Future looks bright
Anna Wynn, business development manager, Instron TERM, provides an insight into the future of healthcare and tissue engineered medical devices
Tissue Engineering and Regenerative Medicine (TERM) are dedicated to creating new tissue-engineered medical devices that replace and/or enhance tissue function that has been impaired by disease, injury, or age. Tissue-engineered medical devices are a combination of cells, scaffolds (materials on which to grow the cells) grown to produce 3D tissues that are similar to native tissue.
Today’s health care system is focused on treating the conditions of disease and moderating the symptoms; TERM is focused on repairing the damaged tissue. This paradigm shift has the potential to drastically improve health care, as well as provide huge economic savings. As an example, the annual direct costs of organ replacements are currently $350 billion worldwide or about 8% of global health care spending. These costs include clinical therapies to keep patients alive, implanted devices, and organ transplants. Despite the astronomical cost, only a fraction of patients waiting for organs are receiving them. According to the Organ Procurement & Transplantation Network (6/19/14), there are 125,695 organs on the waiting list while only 3,407 have been recovered this year for transplantation with a 50% mean success rate.
In the future, tissue-engineered therapies could cure some of these diseases and stop patients from relying on organ donors. Patients could receive the healthy tissue they need – tissues made of their own cells to cure their conditions and end treatment. These therapies eliminate immune responses.
Without a change, health care costs will continue to rise. In fact, research indicates that costs will double by the year 2040, reaching heights that the world cannot sustain.
Example: Cardiovascular Disease
The World Health Organization recognizes cardiovascular disease (CVD) as today's largest single contributor to global mortality and they expect that it will continue to dominate mortality trends in the future. Data indicates that there will be about 20 million CVD deaths in 2015, accounting for 30% of all deaths worldwide.
Contributing to these numbers are coronary disease and congenital heart defects. Both of these could be treated with tissue-engineered solutions: coronary artery bypass grafts and tissue-engineered heart valves. Tissue-engineered solutions are especially relevant to pediatric patients, providing a healthy replacement that grows with the child. Congenital heart defects are structural problems with the heart present at birth. They result when a mishap occurs during heart development soon after conception and often before the mother is aware that she is pregnant. Defects range in severity from simple problems, such as "holes" between chambers of the heart, to very severe malformations, such as complete absence of one or more chambers or valves. Out of 1,000 births, nine babies will have some form of congenital heart disorder, most of which are mild. The mechanical devices currently used in these young patients require repetitive surgery to match the size of the device to the fast growing patient. However, if a young child receives a tissue-engineered heart valve, it is a living tissue that grows with the child, eliminating the need for future surgeries. Furthermore, the device is generated using the patient’s own cells removing the risk of rejection or complicated immune responses.
New tools are being used by researchers around the world to develop tissue-engineered devices. One of these tools is a bioreactor, which is designed to provide a controlled environment for growing the tissue outside of the body. It can use mechanical means to influence biological processes. In tissue engineering, bioreactors can be used to aid in the in vitro development of new tissue by providing biochemical and physical regulatory signals to cells and encouraging them to undergo differentiation and/or to produce extracellular matrix prior to in vivo implantation. In the case of heart valves, the mechanical stimulation (pressure, flow) mimics a heartbeat to condition the valve and promote cell proliferation and differentiation. The combined mechanical, biological, and chemical cues provide instructions to the cells to tell them what to be; this ensures that the tissue-engineered heart valve will behave the same as a native valve.
Bioreactors are also being used in pharmaceutical research to treat cardiovascular disease. The ability of these tools to mimic the native physiology allows researchers to study the effects of new pharmaceuticals in a controlled environment on the bench top. Previously, these conditions could only be achieved in an animal model or clinical trial.
Today, researchers hope that tissue engineering research can combat the future of increasing CVD deaths worldwide.