My fascination in the use of stem cells lies in their potential to replace tissue that has been lost or destroyed, such as bone, muscle and cartilage. This is because a stem cell can not only renew itself, it can also undergo differentiation – that is, it can produce a different type of cell. The degree of differentiation varies between types of stem cells, from a totipotent cell (one able to make all cells) to a unipotent cell, which can only make cells of one type.
Trauma, failure for a bone to repair after a fracture, and infection are among the more common causes of bone loss and damage I see in my practice. Although my interest is mainly orthopaedic, the first research in this area was done in response to the threat posed by nuclear warfare. Research on the effects of radiation in WWII led to the demonstration of stem cells, which until then had only been hypothesised. As a result, stem cell transplantation has become the standard treatment for many blood disorders, such as leukaemia.
The discovery that various cells may be taken from an individual and induced to become a pluropotential cell (one which can produce many types of cells) offers unprecedented opportunities for regenerative medicine. In theory, a patient’s own cells might one day be used to regenerate their own tissue.
Currently, the main limitations in stem cell therapy seems to be just how the transplanted cells will integrate into the surrounding tissue to achieve both the desired biological and physiological effect. Despite decades of research, there has been limited practical success. From my own experience, I’ve seen a good initial response form stem cells injected onto a joint where cartilage has been lost, but the joint began to fail again shortly afterwards. More research is needed.
Which cell, or combination of cells, will prove the ideal for bone healing remains to be answered.
Through the study of stem cells, however, we have gained greater understanding of how cells grow, repair and regenerate. Even if human treatment fails to eventuate, the knowledge discovered in the research regarding our understanding of bone repair and regeneration will in itself lead to new therapies.
Although stem cells offer enormous potentials, the research remains in its infancy. I believe stem cells therapy will be part of our medical repertoire in the near future, and I look forward to being a part of this branch of medicine.