Clinical Study Evaluates Healing of Knee Cartilage With Stem Cells


The biotechnology company InGeneron will test its patented Transpose RT system in a clinical study that examined the ability of regenerative cells from a patient’s own fat to enhance cartilage healing after knee surgery.

Qualified patients are being recruited through the Fondren Orthopedic Group in Houston. According to the American Orthopedic Society for Sports Medicine, over 4 million knee arthroscopies are performed worldwide each year. Damaged knee cartilage is very difficult to treat and can lead to chronic pain and long-term disability.

Robert Burke, who is serving as the principal investigator of this clinical study, is an orthopedic surgeon with the Fondren Orthopedic Group in Houston. Burke thinks that stem cells taken from a patient’s own fat may enhance cartilage healing. He studied adding patient-derived regenerative cells to the knee during arthroscopic surgery for particular patients, and compared them to patients who had arthroscopic surgery without added fat-derived stem cells.

Arthroscopic surgery is a common procedure is commonly used to treat damaged cartilage, and the patients who had received arthroscopic surgery were randomly chose to either receive fat-derived stem cells or not receive them. Burke, will then monitor these patients for the next 12 months after surgery to determine if the added cells improved cartilage healing.

According to Burke, “Articular cartilage, the smooth surface covering the joints at the ends of bones, has no good way of healing on its own. The body doesn’t create enough new cartilage of the same type to repair the damage.” Better treatments would use various techniques to help the body make new cartilage.

“Stem cells and other regenerative cells that we can obtain fat have the potential to do that,” said Burke. Such regenerative cells can divide and mature to form several types of cells and tissues. and are found in multiple places in the body. Fat that lies just below the skin is one of the easiest places to obtain stem cells.

The InGeneron Transpose RT System uses a small amount of fat, which is removed and processed to separate out the regenerative cells. The separated adipose tissue-derived mesenchymal stem cells are then immediately placed into the area of damaged cartilage during knee surgery. Once in the knee, these cells may divide to make new cartilage cells.

This kind of biological activity has been seen in laboratory studies and veterinary medicine. However, Burke’s study will be one of the first to test the technology in humans for treating cartilage damage. Like other types of stem cell-based therapies, the treatment is not currently licensed for human use in the United States but it is registered in Europe, Mexico, and other countries. Following the Texas Medical Board’s rules about the use of stem cells for treatment, this study is under the supervision of the research review board at Texas Orthopedic Hospital, where all of the patients will undergo surgeries.

This is a two-year study.

Tissue Engineers Use New Biomaterial to Repair Knee Cartilage


Tissue engineers from Johns Hopkins University School of Medicine’s Translational Tissue Engineering Center (TTEC) have used a biomaterial to stimulate and facilitate the growth of new cartilage in human patients.

An illustration of the cartilage repair surgical procedure. A mini-incision exposes the cartilage defect (top left-hand panel), and any dead tissue is removed from the edges. (B) The adhesive is then applied to the base and walls of the defect, followed by microfracture. (C) Lastly, the hydrogel solution is injected into the defect. (D) Bleeding from the microfracture holes is trapped in and around the hydrogel.Science Translational Medicine/AAAS
An illustration of the cartilage repair surgical procedure. A mini-incision exposes the cartilage defect (top left-hand panel), and any dead tissue is removed from the edges. (B) The adhesive is then applied to the base and walls of the defect, followed by microfracture. (C) Lastly, the hydrogel solution is injected into the defect. (D) Bleeding from the microfracture holes is trapped in and around the hydrogel.
Science Translational Medicine/AAAS

This was a rather small study that only examined 15 patients. All 15 patients had cartilage defects and were scheduled to undergo “microfracture surgery.” Microfracture surgery uses a drill to bore tiny holes in the bone. These small holes allow bone marrow stem cells to leak into the joint space and make new bone and cartilage. In this study, hydrogel scaffolding was troweled into the wound to in order to support and nourish the healing process. The results from this study were published in the Jan. 9 issue of Science Translational Medicine. According to the authors, this study is a proof of concept trial that paves the way for larger trials to test the hydrogel’s safety and effectiveness.

“Our pilot study indicates that the new implant works as well in patients as it does in the lab, so we hope it will become a routine part of care and improve healing,” says Jennifer Elisseeff, the Jules Stein Professor of Ophthalmology and director of the Johns Hopkins University School of Medicine’s TTEC. Cartilage damage results from overuse, injury, disease or faulty genes. Microfracture surgery is a standard of care for cartilage repair, but when holes in cartilage are caused by joint injuries, microfracture surgery often either fails to stimulate new cartilage growth or grows cartilage that is less hardy than the original tissue

To address this problem, tissue engineers, such as Elisseeff, have postulated that the bone marrow mesenchymal stem cells need a nourishing scaffold on which to grow in order to make the right type of cartilage and enough of it. Unfortunately, demonstrating the clinical value of hydrogels has been slow, difficult, and expensive. By experimenting with various materials, Elisseeff and her colleagues have developed a promising hydrogel, and an adhesive that sticks the hydrogel to the bone.

After testing the combination for several years in the lab and in goats, the hydrogel seemed ready for human trials. Elisseeff and her group collaborated with orthopedic surgeons to conduct their first clinical study. 15 patients with holes in the cartilage of their knees received a hydrogel and adhesive implant along in combination with microfracture surgery. In order to compare the efficacy of their hydrogel, another three patients were treated with microfracture surgery alone. After six months, it was clear that the hydrogel implants had caused no major problems. Furthermore, magnetic resonance imaging of these patient’s knees showed that patients with implants had new cartilage filling an average 86% of their defects in their knees, and patients that had received only microfracture surgery had an average of 64% of their tissue replaced. Patients with the implant also reported a greater decrease in knee pain in the six months following surgery, according to the investigators.

As the trial continues, more patients have enrolled. This clinical trial is presently managed by a company called Biomet. These data from this trial is part of an effort to earn European regulatory approval for the device.

Elisseeff and her team have begun developing a next-generation implant in which the hydrogel and adhesive will be combined in a single material. Elisseeff and others are also interested in technologies for joint lubrication that reduce joint pain and inflammation

Glucosamine, Chondroitin and Delaying Osteoarthritis


I have a confession to make. I have been taking 1200 mgs of glucosamine sulfate for the past 5-6 years for my knee cartilage. I do not presently have osteoarthritis, but I am trying to stave it off by taking this supplement.

Does this supplement work? That’s hard to say for certain because the studies disagree. There are theoretical reasons to suspect that glucosamine would help with cartilage deposition. Cartilage is very rich in a group of sticky, sugary compounds called “glycosaminoglycans,” which have the unfortunate acronym of GAGs. GAGs consist of repeating two-sugar motifs, and the building block for the vast majority of these two-sugar motifs is glucosamine. Therefore, glucosamine is a main building block of a prominent component of cartilage.

What about chrondroitin? Chondroitin is a GAG that usually comes attached to a protein. This complex of GAG + backbone protein is called a “proteoglycan.” The chondroitin you get in the store is a repeating polymer of a two-sugar motif, and this complex molecule is either degraded in your digestive system by bacteria, or by our own gastrointestinal tract.  The degradation and absorption of chondroitin probably varies considerably from person to person.  If chondroitin is absorbed then the building blocks of chondroitin can potentially help build cartilage, since chondroitin-containing proteoglycans are important structural components of cartilage.  There is also the possibility that chondroitin precursors prevent the breakdown of cartilage.

Chondroitin_sulfate-over

In 2006, a good-sized study called the GAIT study was published in the New England Journal of Medicine (Clegg, D.O. et al. (2006). Glucosamine, chondroitin sulfate, and the two in combination for painful knee osteoarthritis. New Eng. J. Med. 354(8):795-808). In this study, 1583 patients with symptomatic knee osteoarthritis were randomly assigned to different treatment subgroups. These groups were:

a) chondroitin sulphate alone (400 mg 3x a day)
b) glucosamine hydrochloride alone (500 mg 3x a day)
c) combined glucosamine hydrochloride/chondroitin sulphate (same doses but combined)
d) celecoxib (Celebrex®) (200 mg per day)
e) placebo (inactive dummy tablet)

Daily dosages for glucosamine and chondroitin were 1500 mgs and 1200 mgs, respectively. The efficacious dosage for these supplements have yet to be determined. Therefore, these dosages are a best guess. Celecoxib was included as a positive control for the GAIT study, since celecoxib is FDA approved for the management of osteoarthritis pain. Therefore, investigators therefore expected participants in this group to experience some pain relief, which would serve to validate the results of the GAIT study.

The GAIT study found that when patients were divided into two groups based on pain levels, 1,229 had mild pain and 354 had moderate to severe pain. With regard to the effectiveness of these supplements, neither glucosamine nor chondroitin sulphate either on their own or in combination were effective in reducing pain. However, when only those patients with moderate to severe pain was analyzed the combination of glucosamine and chondroitin sulphate was effective for pain relief. Unfortunately, no cartilage thickness studies were performed to determine if the supplements augment cartilage thickness. The GAIT study was publicly funded, and therefore, accusations of conflict of interest could not be used to discredit this study.

in 2005, results from the GUIDE study were presented at the 2005 Annual Meeting of the American College of Rheumatology. This study was funded by glucosamine manufacturers and examined of pain and mobility in 318 osteoarthritis sufferers between the ages of 45 and 75 at 13 European hospitals. Participants in this study were divided into three groups:

a) glucosamine sulphate in soluble powder form 1500mg daily
b) acetaminophen (e.g. Tylenol® and paracetamol) 3000mg daily
c) placebo

In addition, subjects in all three groups were allowed to take ibuprofen as needed as a ‘rescue’ for pain relief.

The GUIDE study found that glucosamine sulphate and acetaminophen were more effective in reducing pain than placebo. Patients who took glucosamine sulphate experienced greater pain relief than patients on acetaminophen.

The GUIDE and GAIT studies were positive for glucosamine and chondroitin, but there are negative studies too. In October 2004, Jolanda Cibere and others published a study in the journal Arthritis Care and Research in which they gave glucosamine or a placebo to arthritis suffers and then discontinued them. 42% of the patients receiving the placebo experienced a disease flare-up and 45% of the glucosamine-receiving patients experienced a flare-up. Also, the time to disease flare was not significantly different in the glucosamine compared with placebo group. Thus Cibere and others concluded that “this study provides no evidence of symptomatic benefit from continued use of glucosamine sulfate.”

The bottom line on all this is the glucosamine and chondroitin perform inconsistently in controlled studies. When poor-quality studies are excluded, glucosamine seems to delay arthritis. The highly respected Cochrane Library published a summary of human clinical trials with glucosamine and when the poor-quality trials were excluded, Towheed and his colleagues concluded that glucosamine provided relief of the symptoms of arthritis and also, based on X-rays, helped delay the onset of osteoarthritis.

However, the European Food Safety Authority reviewed over 60 articles on glucosamine and came to a completely different conclusion. In 2012, the EFSA concluded that “The Panel concludes that a cause and effect relationship has not been established between the consumption of glucosamine and maintenance of normal joint cartilage in individuals without osteoarthritis.”

In 2009, in the Journal, Arthroscopy, Vangsness, Spiker, and Erickson came to a somewhat blasé conclusion, “glucosamine sulfate, glucosamine hydrochloride, and chondroitin sulfate have individually shown inconsistent efficacy in decreasing OA pain and improving joint function.”

The long and the short of it is that these supplements might work. Furthermore, my best guess at this point is that they probably work better for some people than for others. So should you take glucosamine or even chondroitin? All our information at this point says that it is safe to do so. No serious or even moderate side effects have been observed by taking these supplements. Secondly, they might work for some people. How do know if you are one of them? By taking the supplement.

I realize that this post is probably very unsatisfying to many of you, but some are very enthusiastic about glucosamine and chondroitin, and I think that this enthusiasm needs to be tempered by a hard dose of reality.  There is much we simply do not know at this time about the efficacy of these supplements, and more work needs to be done before we can say anything definitive about them.   A recent study shows that large doses of chondroitin (1200 mgs) are effective at reducing symptoms in patients with osteoarthritis of the knee, but given the vagaries of chondroitin absorption (see above), it is unlikely that we can make any hard and fast conclusions about it.

One more note about these supplements.  Several studies have shown that the quality of over-the-counter glucosamine vary considerably.  Be careful what you buy and from whom you buy your supplements.  Consumer Reports has shown that some supplements are even spiked with prescription drugs!  So caveat emptor and do not believe the marketer’s own statements about their supplements.

A Co-culture System Makes Better Cartilage for Tissue Replacement


At joints, the bones are covered with cartilage to act as a shock absorber. Articular cartilage, or cartilage at joints, is usually characterized by very low friction, high wear resistance, but very abilities to regenerate. Articular cartilage is responsible for much of the compressive resistance and load bearing qualities of joints, and without it, even activities as simple and walking is too painful. Osteoarthritis is a condition that results from cartilage failure, and limits the range of joint motion, increases the bone damage and also causes a respectable amount of pain. When the cartilage of the articular surface erodes, the bone is exposed and grinding of the bone creates bone spurs, extensive inflammation and pain.

Treating osteoarthritis requires that one make new cartilage that has similar properties as articular cartilage. Unfortunately, mesenchymal stem cells that are differentiated into cartilage making cells (chondrocytes) and implanted into the knee tend to make fibrocartilage, which is different than the hyaline cartilage that composes articular cartilage. Fibrocartilage does not possess the high-wear resistance characteristics of hyaline cartilage and it tends to erode rather rapidly after formation. Therefore, directing mesenchymal stem cells (MSCs) to form proper cartilage is a genuine challenge.

A paper that appear in Stem Cell Translational Medicine from Gilda A. Barabino, who is a faculty member at the Wallace H. Coulter Department of Biomedical Engineering at Georgia Institute of Technology and Emory University, examines a technique to coax MSCs to make articular cartilage.

As Barbino points out, traditional protocols that direct MSCs to differentiate into chondrocytes uses culture systems of MSCs that have been treated with various growth factors, such as transforming growth factor-β. Unfortunately, these culture systems tend to fall short in meeting the needs of clinical applications, largely because they yield terminally differentiated cells that enlarge and then form bone.

In this study Barbino and her co-workers co-cultured bone marrow-derived MSCs with juvenile articular chondrocytes. The rationale is that the MSCs would receive just the right growth factors in just the right concentrations and at the right time to drive MSC cartilage formation. Physical contact between cells can also do a better job of driving them to differentiate into various cells types rather than simply treating them with growth factors.

Barbino and others discovered that an initial chondrocyte/MSC ratio of 63:1 worked the best and the MSCs form chondrocytes that had the right cells shape, behavior, and characteristics of articular chondrocytes.

Next, Barbino and her team grew the MSCs in a three-dimensional agarose system. Three-dimensional systems are generally thought to more realistically recapitulate the cartilage-making system present at joints. In this 3-D culture system, when co-cultured with juvenile articular chondrocytes, bone marrow MSCs develop into robust neocartilage that was structurally and mechanically stronger than the same cultures that only contained chondrocytes.

There was another advantage to this culture system; cultured MSCs that are induced to form cartilage tend to cease all expression of a surface protein called CD44, which is an important regulator in cartilage biology. However, when cultured in the 3-D culture, the MSCs retained the expression of CD44, which suggests that these co-cultured MSCs, which cultured in a 3-D culture system form chondrocytes that make superior articular cartilage, but retain CD44, which allows cartilage maintenance.

This shows that making articular cartilage from MSCs is probably possible and only requires the right culture system. Also, co-culturing MSCs with articular chondrocytes in a 3-D culture system might be one of the better culture systems for developing clinically relevant cartilage for tissue replacements.

NBC’s The Doctors to Feature Centeno Clinic and Regenexx Stem Cell Procedures on Wednesday, January 25, 2012


Tomorrow (Wednesday, January 25th, 2012), the popular TV show “The Doctors” will feature the Centeno/Schultz clinic and their orthopedic stem cell treatment known as “Regenexx.” On hand will be Dr. Hanson from the Centeno clinic (unfortunately Dr. Centeno was in China for the studio taping), and a former Regenexx patient named Barbee James. Ms. James had knee cartilage breaks and received the Regenexx-C knee stem cell procedure in 2008. The stem cell-treated knee is doing quite well, but the other knee, which was surgically treated with a failed micro fracture procedure, is now in need of a stem cell treatment. See a preview of the show here.