Regenerative Medicine and Organ Transplant

Susana Fares Mazloum

During the recent years, we have seen an expansion in the transplantation medical field, due to the aging of the baby boomer generation  (people born between 1946 and 1964). Unfortunately, the demand for tissues and organs has exceeded the number of donor organs.

According to recent statistics, an estimated 500,000 patients in America benefit from a type of yearly tissue or organ transplant. Statistics have also shown that in 2017 there were nearly 116,369 people on the waiting list for donor organs.

Creating living, functional organs and tissues as a substitute for those that were damaged because of disease, congenital defects, aging, or accidents is the main purpose of the research in the regenerative medicine field.

In the past

The successful transplantation of bones, soft tissues, and corneas was first recorded during the 20th century. However, the main advances in the field were noted in 1954 when the first successful kidney transplant was confirmed (Fig.1). Later on, in the 1960s, the successful transplantation of other organs such as the liver, kidney, pancreas, and heart was registered in scientific literature. Furthermore, successful transplant surgeries of a lung, a heart and lung, and a liver and lung took place during the 1980s.

first kidney transplant
Fig.1: First successful kidney transplant. Source: Stanford/History

In The Present

A sad reality is that many of the individuals on the organ transplant waiting list may not live until a donor or suitable organ can be found to be compatible. 20 people die each day waiting for a transplant. However, with advances in the regenerative medicine field, it is possible to use tissue-engineered skin in cases where a skin replacement is needed. Tissue-engineered skin may also be used for temporarily covering wounds on burn victims, and has been helpful in the treatment of leg and foot ulcers in diabetic patients. Other successful engineered tissue types currently available are tissue containing islet cells, forming an artificial pancreas that assists diabetic patients. There has also been success with transplanted engineered cartilage and the use of biological materials to induce connective tissue growth, bone growth and regeneration, vascular grafts that aid in heart bypass surgery and cardiovascular disease treatments, oral mucosa, bone marrow, and bone (fig.2).

bone
Fig.2: Engineered bone with functional marrow. Credit: Varghese lab, UC San Diego

Currently, regenerative medicine makes it possible to grow some types of whole or partial organs using a patient’s own cells. The organ can be grown outside the body and implanted into the patient. Some successfully engineered and transplanted organs are the trachea (windpipe), bladder, blood vessel (fig.3), penis, ear, and vagina.

vessel
Fig.3: Engineering blood vessels. Credit: Robert Emilsson

Currently, researching scientists are trying to engineer essential organs. Mini organs have been successfully engineered, such as mini hearts, brains (fig.4), lungs and livers. Scientists are also studying the possibility of using the technology to repair spinal cord injuries.

brain
Fig.4: Engineered mini brains. Credit: Johns Hopkins Hospital

In the future 

The hopes for the future are that regenerative medicine will improve the quality of life for individuals in need of a transplant by providing healthy, functional tissues and organs.

The aim is that when there is a shortage of organ donors, science can help artificially create the needed organ. Victims of spinal cord injuries can one day have the opportunity to walk again and weakened or injured hearts can be replaced with healthy ones. This is the long-term promise that the scientific community is trying to achieve through regenerative medicine, a fast-growing field with an immense potential to transform the way human disease is treated and transplantation is performed–to offer novel therapies that are rapid, safe and complete.

Edited by: Daryn Dever, Karen Yung, and Kaylynn Crawford

Kaul, Himanshu, and Yiannis Ventikos. “On the Genealogy of Tissue Engineering and Regenerative Medicine.” Tissue Engineering. Part B, Reviews 21.2 (2015): 203–217. PMC. Web. 15 Nov. 2017.

Peloso, Andrea et al. “Current Achievements and Future Perspectives in Whole-Organ Bioengineering.” Stem Cell Research & Therapy 6.1 (2015): 107. PMC. Web. 15 Nov. 2017.