Author: Clelia Introna
How can we study the vitalest and most complex organ of our body, the brain?
What if we want to investigate something we cannot access in human being and whose complexity cannot be fully recapitulated by animal models? Easy: WE NEED TO BUILD A NEW BRAIN.
To build something so tangled, we have to start from the simplest and tiniest part that makes it up: neuron and its connection. In the little box of our cranium, tens of billions of neurons of different types speak to each other through connections called synapses, using chemical and electrical signals to transmit any type of information, from thought to senses, from emotions to movements. In the little box of our cranium, 100 trillion of connections, 1000 times more than the stars in our galaxy, shape the most complex network that exists, more complex than any kind of powerful computer we can build, and we scientist want to unravel its mistery and to understand how and why sometimes this network fails.
So, how to reproduce this?
The bright side we have is that neurons behave in the same way when they are inside and outside the brain, so that we can grow them in vitro and reconstruct the interactions among different brain regions, to study the dysfunctions that lead to neurodegenerative diseases.
To reproduce the interactions between the different regions of the brain, we can generate what is called a BRAIN-ON-A-CHIP, an in vitro micrometric device, where cell body of a neuron and its projections can be grown separated, allowing the latter to cross 10-6 metre -sized channels . Such compartmentalization makes possible to grow together cell types that form distinct brain regions to study the characteristics of their communication.
Which are the main advantages of a Brain-on-a-chip?
First of all, we can reproduce the complexity of a human neuronal network without taking a whole brain off from a human being, that also sounds quite unsafe, so that we can study which are the mechanisms of neurodegenerative diseases.
Also It makes possible to test several drugs at time, on the same brain-on-a-chip model, cutting the expensive costs and long time of developing and testing new compounds.
Interestingly, it also makes possible to recreate “Your brain-on-a-chip, taking cells directly from a patient and grow his own neurons on the device, with his genes, his pathology, to identify the optimal patient-specific therapy. In a not-so-far future, the patient will go his doctor, and biopsy of his cells he will obtain a tailor-made treatment, that can increase the effectiveness of the treatments and minimize the side reactions. This great scenario, is known as Personalized Medicine and can made be real thanks to the use of another great scientific breakthrough that our researcher use, that are the Induced Pluripotent Stem Cells.
References and links:
- Image from: Zhao Y et al., "Multiscale brain research on a microfluidic chip". Lab Chip.
- Bang S, Jeong S, Choi N, Kim HN. Brain-on-a-chip: A history of development and future perspective. Biomicrofluidics. 2019 Oct 8;13(5):051301. doi: 10.1063/1.5120555. PMID: 31616534; PMCID: PMC67
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- VK, Kalsan M, Kumar N, Saini A, Chandra R. Induced pluripotent stem cells: applications in regenerative medicine, disease modeling, and drug discovery. Front Cell Dev Biol. 2015 Feb 2;3:2. doi: 10.3389/fcell.2015.00002. PMID: 25699255; PMCID: PMC4313779.
- Taylor AM, Blurton-Jones M, Rhee SW, Cribbs DH, Cotman CW, Jeon NL. A microfluidic culture platform for CNS axonal injury, regeneration and transport. Nat Methods. 2005 Aug;2(8):599-605. doi: 10.1038/nmeth777. PMID: 16094385; PMCID: PMC1558906.
- Zhao Y, Demirci U, Chen Y, Chen P. Multiscale brain research on a microfluidic chip. Lab Chip. 2020 May 7;20(9):1531-1543. doi: 10.1039/c9lc01010f. Epub 2020 Mar 9. PMID: 32150176.
- https://www.nationalgeographic.com/science/health-and-human-body/human-body/brain/