According to the US National Institutes of Biomedical Imaging and Bioengineering, regenerative medicine is a field that focuses on how the human body regenerates, repairs or replaces cells and tissues using its own systems to do so. The body uses its own materials to do this, but sometimes does this with the help of foreign biological material as well.1 The goal of regenerative medicine is to exchange either tissue or organs that have been damaged by age, disease, damage or congenital defects as opposed to treating only symptoms.2
The field of regenerative medicine is not new. In fact, the first skin graft can be dated back to 3000 BC, as described in the Sanskrit texts of India.3 People have been writing about regenerative medicine since the prehistoric ages.
The Greek philosopher, Aristotle, wrote that animals that are in the early developmental stages have a higher potential for regeneration in his works on natural history. He wrote in depth explanations about regeneration on the limbs of salamanders and deer antlers. As time went on, theories ranged about the function of the human body, whether it was controlled by chemical and physical properties or by a divine source. It wasn’t until the 19th century that regenerative medicine saw a great deal of development. For example, cell theory was defined as cells being the elementary units of life and were thought to replicate themselves by dividing. Research was done in the 1900’s that showed germ cells were able to replicate themselves into many different types of tissues. Specifically in 1981, Gail Martin generated a diploid cell line that was able to generate into any type of tissue in the adult body of mice. She called her cells “embryonic stem cells.” Human embryonic stem cells were isolated in 1998 by James Thomson and the field has been growing ever since. Since that time, the field of regenerative medicine has greatly expanded.4 Efforts are now focused on skin replacement and the repair of cartilage, blood vessels, liver and heart tissue.
The first successful transplantation of bone, soft tissue and corneas occurred early in the 20th century. It wasn’t until 1954 that the first kidney transplant was performed. In the 1960’s, there was a successful transplantation of pancreas/kidney, liver, and heart.
Development in the field of regenerative medicine has made great strides since the first skin graft was written about thousands of years ago. Currently, there are many sources of stem and precursor cells e.g. embryos, gestational and adult tissues, and reprogrammed differentiated cells. By having many different sources of the cells, there can be more sophistication, variety and usefulness of the engineered tissues. For example, tissue-engineered products are being used to help start bone and connective tissue growth and replace damaged knee cartilage. A tissue-engineered bladder that is grown from a patient’s own cells, can then be grown outside the body and successfully transplanted.5 In 2016 approximately 500,000 Americans receive transplants every year, while there are over 120,000 people on the waiting list for an organ.6
Fields within Regenerative Medicine:
Stem cell therapy
Hormone replacement therapy
Ultraviolet blood irradiation therapy
Brain training neurofeedback