said our principal Mr Simon Moyes, who attended the event. “We are already treating patients with stem cells extracted from bone marrow but we have always known that fat-derived cells are more powerful.”
Fat yields ten times more stem cells than bone marrow, Professor Moorman said. He added: “The second major advantage is that over the ageing process you lose active cells in bone marrow but with fat the number of activated cells stays steady throughout a lifetime – an 80-year-old’s fat is just as good as a 20-year-old’s. The third advantage where I am is we have people who eat a lot of BBQ and biscuits and they have plenty of adipose tissue!”
However, slim patients can be more challenging. “Usually you can harvest from the love handles but occasionally you have to roll patients over and get it from the gluteal area,” he said.
Although liposuction is used to extract the fat, the amount harvested is generally not enough to have a cosmetic effect. The process can also cause pain and bruising.
In the UK orthopaedic surgeons use stem cells from bone marrow mainly because they are more accustomed to working with bones than fat.
Do stem cells work?
Stem cells, whether from fat or bone marrow, are the new frontier in orthopaedic medicine (indeed, in all medicine) but do they actually work?
“That’s the million dollar question,” said Professor Moorman. “The truth is nobody knows the answer. It’s going to take years of research to really sort it out.”
Professor Moorman has provided stem cell therapy to 30 patients with early shoulder arthritis and over 90 per cent have been “meaningfully” helped. Over 100 patients with knee arthritis have also been treated. Around 70 per cent of those with mild to moderate arthritis were helped but many of those with severe arthritis went on to have knee replacements despite the stem cell treatment.
“Our early sense is that patients with shoulder arthritis are the most promising group,” he said. “We’ve learned that we can’t help all the patients with severe knee arthritis but we’re very encouraged by what we are seeing with the less severe patients.”
Stem cells seem to have an impact at two stages in the recovery process accelerating healing for around six weeks, probably due to their anti-inflammatory qualities, and then boosting healing again around three to four months after surgery, which may indicate they are actually regenerating tissue.
It’s this possibility that has excited people leading some to compare stem cells to the Holy Grail in the movie Indiana Jones and the Last Crusade – pour them on and human tissue fizzes back to life.
“When you talk about stem cell therapies as the Holy Grail that sums up what a lot of people feel about it especially people in very desperate straits looking for cures,” said Professor Moorman.
“It’s going to require more study and time to sort out the appropriate indications and be realistic about what people can expect but if we can get the right minds working on it the upsides are tremendous and I really think it could be the next great paradigm in musculoskeletal medicine helping keep patients much more comfortable and active through their lives.
“We hope to have an ability to restore cartilage in patients with mild to moderate osteoarthritis who are not yet candidates for or interested in joint replacement.”
Mr Moyes, who has treated over 20 patients with stem cells derived from bone marrow in the past year, added: “People are excited about stem cells because of all the buzz but we need long-term randomised double-blind studies because the number of patients being treated currently is too small to draw statistically significant conclusions.