Organs-on-chip can provide valuable insights into normal organ function and disease pathophysiology, helping to predict the safety and efficacy of new drugs, .
Usually, researchers use these tools in combination with traditional preclinical cell culture methods and in vivo animal studies. But could they replace animal testing for good?
This article talks about organs-on-a-chip as alternatives to animal testing in the pharma and biotech industries. We also present Cellix's microfluidic solutions to organ-on-chip models to get you started.
Replacing Animal Testing – Why is it Necessary?
Researchers have used animal models for decades to study human diseases and treatments. And the number of animals used in research is increasing dramatically due to medical technology advancements, .
Animal experimentation is an old debate in the scientific community. The main argument against it concerns the human right to cause animal suffering and distress. Because of that, many governments created laws to control the use and minimize pain during animal experimentation, .
But besides ethical concerns, animal testing has a few more disadvantages:
It requires skilled/trained professionals
Protocols are time-consuming and expensive
High cost involved in breeding and housing of the animals
Animal models are often limited in their ability to mimic human conditions
Animal Testing Alternatives
Scientists have become used to working with animal models, mainly because it's a consolidated method. But some of the drawbacks mentioned here are making them think of alternatives, [2, 3].
Today's primary strategy is to apply the 3 Rs rule (reduce, refine, and replace). The 3 Rs is about using the minimum number of animals to answer your research question (reduce), planning the experiments carefully to avoid pain and distress (refine), and finally, using alternative methodologies and lower organisms when possible (replace).
Animal replacement can be absolute or relative. Relative replacement still uses animals that are not submitted to any kind of distress during the experiment, while absolute replacement eliminates animal use completely.
Scientists are developing alternatives for drug and chemical testing, and the perspectives are promising. Examples are computer models, cell and tissue cultures, and alternative organisms, .
Software can generate simulations to predict possible biological or toxic effects of drug candidates. Cell culture can be used for preliminary screening of molecules to check their efficacy and toxicity. And finally, invertebrates, lower vertebrates, or microorganisms could replace higher vertebrate models like rats, guinea pigs, dogs, and monkeys, .
Next, we'll give more detail about organ-on-chips technology as an alternative to animal models.
Organs-on-chip or tissue chips are bioengineered microdevices that simulate the functioning of human organs and tissues. These devices can be the size of a USB drive or can reflect multiple linked organs within a standard 96-well laboratory plate, .
Main characteristics of Organs-on-chip are:
3D nature and tissue arrangements on the platform
Presence of multiple cell types to ensure physiological balance
Presence of relevant biomechanical forces
These biomechanical forces can be created when researchers use microfluidic channels to deliver and remove cell culture media and remove cell metabolites and detritus.
Organ-on-a-chip's major advantage is controlling the biochemical and cellular environment to model in-vivo responses. It also allows tissue perfusion using microfluidic channels that act as engineered vessels, bringing nutrients and fluidic flow to cells. Moreover, researchers can incorporate sensors to monitor the cell's health and activity in real-time, .
Organs-on-chip offers many possibilities for R&D and basic biomedical research. Examples of applications are:
Toxicity assessment of potential drug candidates
Studying diseases mechanisms in vitro
Testing the effects of therapeutic interventions
Creating patient-derived tumours on-chip to optimise personalised treatment
Modelling rare diseases to better understand these pathologies
Building a body-on-a-chip has the potential to model complex organ-organ interactions and predict drug pharmacokinetics, pharmacodynamics, and physiological profile. It’s exciting but quite a complex model to produce. Most researchers are currently developing simpler models focused on one organ. Organs-on-chip can effectively mimic human organs and are commercially available at a reasonable cost. They can provide better in vivo models and will reduce the need for animal testing.
How can you get started?
Cellix’s 4U Pulse-Free Microfluidic Pressure Pump & Biochips
If you want to start running experiments with organs-on-chip, Cellix can help you get started. We can provide you with a complete set-up (organ-on-chip kit) or just the components you need.
The basic set-up for organs-on-chip experiments include:
Microfluidic chip: designed to mimic the physiological conditions and mechanical forces that cells experience in vivo. Some researchers are developing their own organ-on-chips but if not, we can offer you the Vena8 Endothelial+ chip to get you started.
Microfluidic pumps: to deliver culture media to grow your cells in the chip. Our 4U 4-channel Microfluidic Pump is ideal for this type of experiment. This precision pressure pump has a stable and accurate flow rate and enables independent control of 4 different channels, controlling both pressure and flow. You can easily program your own flow profile and manage all the pump features.
Flow sensors: to give you feedback on the flow control and keep your experiments on track.
Sample reservoir and other accessories: hold the culture media to feed your cells, deliver drugs, or flow a cell suspension through the organ-on-a-chip system.