Researchers at the Harvard-affiliated Joslin Diabetes Center in Boston have announced an improvement in mice afflicted with the Duchenne form of muscular dystrophy following treatment with adult stem cells. The results of the study demonstrate for the first time that skeletal muscle precursor cells are capable of repairing muscle tissue and thereby of restoring function in this particular form of muscular dystrophy.

According to Dr. Amy Wagers of the Joslin Section on Developmental and Stem Cell Biology, who is also Assistant Professor of Stem Cell and Regenerative Biology at Harvard University and principal faculty member at the Harvard Stem Cell Institute, “This study indicates the presence of renewing muscle stem cells in adult skeletal muscle and demonstrates the potential benefit of stem cell therapy for the treatment of muscle degenerative diseases such as muscular dystrophy.”

As the world’s largest diabetes research center, the Joslin Diabetes Center employs the world’s most extensive team of board-certified physicians who are actively involved in the treatment of diabetes, with current research encompassing stem cell therapies and applications to other diseases such as muscular dystrophy. Duchene is the most common form of muscular dystrophy, which is caused by a genetic mutation and characterized by rapid muscular degeneration. Previously, all forms of muscular dystrophy have been considered incurable, as standard medicine offers no known safe or effective treatment. Adult stem cell therapy, however, now provides a new modality for the treatment of this disease.

As Dr. Wagers explains, “Once the healthy stem cells were transplanted into the muscles of the mice with muscular dystrophy, they generated cells that incorporated into the diseased muscle and substantially improved the ability of the treated muscles to contract. At the same time, the transplantation of the healthy stem cells replenished the formerly diseased stem cell pool, providing a reservoir of healthy stem cells that could be re-activated to repair the muscle again during a second injury. This work demonstrates, in concept, that stem cell therapy could be beneficial for degenerative muscle diseases.”

Dr. Wagers and her colleagues are focused on studying the cellular mechanisms that regulate migration, expansion and the regenerative potential of hematopoietic as well as skeletal muscle stem cells. Thus far, the cells have proven to offer not only immediate regeneration to damaged tissue but also a reserve pool of cells that provide continuous regeneration and maintenance of the muscles throughout the future life of the muscles.

Imagine a general purpose drug, available to everyone everywhere, which may be bought “off the shelf”, yet which has the natural ability to custom-tailor its efficacy according to the specific needs of each individual patient. Such is the objective of the Indian stem cell company Stempeutics.

Associated with Manipal University and Manipal Hospital outside of Bangalore, but with laboratories in Bangalore and Malaysia, Stempeutics is developing adult stem cell therapies for a vast range of diseases, as most stem cell companies throughout the world are doing today. What sets Stempeutics apart from most others, however, is its design of a stem cell therapy which is not disease-specific, but which is available “off the shelf” and may be used by patients with dissimilar diseases. According to B.N. Manohar, President of Stempeutics, “If a drug that can be stocked and delivered can be made of stem cells, it will bring down the cost of therapy dramatically.”

Throughout the world, specific stem cell therapies are usually administered to patients with specific diseases, yet scientists have already demonstrated certain universal properties of some stem cells which potentially allow for the therapeutic applicability of the cells in a generic sense. It is known, for example, that the differentiation of stem cells into various types of tissue may be regulated by a number of mechanisms which include internal controls such as genetic directions, and external controls such as damaged tissue to which the stem cells automatically migrate. Directed by these various regulating cellular and genetic control mechanisms, therefore, the same collection of stem cells could administered to different patients for different purposes in the treatment of different diseases.

Stempeutics is focused exclusively on the use of adult stem cells, specifically, mesenchymal stem cells, which are “immune privileged” and do not require matching between the donor and recipient. The new therapies have already been tested on several patients with diverse diseases, all of whom are showing improvement.

The company Pfizer is funding the creation of a new biotech company in San Diego called EyeCyte, specifically for the development of a new type of adult stem cell therapy that is targeted for eye diseases.

Dr. Martin Friedlander, an ophthalmologist at the Scripps Research Institute, has identified stem cells in the blood and bone marrow that are capable of repairing damaged blood vessels in the eyes of animals. According to Dr. Friedlander, he has already been able to cure mice in his laboratory by using these stem cells, in research which was funded by the National Eye Institute. When he decided to start a new biotech company that would develop and commercialize such a therapy for humans, rather than pursue the ordinary venture capital route he chose to seek funding directly from Pfizer instead. According to Corey Goodman, president of Pfizer’s biotech unit, “Pfizer has put its flag in the ground that there is a future in regenerative medicine. The eye is a very good place to be starting – it is an isolated organ and there is a huge need.” In April of this year, Pfizer had already initiated a new department for regenerative medicine that was focused on the development of stem cells, and now Pfizer’s top scientists are collaborating with Dr. Friedlander and his colleagues. Thus far Pfizer has committed $3 million to launching the new company, with the right of first refusal to buy the company in a few years if it proves to be successful.

In humans, retinal damage if often the result of diseases such as diabetes and age-related macular degeneration, both of which result in the formation of abnormal blood vessels. Diabetic retinopathy is especially common in certain developed countries such as the U.S., but until now it has only been treatable with laser therapy, the purpose of which is to kill the damaged retinal cells. Now stem cells offer the first type of treatment that can actually repair damaged blood vessels and restore proper blood flow. According to Mohammed El-Kalay, a chief executive at EyeCyte, their first human trials are expected to begin in approximately 3 years. This type of stem cell therapy would compete with drugs such as Lucentis, developed by Genentech, which is currently approved for macular degeneration and is also being tested for diabetic eye disease.

EyeCyte’s therapy strictly uses only the adult stem cells known as CD44, which are injected directly into the afflicted eye. With such a therapy, in the future it would be possible for a patient to visit the doctor in the morning, at which time a blood sample would be drawn from which the CD44 adult stem cells would be isolated, and then the patient would return in the afternoon for an injection into the eye of his or her own autologous purified stem cells, which would heal the damaged blood vessels as well as protect against further damage.

Cardiomyocytes are the fundamental cells of heart muscle, and as such they are critical to the regeneration of damaged heart tissue. Now scientists at Children’s Hospital in Boston have discovered cardiac progenitor cells that are located inside the epicardium, which is the outer layer of the heart.

Some of these progenitor cells were found to express the gene Nkx2-5, while others express the gene lsl1, and a third type was found to express the Wt1 gene. In all cases the cells were shown to be capable of differentiating into heart muscle, vascular smooth muscle cells and endothelial cells. Similar studies conducted at UC-San Diego have yielded the same results with the genetic marker Tbx18. Known as epicardial cells, these stem cells were already proven to be capable of differentiating into endothelial cells and smooth muscle during coronary vessel formation, but this is the first evidence demonstrating that they can also differentiate into cardiomyocytes. According to William Pu, M.D., a pediatric cardiologist at Children’s Hospital, “If you’re going to regenerate a tissue, you need to regenerate the whole tissue, not just the cardiomyocytes. This progenitor population contains all the potential to regenerate multiple tissue types within the heart.”

The discovery is expected to have vast implications in the field of heart tissue regeneration following damage from heart attacks and other types of cardiac injury.

A team of researchers led by Dr. Erick Kurzrock at the UC-Davis Children’s Hospital have isolated the first known stem cells to be found in the adult human bladder. According to Dr. Kurzrock, Chief of the Division of Pediatric Urology at the UC-Davis Children’s Hospital, “This is the first time that candidate adult stem cells of the lining of the bladder have been identified. The main thing that we’ve done is characterize some of the protein expression on the outside of these cells and define what they look like and how they are different from other cells of the bladder.”

According to Dr. Jan Nolta, Director of the UC-Davis Stem Cell Program, “This is an important step. Until now, no one had identified these cells that give rise to the bladder, and there are a lot of people who need replacement bladder tissue, like children with pathological conditions such as spina bifida and adults with spinal cord injuries or cancer. What this means is that for children with many diseases where there is a problem with the bladder we may eventually be able to regenerate the tissue of the bladder. We are currently working on ways to bioengineer replacement organs using stem cells, and now, due to Dr. Kurzrock’s interesting work, the bladder will be one of the candidates.”

Spina bifida and anencephaly are severe birth defects which are both caused by a deficiency in folic acid, which is one of the B vitamins. Although global reports of spina bifida have been decreasing since 1995, the disease is believed to be underreported on birth certificates. In 1999, the U.S. Centers for Disease Control and Prevention (CDC) estimated that approximately half a million cases of spina bifida and anencephaly occur each year throughout the world. While anencephaly is a fatal birth defect and spina bifida also carries a high morbidity and mortality rate, those children who are born with spina bifida and who are able to live to adulthood are permanently disabled. Both diseases are preventable with folic acid supplementation.

In addition to treating children with spina bifida, which is characterized by a loss of the use of the child’s legs and a loss of bladder and bowel control, Dr. Kurzrock also treats children with other conditions and congenital defects of the bladder. According to Dr. Kurzrock, “Most of what I do in my clinical practice is reconstructive surgery. I need a lot of tissue to rebuild things. If we could bioengineer new bladder replacement tissue, that would be great because today we use bowel and stomach tissue.”

As the only comprehensive hospital in the Sacramento region dedicated exclusively to children, UC-Davis Children’s Hospital treats more than 100,000 children each year. Even prior to this recent discovery of stem cells that reside in the bladder, UC-Davis Children’s Hospital was already considered a leader in the use of stem cells for the bioengineering of replacement organs.