TERMIS – Tissue Engineering & Regenerative Medicine International Society – hosts an annual conference which is often found to be eye-opening by many people in the field of tissue engineering as it showcases the field’s latest technologies and groundbreaking research. This year, TERMIS-Americas is hosted by The Parker H. Petit Institute for Bioengineering and Bioscience at Georgia Tech with Dr. Robert Guldberg as the Conference Chair and Dr. Todd McDevitt as the Scientific Program Chair. According to McDevitt, the scientific program is “based upon the fundamental principles, emerging strategies and applications of the latest advances in tissue engineering and regenerative medicine” along with “workshops and symposia on clinical and commercial translation.” There are 200 oral presentations and 400 poster presentations. Many of the presenters hail from foreign countries such as Japan and the United Kingdom. Since tissue engineering is a multi-disciplinary field, project creation involves everything from mechanical engineering to nanotechnology.
One important part of tissue engineering is testing of the mechanical properties of the engineered tissues such as bone, scaffolds and hydrogels, and soft tissues like skin, muscle, and arteries. Bose, a company mainly known for its audio system, has an Electroforce® System group that manufactures devices for this purpose. One of its displayed devices incorporates the electromagnetic technology Bose uses for audio products as a motor to stimulate tissue-engineered constructs. Depending on the tissue, cells respond to different types of mechanical loading such as tension in the case of tendon and ligament and compression in the case of cartilage. The motor technology is able to apply a combination of such forces to tissues, and output the waveform of the force. When asked about her expectation for TERMIS, Stefanie Biechler, PhD, who works as a senior applications engineer for Bose, commented that TERMIS is a good chance to network with customers and learn more about their needs so that Bose can focus its efforts appropriately. She also emphasizes the career opportunities Bose has to offer for various types of engineers.
Other than showcasing tissue-testing devices, TERMIS also presents companies that focus on regenerating organs. One such company is Harvard Apparatus Regenerative Technology, which makes a bioreactor called Hollow Organ Bioreactor that generates tissue-engineered tracheas.
The first step of regenerating a trachea is molding. First, a CAT scan of the patient’s trachea is taken and a metal model is made according to the scan. Using electrospinning technology, a solution of dissolved polymer is shot from a syringe onto the metal mandrel. Then, the metal mandrel is charged so that the solution evaporates, leaving fibers with diameter in nano-scale coating the mandrel, and rings made of PET material are added onto the fiber to mimic the function of cartilage in the human trachea, giving the fiber mold stability and flexibility at the same time. After another coat of polymer fiber is added, the molding process is finished.
The next step is coating the fiber with stem cells. These stem cells can be prompted to differentiate through various means. For example, the inside of the trachea becomes an endothelial layer. Then, the differentiated stem cells are inoculated onto the trachea scaffold using a syringe. Before implantation, the trachea is put into a bioreactor, which is incubated for two and a half days. The bioreactor provides physical stimuli – partially immersing the trachea in culture medium while rotating it to give it both liquid and air – and chemical stimuli – cytokines and growth factors. After implantation, it takes about seven to ten days for the cells to continue to grow before they become confluent. The Hollow Organ Bioreactor opens a new method of trachea acquisition and helps save many lives from the hands of tracheal cancer.
In addition to the regeneration of tissues, creating a support system for healthy tissue function is also part of the research effort. One such example is the creation of a biomaterial to treat age-related macular degeneration (AMD) by L.A. Turner and Erin M. Baggaley from the School of Materials in University of Manchester in United Kingdom. According to Turner, AMD, which is caused by damage or loss of the retinal pigment epithelium (RPE), is the leading cause of blindness in industrialized countries, and, by the year 2020, is set to affect over 6 million people. The transplantation of RPE in humans is as of yet unsuccessful due to the bad degradation of the Bruch’s membrane (BM) underlying RPE; BM serves as a filtration net for nutrients and wastes. Turner and Baggaley have created an artificial membrane mimicking BM with pores of 2 µm in diameter using PDMS, a type of organosilicon, The membrane is treated with UV/Ozone to optimize its biocompatibility and suitability for RPE growth – the treatment makes the membrane hydrophilic. This product is patented, and the next step is to find a way to transplant it into the eye. Turner’s motivation for the project stems from the fact that both of her grandparents went blind due to AMD.
TERMIS will be a valuable experience for anyone because, as tissue engineering and regenerative medicine take on a bigger role in healthcare, platforms like TERMIS that enable the exchange of information become more important. TERMIS fosters growth in the industry, and shares what it takes to publish a study or develop a device.