A petri dish for the 21st Century has been developed which promises to revolutionise research into diseases.
Traditionally, biological studies were and still are done in petri dishes, where specific types of cells are grown on a flat surface.
They have helped many of the medical advances made since the 1950s, including the polio vaccine, have originated in petri dishes.
Yet these two-dimensional environments do not accurately represent the native three-dimensional environments of human cells, and can in fact lead to misleading information and failures of drugs in clinical trials.
So scientists at the University of Cambridge and colleagues from France, Greece and Saudi Arabia developed a three-dimensional ‘organ on a chip.’
This will enables real-time continuous monitoring of cells, and could be used to develop new treatments for disease while reducing the number of animals used in research.
The device which looks like a plumbing switch valve incorporates cells inside a 3D transistor made from a soft sponge-like material inspired by native tissue structure, gives scientists the ability to study cells and tissues in new ways.
By enabling cells to grow in three dimensions, the device more accurately mimics the way that cells grow in the body.
It could also be modified to generate multiple types of organs – a liver on a chip or a heart on a chip, for example – ultimately leading to a body on a chip which would simulate how various treatments affect the body as whole.
Senior author Fellow and College Lecturer Dr Róisín Owens from Cambridge’s Department of Chemical Engineering and Biotechnology said: “Two-dimensional cell models have served the scientific community well, but we now need to move to three-dimensional cell models in order to develop the next generation of therapies.”
First author postdoctoral researcher Dr Charalampos Pitsalidis added: “Three-dimensional cell cultures can help us identify new treatments and know which ones to avoid, if we can accurately monitor them.”
3D cell and tissue cultures are an emerging field of biomedical research, enabling scientists to study the physiology of human organs and tissues in ways that have not been possible before.
While these 3D cultures can be generated, technology that accurately assesses their functionality in real time has not been well-developed.
Dr Owens explained: “The majority of the cells in our body communicate with each other by electrical signals, so in order to monitor cell cultures in the lab, we need to attach electrodes to them.
“However, electrodes are pretty clunky and difficult to attach to cell cultures, so we decided to turn the whole thing on its head and put the cells inside the electrode.”
The device is based on a ‘scaffold’ of a conducting polymer sponge, configured into an electrochemical transistor.
The cells are grown within the scaffold and the entire device is then placed inside a plastic tube through which the necessary nutrients for the cells can flow.
The use of the soft, sponge electrode instead of a traditional rigid metal electrode provides a more natural environment for cells, and is key to the success of organ on chip technology in predicting the response of an organ to different stimuli.
Other organ on a chip devices need to be completely taken apart in order to monitor the function of the cells, but since the Cambridge-led design allows for real-time continuous monitoring, it is possible to carry out longer-term experiments on the effects of various diseases and potential treatments.
Dr Pitsalidis concluded: “With this system, we can monitor the growth of the tissue, and its health in response to external drugs or toxins
“Apart from toxicology testing, we can also induce a particular disease in the tissue, and study the key mechanisms involved in that disease or discover the right treatments.”
The study was published in the journal Science Advances, and researchers have filed a patent for the device in France.