Long before the term ‘Regenerative Medicine’ was coined, humans were realizing the effects and capabilities of medicinal intervention. The Ancient Civilizations of Sumeria, Egypt, China, India, and South America all pioneered medical discoveries and techniques that still impact the field today. Practices that we take for granted, such as cleansing and debridement of wounds using vegetable and mineral concoctions were commonplace, and skin graft procedures for facial reconstructions were recorded by Sushruta, an Indian physician, over 1,000 years ago.
Hundreds of scientists and philosophers over thousands of years have worked to establish our current technologies. In the 1st century CE, Roman doctor, Celsus, recorded his discovery of the four signs of inflammation (heat, pain, redness, and swelling). C.F. Wolff’s studies on chick embryos in the late 1700s proved that development occurs in a series of epigenetic steps (modifications of DNA that are involved in development). The early 1800s saw a huge expansion in the fields of biology and medicine when scientists revealed that all life depends on chemical reactions that occur within cells, which could, in fact, be reproduced in the laboratory. The discovery and official introduction of antibiotics by Alexander Flemming in 1928 changed the field of health-care forever. Followed shortly after by the discovery of cell division and heritability in the form of a helical, ladder-like structure, called DNA, science was geared to bring ‘a whole other ball game’. These discoveries meant that human biology and the systems contained within could now be brought into and manipulated in the laboratory. As the turn of the 20th century hit, previously mystical processes of life science finally become tangible.
For thousands of years, regeneration has been a topic of interest (although not necessarily termed as such) amongst the scientific world. Records dating back to the 8th century BC confirm that the theory of regeneration was indeed acknowledged, although not entirely understood. This is depicted in ancient Greek mythology. Recounted by Homer and Hesiod, the Legend of The Titan god Prometheus, narrates his suffering. After offending Zeus by stealing fire from Olympus to aid mankind, Prometheus was banished to the Carpathian Mountains. He was chained to a rock and left to be tortured for 30,000 years as the eagle, Ethos, came each night to pick at his liver. Doomed by immortality, his liver would regenerate each day, only to endure the same fate again that evening. The Ancient Greeks were on to something, in naming the liver, ἧπαρ (hepar), after ἠπάομαι which means “to repair oneself”; they clearly understood the liver’s capability to regenerate. We now know that the liver is the only organ in the body that can regenerative itself spontaneously after injury.
Tissue grafting made an impact in the early 16th century by surgeons, Cosmas and Damian, who inspired paintings such as, “Transplantation of a leg by Saints Cosmas and Damian, assisted by angels” (Stuttgart, Germany). As tradition goes, they attempted to replace a patient’s diseased leg with a moor’s leg, leaving him with one white and one black leg.
It is easy to see that medicine has been evolving for thousands of years and we are just now truly tapping into the underlying mechanisms that govern its regulation and recapitulation. Humans and animals have been utilizing these means since the dawn of creation and now scientists in the field of Regenerative Medicine seek to move beyond the sole application of medical techniques and onto understanding the concepts, patterns and, mechanics behind regeneration to create more opportunities for comprehensive therapies that may one day be able to send an amputee home with a functional leg or relieve a diabetic from insulin injections by replacing the islets within the pancreas.
Regenerative medicine has grown from prior activities including surgery, surgical implants (artificial hips), and increasingly sophisticated bio-material scaffolds (skin grafts). The work that truly launched regenerative medicine into a tangible area of science began as cell therapy. Work in the field of transplantation in the mid-1950s gave rise to some of the first therapeutic surgeries in medicine. Performed on identical twins, the first kidney transplant occurred in 1954 followed by the first liver and lung transplants in 1963, pancreas transplant in 1966, and the first heart transplant in 1967. Bone marrow transplants for treatment of leukaemia patients had the public and scientific communities in an uproar of excitement. Following this wave of enthusiasm, cell biologists began to question the capabilities of the integrity of the tissues being transplanted and wondered whether it was possible to create, grow, and harvest these tissues in the laboratory. Thus began the era of Tissue Engineering which has lead us into the field of Regenerative Medicine.
Reference: Regenerative Medicine: Gustav Steinhoff, 1st Edition 2011 XXIV, Springer Publications.