3D-Printed Organs - The Future of Organ Transplants?
By William Huang
The need for organ transplants continues to rise. The supply of organs available for transplantation is already far smaller than the demand, and the demand may grow substantially in the near future. Furthermore, valid organs must match a patient’s blood type, size, severity for a transplant, and the proximity from a possible organ to them. This is a huge risk for the patient’s health. Therefore, having a consistent supply and production of compatible and effective organs whenever there is a need will greatly aid in this problem.
According to a 2006 study by Marilia Cascalho and Jeffrey Platt, the future of organ replacement will be dependent on three variables. The first variable is the need, particularly how the number of organs to be replaced will change over time. The second variable is the new technologies that will be available to replace those organs. The third variable is the set of obstacles, biological and societal, that may hinder the replacement of organ function. With 3D bioprinting technology that can be used to manufacture artificial organs, we may have a solution for the future transplantation of organs.
Organ bioprinting is the use of 3D-printing technologies to assemble multiple cell types, growth factors and biomaterials in a layer-by-layer fashion to produce organs that imitate their natural counterparts, according to a
2019 study. To begin the process of bioprinting an organ, doctors typically start with a patient's own cells. They take a small needle biopsy of an organ or do a minimally invasive surgical procedure that removes a small piece of tissue. They then grow this piece of tissue inside a sterile incubator or bioreactor, which is a pressurized stainless steel vessel that helps the cells stay fed with nutrients. The doctors feed them every 24 hours, since cells have their own metabolism. Each cell type has a different media, and the incubator or bioreactor acts as an oven-like device mimicking the internal temperature and oxygenation of the human body. Then then mix the cells with a glue, a printable mixture of living cells, water-rich molecules called hydrogels, and the media and growth factors that help the cells continue to proliferate and differentiate. These hydrogels mimic the human body's extracellular matrix. To avoid a negative immune response, the biomaterials used typically have to be nontoxic, biodegradable and biocompatible. Collagen and gelatin are two common biomaterials used for bioprinting tissues or organs.
Afterwards, doctors load the glue into a printing chamber, "using a printhead and nozzle to extrude an ink and build the material up layer by layer". Creating tissue with varying properties is enabled by printers being programmed with a patient's imaging data from X-rays or scans.
The length of the printing process depends on several factors, including the organ or tissue being printed, the resolution of the X-rays, and the number of printheads needed. The average process typically lasts a few to several hours. The overall print from biopsy to the implantation is about four to six weeks
Although these printed organs might not be able to provide a complete replacement to organs unlike donations just yet, their production can also help reduce the chance of death while waiting for a transplant. Many individuals have cited that the quality of life significantly increased if a replacement increases their organ function by several percent.
Citations:
https://www.science.org.au/curious/people-medicine/bioprinting
Image Credit:
https://www.engadget.com/2014-06-20-3d-printed-organ-explainer.html
