February 18, 2025

Uy Pham

12th Grade

Fountain Valley High School

The human body contains 78 organs, each with a specific function in allowing our bodies to function in our everyday lives — the heart that circulates blood throughout our body to the spleen which filters our bloodstream from its infectious and abnormal contents. While it may be possible to live without some of these organs, five of these organs are undoubtedly imperative to human survival: the heart, brain, at least one kidney, liver, and lungs. When an organ needs to be replaced, one common process is an organ transplant, where healthy organs from a recently deceased person are used to surgically replace an organ in the donor recipient. 

However, the process of organ transplants largely relies on whether the supply of organs can match the demand for organs to support those in critical conditions and needing assistance to function. For example, with live organs, there is often a limited time frame when the organ can be still viable outside of the human body; while a kidney can survive outside the body for shortly over a day, hearts only have four to six hours before they are no longer viable. Therefore, issues can be posed when there is an ideal organ match, but the time needed to transport the organ from donor to recipient may threaten the success of the organ transplantation procedure. 

There’s also the issue of whether an organ will be even available — often, recipients have a limited time frame when the organ needs to be replaced meaning a match has to be found immediately from a donor. Delivering an organ requires coordination between airports, airlines, and delivery services in a short, urgent time frame. Organs have to be matched based on blood type, and there are different levels of organ donations depending on the blood type; 70% of people with type B blood are minorities, but there may be cultures where organ donation is not culturally accepted. According to the United States Health Resources and Services Administration, over 100,000 people are currently on the transplant waiting list, and every eight minutes another person is added to this list. Kidneys are the most common organ of need, with 89,792 kidney requests as of September 2024. 

Other problems associated with organ transplants include the ethical decisions required to define a person as dead, especially when brain dead, to harvest organs for the transplants. Further increasing the need for the correct match, healthcare providers must work to prevent the transplanted organ from being rejected or causing an infection within the recipient’s body. 

Synthetic organs are any devices or materials created by artificial means (not a live organ from a live donor) that can be used to carry out the function of the organ it's intended to replace. The types of synthetic organs are generally classified as mechanical, made of plastic and metals; biological, made of living cells; and biomechanical, containing the parts of both mechanical and biological organs. Therefore, synthetic organs can replace the need to search for and preserve an organ for a transplant procedure, as the organs can be artificially created in an optimal location and to match the biological requirements of the recipient. 

Through this system, organ donor recipients would not have to wait for an optimal organ to be available from someone else. It’s even suggested that artificial intelligence electrocardiographs can make post-transplant care easier, compared to the current manual monitoring procedures carried out by healthcare providers, and by eliminating the need for immune suppressor medication necessary to avoid rejection of an organ transplant. 

The process can be summarized by six general steps: imaging, design, material, cell, printing, and application. Although the process varies depending on the type of organ, a template is initially designed based on the other model cells and tissues from the recipient themself, as required as the model tissue or organ. Scaffolds act as support for the tissue to regenerate based on the body’s own tissue and cells. If the organ involves cells, the cells must be preserved and mature, while cell-encapsulated printing inks may take part of the artificial parts of the organ. Cells must be fed every 24 hours with nutrients until the cells are mixed with a gel (bioink) to simulate the function and biological properties of cells. 

The potential polymers to be used differ based on their biological and chemical properties, which can in turn create limitations dependent on the synthetic organ’s intended function. Between the different printing methods, including inkjet, laser-assisted, and stereolithography, medical providers must decide how to balance the print speed, cost, and cell viability, among other factors. The process of printing can be compared to a color printer — color prints utilize different color inks to create a color print, while biological printers utilize different cells as the different inks for the final organ. Some of the processes are automated, while others may require a component of manual function. It is estimated that it takes several hours to print, and then another four to six weeks to be implemented into the recipient’s body. 

Toward the future, full implementation of synthetic organs as a replacement for the common organ transplant process is estimated to take between 20-30 years as researchers continue developing ways to balance the process of synthetic organ creation with the biological needs of its recipient. Recent developments by UC San Francisco and Cedars-Sinai are focused on growing organs themselves from the recipient’s cell, focusing on regeneration rather than the printing process. Current topics researchers are invested in improving include how to ensure that the cells are mature enough to completely simulate the human body. 

For example, procedures to create artificial ears and noses involve utilizing cells and cartilage from other parts of the recipient’s body to grow the organ. At the Massachusetts Institute of Technology, researchers printed a heart from soft polymer-based ink based on a 3D model of the recipient’s heart; the created model resembled the shape of the recipient’s original heart. With the typical transplant for kidneys costing nearly half a million dollars, despite the cost of these printers and maintenance, the entire synthetic organ process may end up costing nearly $100,000 for medical patients.