Organ On Chip: Putting the Human Body on a Microchip

Introduction

For decades, biomedical research has had a repeated problem on clinical tests.

If a newly discovered drug successfully cures a disease in an animal model, for example, a mouse, it should have a similar treatment effect, but when it enters human clinical trials, it fails to deliver any effects .

How come? The simple explanation is that animals are simply not humans. Despite sharing a similar genome of 85%, Mice possess several characteristics which we don't such as hyper-active metabolisms and do not naturally develop complex human illnesses like Alzheimer's or human-style cancers. Due to this, scientists have had to genetically "fake" these diseases in animals just to run tests, we end up with experimental drugs that perfectly cure the lab rat, but completely fail when up against our complicated human system.

To break this frustrating cycle and bridge the gap between the lab and the patient, researchers are turning to a groundbreaking solution that sounds like science fiction: Organs-on-Chip. Instead of relying on flawed animal models or flat, static Petri dishes, this technology puts living, breathing human biology directly onto a polymer microchip.

What are Organs-on-Chips?

Organ-on-chip is a clear in-vitro microfluidic device, usually as small as a USB stick.  Inside the chip consists of hollow micro-channels lined with living human cells and tissues from different organs such as the brain, heart, and the lungs.

Unlike a petri dish, in which cells are rested or adhered in the dish, these devices rely on microfluidics, which manipulates microliter amounts of fluids of around 10⁻⁹ to 10⁻¹⁸ liters. This allows the chip to expose human cells to directional fluids in motion by mimicking the natural mechanical forces of the human environment where nutrients continuously flow in, while cellular waste flows out.

Researchers can gain more accurate control over our body’s complex biological parameters which are impossible to replicate in standard 2D Petri dishes. This includes controlling concentration gradients,and recreating tissue-to-tissue interactions where different parts of an organ interact.

Why It Matters

To develop a successful drug, it takes an average of at least 10-15 years, and a high cost of 1 billion USD. While taking up so much time and money, 90% of drug candidates fail to meet its standards, most due to unforeseen toxicity such as hepatotoxic effects towards humans or there was only minimal efficacy which had been missed out.

A massive recent study evaluating the 870 Liver-Chips. Modeling the human liver in the lab is difficult as traditional cell cultures failed to simulate the entire microenvironment, which is essential for the cells to survive and maintain their metabolic functions.

The 870 Liver-Chips were tested against a set of 27 different small-molecule drugs to prove exactly how transformative this technology could be, these were the results they found:

1. The Liver-Chip demonstrated an 87% sensitivity and a perfect 100% specificity in predicting drug-induced liver injury while compared to 3D hepatic spheroids (clusters of liver cells), which only achieved a 47% sensitivity when predicting toxicities for the exact same drug set.

   
   

2. The Chip successfully detected an apoptotic (cell-killing) toxicity of the antibiotic trovafloxacin, which typically miss unless researchers co-administer an inflammatory stimulant.

The study also calculated that routine adoption of Liver-Chips would generate an estimated 3 billion USD annually for the pharmaceutical industry through increased R&D productivity and avoided clinical trial failures.

Driven by the undeniable precision of the technology and its ability to drastically reduce drug attrition, widespread acceptance of Organ-Chips could help manufacturers bring safer, more effective medicines to the market in less time and at lower costs.

Advantages Over Traditional Models

Features	Organs-on-Chips	Animal Models	2D Petri Dishes
Human relevance	High (Uses human cells)	Low	Moderate (lacks microenvironment)
Mechanical simulation	Yes, microfluidics	Yes (whole organism)	No (static environment)
Ethical concerns	None	High	None
Speed & Precision	High	Low (slower development)	High

Applications in Modern Medicine

Drug Discovery and Toxicology

●      Pharmaceutical companies can test thousands of new compounds on human liver or kidney chips to identify toxic side effects before a drug ever reaches expensive human trials.

Personalized Medicine

●      Doctors can use a patient's own stem cells to populate an organ-chip. If a patient has cancer, oncologists can test a dozen different chemotherapy drugs on the patient's customized chip to see which specific treatment works best for them.

Disease Modeling

●      Scientists can infect an organ-chip with a pathogen (SARS-CoV-2) to observe exactly how human tissues react in real-time.

Challenges and Limitations

Despite it being revolutionary, Organs-on-Chips technology is still evolving and improving, such as:

1. Manufacturing complexity: Hard to create standardized and highly scalable chips for mass commercial production.

2. Immune System Integration: Accurately replicating the full, systemic human immune response inside a microfluidic device is still an ongoing engineering challenge.

Conclusion

Organs-on-Chips represent a massive technological shift in biomedical sciences. By combining micro-engineering with the human body, this technology promises to reduce  our reliance on animal testing while making drug development safer, faster and more accurate. As researchers continue to connect these chips together, we are steadily moving toward a future where the most accurate model for human health is no longer an animal model, but a microchip.

Citation

Ewart, L., Apostolou, A., Briggs, S. A., Carman, C. V., Chaff, J. T., Heng, A. R., Jadalannagari, S., Janardhanan, J., Jang, K.-J., Joshipura, S. R., Kadam, M. M., Kanellias, M., Kujala, V. J., Kulkarni, G., Le, C. Y., Lucchesi, C., Manatakis, D. V., Maniar, K. K., Quinn, M. E., & Ravan, J. S. (2022). Performance assessment and economic analysis of a human Liver-Chip for predictive toxicology. Communications Medicine, 2(1), 1–16.

Mckean, N. E., Handley, R. R., & Snell, R. G. (2021). A Review of the Current Mammalian Models of Alzheimer’s Disease and Challenges That Need to Be Overcome. International Journal of Molecular Sciences, 22(23), 13168.

Mullard, A. (2016). Parsing clinical success rates. Nature Reviews Drug Discovery, 15(7), 447–447.

National Human Genome Research Institute. (2010, July 23). Why Mouse Matters. Genome.gov.

Singh, D., Mathur, A., Arora, S., Roy, S., & Mahindroo, N. (2022). Journey of organ on a chip technology and its role in future healthcare scenario. Applied Surface Science Advances, 9(100246), 100246.

Team, E. (2021, February 5). Microfluidics: A general overview of microfluidics. Elveflow; Elvesys.

Wouters, O. J., McKee, M., & Luyten, J. (2020). Estimated Research and Development Investment Needed to Bring a New Medicine to Market, 2009-2018. JAMA, 323(9), 844.

---

This article was prepared by Chin Yu Xuan (Taylor's University)

---