Colorado State University is engineering tissue in a laboratory that can replace the use of animals in research. The Tissue Engineering Laboratory, established this academic year in the College of Veterinary Medicine and Biomedical Sciences, creates tissue from a combination of cells, materials and biochemicals that model living biological systems. The model tissue replaces live animals in the initial phases of many biological studies, reducing the number of animals needed for use in research.
"As a researcher, I want to understand tissue cellular responses and develop a greater capacity to mitigate or prevent damage," said Dr. Tom Eurell, veterinarian and expert in toxicology and immunology and director of the laboratory. "As a veterinarian, I want to minimize or eliminate painful experiments in animals. Tissue engineering allows me to do both.
"It is impossible with current technology to model whole systems of human or animal response and repair, and to model systemic inflammation," Eurell said. "But we have the technology to be smarter about what we use and to refine our techniques for the benefit of both animals and humans."
For example, Eurell engineers artificial corneas. He uses corneas from already euthanized animals or human corneas donated to research as a "starter" to engineer more corneas by isolating stem cells from the corneas and growing new tissue in the lab. Each donated cornea can be used to create 20 to 25 artificial corneas. This reduces the need for live animals to test a variety of products and chemicals for eye irritants.
"We are trying to understand the best ways to help the eye repair itself following injury, and there are many things we don’t know about this process," Eurell said. "For instance, we are interested in determining what happens to cornea cells after they have been exposed to lasers from therapeutic procedures such as LASIK or accidental exposure such as exposure to lasers during manufacturing processes. Engineering cornea tissue allows us to add one more tool to research rather than testing an initial concept on animals. We can use engineered tissues to assess the concept and determine from those results whether or not we should even move on to the next steps in research."
Eurell is working with human corneas donated from local surgery centers that do human corneal transplants to develop multiple corneas for research within the lab. These engineered corneas are used in the lab to study how the cornea actually functions when healing after injuries. By developing these models, Eurell can better understand how cells interact during the healing process.
In addition to researching cornea repair, Eurell also works with colleagues at Colorado State to research how lung cells react to airborne particles of different sizes, the use of nanotechnology to address health issues, proteins within cells, and substrate and cell interactions.
Tissue engineering has been used for some time to repair or replace hard tissues, such as bones, in human and veterinary patients. More recent developments in soft tissue research, including corneas, skin and muscle, can greatly reduce the number of animals used to test compounds and research tissue repair after trauma.