Last week there was an article in Fierce Biotech Research titled “Doctor Calls for Boost in Cord Blood Stem Cell Research,”the article describes the potential of cord blood cells and discusses some of the areas where cord blood is being studied as a treatment for disease.
I decided that this presented a good opportunity to revisit the subject on The Dish and to outline some of the current uses of cord blood, clinical studies, and research opportunities along with a discussion of potential hurdles to success.
Current Uses of Cord Blood Stem Cells
Cord Blood Stem Cells vs. Bone Marrow
Currently, cord blood is most commonly used in the treatment of childhood leukemia. Cord blood offers advantages over treating the disease with bone marrow transplants. In an earlier blog titled “UC Davis Set to Launch California’s First Public Umbilical Cord Blood Bank,” we outlined some of the primary advantages of using cord blood over bone marrow including:
- Shorter time from donor match to transplantation – Frozen cord blood cells can be shipped immediately. With bone marrow donation, the donor has to be contacted, permission has to be given, and testing and collection has to be conducted before cells are available for transplant.
- Cord blood is easy and painless to obtain – Bone marrow collection on the other hand can be painful for the donor and a potential donor has to be tested with their information on the registry to be selected as a match. Unfortunately many people may be matches and don’t realize it.
- Cord blood is easier to match donor and patient due to reduced immunogenicity in cells coming from a newborn – HLA matching is the method used when determining a match for transplant. The process, used with both bone marrow and cord blood matching, looks at 6 proteins in the blood. Bone marrow requires 5 of 6 proteins to match to be a donor, but in cord blood only 4 of 6 proteins have to match. It is estimated that around 25% of people needing a bone marrow match will not find it and cord blood donations could help reduce this percentage significantly.
Potential New Therapies for Disease
Cord blood stem cells are also being studied as a way to treat many diseases including, Juvenile (Type 1) diabetes, pediatric stroke, traumatic brain injury, Cerebral Palsy, Autism and many others. A few of the trials are described in more detail below:
- A clinical study for traumatic brain injury (TBI) in pediatric patients. TBI is one of the leading causes of death in children and those that survive often have serious brain disabilities. A Phase I TBI study beginning at UT Health is using a patient’s own cord blood that was banked for them as newborns. This study will enroll 10 children between the ages of 18 months and 17 years with moderate to severe TBI. Treatment will be administered within 6-18 months of injury and will have safety as the primary endpoint. Dr. Charles Cox, Director of the Pediatric Trauma Program at Children’s Memorial Hermann Hospital and principal investigator, is leading the study.
- A clinical study for Autism. The double blind, placebo controlled study, conducted by the Sutter Neuroscience Institute will enroll thirty children between the ages of 2-7 years old. Over thirteen months, the children will receive either two infusions of their own cord blood (banked at birth) or two infusions of placebo. There is evidence that some children with Autism suffer from a dysfunctional immune system and this study will examine whether the cord blood cells can help to repair the damaged immune system of these children.
- A clinical study for Cerebral Palsy. Georgia Health Sciences University is conducting a placebo controlled study on forty children between the ages of 1-12. There is research in animals indicating that an infusion of stem cells can induce healing in the brain. This study will look at whether cord blood cells can help to repair damage in the brain.
Cord Blood Stem Cells for Research
One group conducting extensive research using cord blood is The University of California, Davis Institute for Regenerative Cures. The philosophy behind the UC Davis Institute is to bring together physicians, research scientists, biomedical engineers and other experts to work in disease teams all with a focus on moving research into clinical trials. There are 14 disease teams that address every major area of the human body and the Institute has planned or initiated clinical trials in retinal occlusion, heart attack, peripheral vascular disease, bone repair and Huntington’s disease. The Institute is also home to one of the largest GMP (Good Manufacturing Practice) facilities for stem cells in the nation. It has 7,000 square feet of space with a suite of six specially designed rooms created to safely process cellular and gene therapies for clinical trials.
A major research tool for the Institute is the use of neonatal stem cells in research applications. The neonatal stem cells are collected from placental tissues and cord blood. Researchers at the Institute study neonatal cells in a number of ways. One way researchers use these cells is to compare the neonatal cells of a newborn with any health problems they may have had at birth to see if there is a link on a cellular level. They are also studying the environment of these cells in the placenta to find better ways to culture stem cells. Perhaps the most revealing studies done on these cells are when researchers create “disease in a dish” scenarios. One example conducted at the institute was on newborns at risk for Huntington’s disease. Researchers isolated hematopoietic stem cells from the cord blood of newborns at risk for Huntington’s disease. The cells were cultured, induced into a pluripotent state and were differentiated into neurons. By studying these neurons they could see if the neurons were developing normally and they could examine how the neurons responded to various drugs as a way to look for cures or to slow progression of the disease. This “disease in a dish” model is applicable across a wide range of disease types and allows researchers to conduct extensive research about a disease without invasive patient procedures.
Potential Hurdles to Success
While there are many exciting opportunities available using cord blood there are also some challenges that need to be overcome. One of the primary challenges is that there the percentage of donors is very low. In the Fierce Biotech Research article, Dr. Mary Laughlin, a physician and expert in marrow and stem transplants at the University of Virginia School of Medicine, stated, “cord blood is only saved from about 4% out of all births. Those are very useful cells that are going in the trash.” One possible solution is a focus on educating parents on the value and importance of donating their child’s umbilical cord. Another important consideration is creating more public cord blood banks to collect, store, test, and register cells on donor registries.
Another possible challenge is the number of cells collected from each umbilical cord and the possibility that there may be an insufficient amount to provide the number of cells necessary for treatment. One possible solution would be to culture and expand the cells to increase the number of cells. Another improvement could be the use of better, more consistent collection techniques and optimal culture to ensure the highest number of cells possible.
What are some of the other possibilities or challenges to the use of cord blood cells in disease treatment and research? How do these advantages/challenges compare with the advantage/challenges of using induced pluripotent stem cells?