It has been widely recognized that animal models for testing drugs and other medical treatments have several serious flaws. In some cases, the
It has been widely recognized that animal models for testing drugs and other medical treatments have several serious flaws. In some cases, these methods are unethical and cruel. Moreover, these studies are not always able to accurately predict human physiology. Many of these studies come with extensive costs, which means some drugs might never make it to the testing phase.
Researchers around the globe have been working on developing miniature human organs that could potentially replace animal testing and speed up drug trials.
Their experiments show that this emerging nascent technology can often predict the body’s response to drugs and diseases without using living subjects. The pharmaceutical industry is expressing interest in this budding health technology, which is helping to fuel its innovation.
Organ-on-a-Chip for Drug Testing
An organ-on-a-chip is a device created using microchip manufacturing methods. It contains continuously perfused chambers lined by living human cells. The size of a small computer memory stick, this device mimics the biology and functions of real organs and is an upgrade on the existing systems in use today (such as living cells grown in a petri dish).
Scientists have already developed different organs-on-chips: the lung, heart, intestine, and liver. Lung-on-a-chip, for example, contains both pulmonary and capillary cells with one side exposed to a blood-like medium and the other to air.
This provides scientists with insight into the part of the lung where gas exchange happens. This is the area where pulmonary problems such as infections and cancer often occur. Lung-on-a-chip is flexible, so it stretches and contracts much like a human lung – replicating the function of the living organ.
Organs-on-chips technology originates from the labs of Wyss Institute for Biologically Inspired Engineering at Harvard University. Some commercial companies are now manufacturing chips that replicate a diseased organ as well. Others are focusing on the way drugs – both already approved and newly developed – behave in these devices in comparison to the human body. As pharmaceutical companies agree that investing in chip technology is a worthy pursuit, further investment and subsequent refinements will make organs-on-chips even more useful in the future.
Last year, Emulate, Inc. announced a research collaboration with Johnson & Johnson and the Wyss Institute to evaluate their thrombosis-on-a-chip platform that could potentially be used to test drugs that are known to cause blood clots. The chip models different factors that could contribute to the development of a blood clot. If successful, this technology could be used in clinical drug trials to minimize the risk caused by some drugs — such as immuno-therapeutics and oncology drugs – known for possible side effects connected with blood clotting.
Recent advancements in growing rudimentary organs from stem cells could also support organ-on-a-chip technology.
Experiments show that human stem cells can be programmed to produce different types of tissue. While it will take some time before this technique can be used to grow personalized organs for transplant patients, it can already be applied to grow human tissue for organ-on-a-chip models.
Will There Soon Be Human-on-a-Chip?
Scientists at the Wyss Institute are now working on an ambitious project: They are looking into linking different organs-on-chips to create a replica of the entire human body. This could aid drug trials in an unparalleled way. Multiple in vitro “subjects” could be tested and analyzed for their response to a certain drug in a short period of time.
Homo chippiens, as the model has been dubbed humorously, has also been explored by the US Environmental Protection Agency as an alternative model for studying the effects of environmental toxins, such as the effects dioxin and Bisphenol A (BPA) have on the human liver.
At the moment, almost any new drug still needs to undergo a lengthy clinical trial as well as be tested on humans first before it hits the market. The development of miniature human organs might make the development process shorter by skipping a portion of a new drug’s trial protocol. Some experts, however, warn that chips cannot capture the full complexity of a human organ and that this technology has limitations that will need to be addressed before they become useful as true alternatives to real organs.