Artificial capillary systems are useful for growing organs for transplants, yet the creation and manipulation of these organs might be a little tricky. An assistant professor of mechanical engineering, Leon Bellan, alongside his team at Vanderbilt University, has successfully introduced a technique to create three-dimensional artificial capillary systems. In an effort to create new artificial capillary systems, Professor Bellan was inspired by cotton candy machines.
Professor Bellan has been tinkering with cotton candy machines for several years, getting them to spin out networks of tiny threads, which are similar to the patterns formed by capillaries. According to an article published on February 4 by the Advanced Healthcare Material journal, Bellan reported a success in using this rare technique to produce three-dimensional artificial capillary systems. An incredible improvement from current methods, given that the system can keep living cells viable and functional for over a week.
But constructing such a network of capillaries to nourish the thick tissue of a solid organ such as kidneys or livers has been an ongoing challenge, according to Bellan and his team at Vanderbilt University. Artificial organs don’t have the capacity to adapt as well as a naturally harvested organ with a high metabolic requirement.
“Some people in the field think this approach is a little crazy,” stated Professor Bellan,
Scientists and engineering researchers, Bellan included, are currently focusing their efforts on a variety of material similar to hair gel. As this water-based gels, called hydro gels, can support the cells within three-dimensional artificial organs without harming the human body. The gel needs to be solid enough to transport liquids as well as it needs to be porous enough to allow oxygen, waste and nutrients to diffuse through the capillaries.
Researchers now can build capillaries by layering cells in a gel, thus, allowing them to grow. Yet, it’s a challenging process as sometimes the cells die before the network is fully formed, but that doesn’t discourage scientists, Professor Bellan included.
Bellan’s new method consists on using a material known as PNIPAM, a polymer that is insoluble at temperatures above 32 degrees. The way it works is quite simple, he spins the PNIPAM to make a network, and then he mixes gelatin in water and adds human cells to the gelatin. The resulting mixture of gelatin and human cells is then poured over the PNIPAM structure and cooled down.
“Our goal is to create a basic toolbox that will allow other researchers to use this simple, low-cost approach to create the artificial vasculature needed to sustain artificial organs,” Profesor Bellan added.