"Person on a Chip"

Being placed on an organ transplant list is a nightmare for patients that are racing the clock to prevent premature death. Each second ticking by is another moment of terror for them. But the fear of finding hearts, livers, and, potentially, other organs in time may be diminished in a few years. Around the world research groups, as well as a team from University of Toronto, are trying to find ways to grow tissues under lab conditions that “mimic a real person’s body” (Mole, 2016). At the University of Toronto, chemical engineer Milica Radisic, graduate student Boyang Zhang and the rest of their research group have created a method in growing these tissues.

The team has created the AngioChip, “a fully three-dimensional structure complete” with a vascular system. The scaffold is made out of a polymer that is both biocompatible and biodegradable. The polymer is then used, in thin layers, to create the structure of the AngioChip. The layers, resembling a computer chip (hence the name), are stacked into a three-dimensional structure of synthetic blood vessels by using UV light to cross-link the polymer and bond it to the previous layer. The finished structure is submerged in a liquid containing living cells of the organ they want to build. These cells then attach to the inside and outside channels of the scaffold and begin growing (Irving, 2016).

A close-up of the AngioChip.

Using this method, the team had built model version of both the liver and heart tissues that are functionally similar to the real thing. The model liver “actually produced urea and metabolized drugs.” The group has also injected white blood cells into the connected heart and liver apparatus and observed that the blood cells moved, as they would have in a human. Other than the transplant possibilities for the models, they have great potential in the field of pharmaceutical testing. Instead of animal testing and controlled clinical trials, the lab-grown human tissues would provide a realistic model to test drugs. The tissues can also be used to “validate the effectiveness of current drugs” and screen a lot of chemical compounds to discover new drugs (Univ. of Toronto, 2016).

When seeded with heart cells, the flexible polymer scaffold contracts with a regular rhythm, just like real heart tissue. Credit: Boyang Zhang

Even though this is a huge advancement in medical technology, there are still many hurdles to overcome. Each AngioChip is made by hand; if the chip is to be used industrially, a thought-out machine manufacturing process needs to be created to produce mass quantities in a short period of time (Univ. of Toronto, 2016).

As a chemical engineering student, I am intrigued about the applications chemical engineering has in the medical field. I desire to pursue a career that has a focus on medicine and this article displayed a use chemical engineering has in creating a potentially life saving device. I am very excited about this tissue engineering advancement since the same process can be used to create other major vascular organs of the human body. This will immensely benefit the patients that are waiting for an organ donor match, which is the major drawback of organ donation. However, the tissue cultures for the AngioChip can be engineered to be genetically identical to the intended host, reducing the risk of organ rejection (Mole, 2016). While there is still manufacturing kinks to work out, the huge benefits that can come from this invention will revitalize organ donation. However, there may be social consequences to this: will people be more likely to practice bad habits, such as smoking and excessive alcohol intake, since there will be a viable organ essentially waiting for them?

References:

Irving, Tyler. "'Person-on-a-chip' - U of T Engineers Create Lab-grown Heart and Liver Tissue for Drug Testing and More - U of T Engineering News." U of T Engineering News. 07 Mar. 2016. Web.

Mole, Beth. "Creation of Mini-organs Follows Mini-brains." Arstechnica. N.p., 9 Mar. 2016. Web.

University of Toronto Faculty of Applied Science & Engineering. "'Person-on-a-chip': Engineers grow 3-D heart, liver tissues for better drug testing." ScienceDaily. ScienceDaily, 7 March 2016.