An estimated 21 people may pass away each day from needing organ donations. There are many reasons a person may need an organ transplant: aging organs, failure due to disease, or trauma such as a car accident. Many men, women, and children wait months or even years for life-saving surgeries.
Without a measured supply of donors, the current limitations to medical technology mean that patients must rely on drug regimens and machines in order to survive. Fortunately, a new method of addressing organ shortages seems to be on the rise.
Enter 3D printing
Invented in the 1980s by an engineer named Chuck Hull, 3D printing covers a range of processing techniques that translates and outputs digital information into three-dimensional (3D) objects. Traditionally referred to as “Additive Manufacturing” or AM, 3D printing builds an item piece by piece instead of chipping away or removing material, as is the case with earlier “subtractive” manufacturing methods.
The object is created via a computer-aided design (CAD) program which utilizes geometric surfaces. CAD files contain information as to the x-y-z coordinates of a build in order to output a solid object. 3D printing encompasses several different types of technologies, including:
- Stereolithography (SLA): Sterolithography utilizes a vat of photo-sensitive resin which is then cured layer by layer with ultraviolet light.
- Fused Deposition Modeling (FDM): FDM works whereby an extruder lays down lines of material, usually in cross-hatched patterns from the bottom up.
- Powder Bed: These types of 3D printing direct a laser throughout a bed of powdered material to create a solid object.
Because of 3D printing’s high capability for mass production as well as specialization, the technology sees many applications and more are becoming possible as companies refine their 3D printers. 3D printing is changing many industries, especially that of healthcare and medical, which often require a high level of accuracy as well as bespoke solutions for individual patients.
3D printers can create complex geometric structures with accuracy down to the micrometer. These capabilities make them the ideal technology for many medical procedures. 3D printers serve as an assist to surgeons who can create exact replicas of a patient’s body part with a 3D scan. These models are then used to plan and practice complicated surgeries.
Scientists have also been able to create some tissues by depositing medical-grade, biological material (such as collagen or chitosan) into a pattern, which can be modified according to CT and MRI scans of the patient’s body. Connective tissues such as cartilage and bone have been created through 3D printing, such as the 3D printed knee meniscus created by Columbia University.
With applications already in place in the medical field, many research teams and academic organizations have been researching how best to use 3D printing technology to address the problem of organ shortages. In a race for discovering best practices for viable organs, physicians and scientists are completing a vast array of research using human cells and 3D printed scaffolds to grow new organs that will be accepted by the human body.
Some biomedical 3D printing teams have been working with gels utilizing sugar or alginate. The printer lays down a 3D matrix, or scaffold, in which is then deposited with living cells, such as embryonic stem cells, which have the ability to become any type of cell in the body. The cells “eat” up the glucose or alginate gel, eventually taking on the shape of the 3D scaffold. Another method is that of hydrogels, which support the sample before melting away. These techniques are popular method for attempting to construct a three-dimensional organ that is an effective replacement of the patient’s own organ.
Scientists at Princeton University have created bionic ears using an amalgamation of calf cells and silver nanoparticles. The calf cells formed cartilage in the shape of a human ear, while the metal was interwoven in the build to create an antennae component.
Other scientists at Wake Forest University have been working on creating skin grafts for use in reconstructive surgery for soldiers wounded overseas.
Organovo has developed in vitro human kidney tissue after developing proprietary tissue for drug testing. The kidney was composed of human cells and survived for two weeks; the sample exhibited renal proximal tubular epithelial cells, renal fibroblasts, endothelial cells, and microvascular structures, which have been a challenge for previous teams to grow in engineered human tissue.
The difficulty of creating a complex adult organ like a heart or a kidney relies on refining vascularization, whereby blood is supplied to the organ and circulated to the rest of the body.
Full-size functional human organs are the dream of this disruptive technology; companies such as Organovo with its NovaGen bioprinter are the chosen tools for research and development. Johns Hopkins University made a 3D printed ear in 2015, while the Cleveland Clinic recently created a model liver for potential transplant.
While 3D printing organs for adult humans may take some time, the future looks promising. It’s likely we will see this process being safely implemented in surgery in our lifetimes.
Imagine the possibilities: instead of waiting months or even years for a much needed organ transplant, a medical team could make one according to the exact specifications of your system, in a fraction of the time. Organs are very high in demand today, but creating them on a case-by-case basis is the hope for the future.