Human Embryonic Stem Cell Therapy

When stem cell therapy is mentioned, many people, typically due to media coverage, automatically associate it with embryonic stem cells, and this type of stem cell has its inherent controversies. But stem cell therapies in use today are related to adult stem cells, where there are no inherent controversies.

While the regular clinical use of embryonic stem cells is likely decades away, thousands of patients each year benefit from stem cell therapies that are available today. Adult stem cells tackle conditions ranging from hematological disorders (anemia, leukemia, lymphoma, myeloma) to orthopedic injuries (for joint or soft tissue issues). The former use hematopoietic stem cells while the latter use mesenchymal stem cells from a patient’s own bone marrow (the soft, spongy tissue found in the center of bones).

Embryonic stem cells may one day be the future, but adult stem cells are the safer, more powerful present, improving lives every day.

Here, we want to clarify what embryonic stem cells are and address their theoretical potential use in therapy, including their possible benefits and surrounding controversies.

What Are Embryonic Stem Cells?

Embryonic stem cells are stem cells derived from embryos that are undifferentiated and capable of dividing into different cell types. Embryonic stem cells used by scientists today are derived from embryos created by in vitro fertilization (IVF), meaning they are grown in a laboratory and not taken from embryos in a woman’s body. The embryos are donated to research with the informed consent of the donors.

When embryonic stem cells are grown in a laboratory, they are used to create pluripotent stem cell lines - a group of stem cells that can self-renew and differentiate into any cell type under the right conditions. This is a benefit for science because pluripotent stem cells are basically master cells.

  • First, in the lab, the cell culture can grow indefinitely, meaning theoretically the perpetual recreation of themselves.

  • Second, these cells can change or be changed into almost any type of cell or tissue.

  • Third, because of the latter: we can theoretically make almost any type of cell or tissue we need to repair the body, and the lab has granted us a place to explore indefinite possibilities to advance human recovery and health.

Therefore embryonic stem cells may be important to the future of science and health. At present, however, only the surface of this science has been grazed. There are strict ethical criteria that must be met in order to pursue a stem cell program using embryonic stem cells. Existing human embryonic stem cell lines approved by the National Institute of Health (NIH) for science have been mostly donated from IVF embryos. These donated IVF embryos are poor-quality embryos that would otherwise be discarded as part of the IVF process.

Additionally, embryonic stem cells currently fall into the same tissue category as donor organs, meaning they will be rejected by the recipient’s immune system unless they take anti-rejection drugs. Some genetic manipulation technologies may be able to change this and make embryonic stem cells universally acceptable in the future. But right now these cells aren’t safe or effective to use anywhere outside of a research lab.

What Diseases and Conditions Could Embryonic Stem Cells Treat?

Theoretically, embryonic stem cells may one day be able to treat or cure any number of diseases and conditions..

Some medical and health conditions that may eventually benefit from embryonic stem cell research include:

  • Traumatic spinal cord injury

  • Stroke

  • Severe burns

  • Rheumatoid arthritis

  • Heart disease

  • Hearing loss

  • Retinal disease

  • Huntington’s disease

  • Parkinson’s disease

  • Diabetes

Research and clinical trials are already showing promise with stem cells in regenerative therapy -- adult stem cells included -- in treating serious conditions, like a spinal cord injury, Alzheimer’s disease, muscular dystrophy, blindness, and Crohn's disease. The key to developing more treatments will be in the discovery and expansion of how to direct the stem cells to precisely differentiate into the right cells for each specific disease. Once that’s done, researchers will need to find a way to make these cells acceptable to the recipient’s immune system in order to avoid rejection of the new tissue.

Other Potential Benefits of Embryonic Stem Cells

Apart from possibly helping to treat serious diseases and illnesses, there are other potential benefits to embryonic stem cells.

First, the study of these cells enables us to understand how diseases happen in the first place. Scientists can observe the embryonic stem cells mature and differentiate into cells in all parts of the body, like the bones, muscles, organs, and tissue. As they observe this growth, they record the processes and any incongruencies or diversions from the expected growth pattern.This allows scientists to break down the process of disease development. With this knowledge, we can try to find ways to prevent the development of the disease.

Second, researchers can use embryonic stem cells to test new drugs. New drugs always have the problem of causing unexpected complications, but with embryonic stem cells, testing can be more effective and accurate. As it is, a lot of testing begins with animal testing, and these do not always prove accurate or efficient given that the animal’s biology always differs slightly from human biology.

Is Embryonic Stem Cell Treatment Currently Available in the United States?

Embryonic stem cell treatment is not currently available in the United States. However, the Food and Drug Administration (FDA) has approved some clinical trials of embryonic stem cell-based therapies, but results will not be known for years to come.

These trials take years to meet the stringent testing requirements. Safety and effectiveness are top priority.

Unfortunately, some internationally-based clinics are advertising miracles using embryonic stem cell-based therapies. In fact, these clinics claim the therapy treats incurable diseases. Rumors of this panacea have spread, and desperate patients have sought out their services -- now known as stem cell tourism. These therapies are unproven, come with unknown consequences, and often cost tens or hundreds of thousands of dollars. In our opinion, they are provided by people preying on patients whose illnesses have left them desperate for treatment and hope.

What Is the Controversy with Embryonic Stem Cell Therapy?

In most cases, the development of embryonic stem cell lines requires the destruction of the embryos themselves. Thus, the therapy has become part of the wider, hotly contested debate over the question of when life begins. In other words, is a days-old embryo equivalent to an unborn child, even if it was destined to be destroyed anyway?

While the wider debate continues, the issue is becoming increasingly irrelevant as it applies to stem cell research. We now know that adult stem cells are superior to embryonic stem cells in every way.

Thanks to the discovery of induced pluripotent stem cells (iPSCs), scientists have the ability to reprogram skin or blood cells into any type of human cell required for therapeutic practices, eliminating the need for embryonic stem cells. Adult stem cells are also much safer, as embryonic stem cells are known to carry serious risks of tissue destruction and uncontrolled growth that can lead to the creation of tumors.  

To date, embryonic stem cell research has not produced a single cure. Adult stem cells, however, not only pose promising advances in the future, they are being applied right now in many different ways to treat a wide variety of ailments.      

Is Stem Cell Research Legal in the United States?

The legal nature of stem cell research in the United States is complex and layered. There are no federal regulations that ban embryonic stem cell research in the United States. Some states have effectively banned embryonic stem cell research by prohibiting the creation or destruction of a human embryo for research purposes.

Federally speaking, the confusion about its legality is founded in restrictions on funding. From administration to administration, public funding has been restricted and then lifted. So the federal controversy comes from each administration’s financial support of embryonic stem cell research, or lack thereof.

What Are the Major Challenges Embryonic Stem Cell Research Faces?

Embryonic stem cell research may one day help discover effective treatments and improve lives. The challenges to unleashing this potential, however, are manifold.

Primary challenges include:

  • Embryonic stem cells are not always reliable -- they sometimes differentiate into different cell types even when directed to grow and specialize into another type of cell. They often become large tumors known as teratomas when placed in the adult human body. The challenge, therefore, is controlling this spontaneous, random behavior.

  • The body has an immune system. So when the cells made in a lab, not your body, go into your body, your immune system will reject and attack the new cells. The challenge here is preventing cell rejection.

  • Likewise, when new cells are inserted into the body, they may sometimes function in a manner unintended and the body may react unexpectedly -- often to the detriment of the patient. The challenge here is making the new stem cell therapy safe and effective.

Many people believe the biggest challenge is determining and convincing the public of the ethical implications of embryonic stem cell research. But at this time, the scientific issues listed above pose much bigger problems than the ethical questions. Even if everyone in the world agreed that this type of research should continue, it would still take decades to make these cells safe and applicable in adults. Meanwhile, we already have the technology to create cells with embryonic properties from regular adult cells. And adult stem cells, found in every person, already do amazing things for orthopedic and other conditions today.