Central Neuronal Firing
Metrion offers a set of reliable and reproducible translational neuroscience assays to demonstrate the efficacy, selectivity, potency and neurotoxic liability of your therapeutic compounds.
Table of Contents
Introduction to Translational CNS Neuroscience Assays and Platforms
Validating compounds in translational assays is vital to progressing your drug discovery program. Metrion offers a range of translational, phenotypic neuronal assays and platforms employing native rodent and human iPSCs from the central nervous system (CNS). These assays are useful for determining the efficacy, potency and mechanism-of-action of client compounds designed to treat CNS diseases such as epilepsy, anxiety, depression and neurodegeneration , as well as determining potential CNS toxicity issues for ligands expected to penetrate into the brain.
We mainly focus on electrophysiological readouts, using manual patch (voltage and current clamp) and multi-electrode array (MEA) platforms to record changes in single cell and neuronal network activity, and determine the effects of media, cell biology modulators, signalling pathways and test compounds.
These assays often need to be specifically designed for your translational neuroscience and drug discovery needs, please contact us with your requirements using the buttons below.
Multi-electrode arrays (MEA) are a powerful tool to investigate the neuronal firing fingerprint of your cells of choice over days, weeks or even months. Neurons are cultured over a large set of electrodes and over time, a network is established with distinct characteristics. Extracellular field potentials are recorded, providing a non-invasive way of monitoring neuronal activity. Cells from different origins can be compared and / or effects of compounds on excitability, connectivity and synchrony investigated.
Applications of this technology include examining potential neurotoxicity of compounds, thereby helping to define safety margins. Alternatively, MEA recordings can be used to verify the desired actions of compounds specifically developed to be active in the central nervous system (CNS).
At Metrion, we have two different MEA systems. The Axion Maestro is a high throughput device with a total of 768 electrodes that can be utilised in 12, 48 or 96 well formats. Alternatively, we have the MED64 platform from Alpha MED, a lower throughput but highly flexible instrument with 64 electrodes that is better suited to certain applications. See our platform section for more information.
To further investigate the effects of a compound
At Metrion, we have multiple manual patch-clamp rigs available with highly trained and experienced operatives. We aim to be able to provide an integrated service where compounds can be investigated using multiple techniques (such as linking MEA work with current-clamp), and to also provide safety assays to allow assessment of the potential therapeutic window. Subsequent to current-clamp work, Metrion can also follow-up with efficacy studies against specific ion channel targets using voltage clamp recordings from native neurons or heterologous cell lines.
As nervous system side-effects continue to be one of the major causes of drug attrition, it is critical that new drug candidates are tested in predictive neurotoxicity assays.
Neurotoxicity screening can be carried out efficiently and reliably in plate-based assays such as the multi-electrode array (MEA) using peripheral and CNS neurons from native tissue or human iPSC-derived cells. Spiking activity is closely monitored over extended periods using biophysical techniques able to detect acute and chronic effects of test compounds under physiological conditions.
Multi-electrode array platforms enable
s simultaneous recording of the physiological activity from multiple neuronal cells and complex networks. Extracellular field potentials are recorded in a non-invasive manner to characterise neuronal firing before and after compound addition, detecting changes in single neuron activity as well as higher level network synchronisation. The electrophysiological behaviour of populations of disease modified neurons or cells from different sources can also be compared with relative ease.
CNS Seizure Assay
We have validated an industry-standard rat cortical CNS neuron excitability assay on a MEA platform (here) that can reliably detect inhibitory and excitatory effects of a wide range of agricultural and medical agents. Alongside the FDA’s NeuTox initiative we are also developing translational CNS seizure liability assays using human iPSC-derived CNS neurons.
Rat cortical neurons cultured on MEA plates increase their activity to become more co-ordinated and stable over time to match that of postnatal animals (Fig. 5b), after which time test compounds can be assessed for complex effects on cell firing and network bursting (Fig. 6b).
Central Neuronal Firing Resources
- Development of Native and Stem Cell-Derived Electrophysiological Assays for Neurotoxicology Screening and Translational Drug Discovery. SPS Berlin 2017 poster 142.
- Profiling endogenous sodium channels in the ND7-23 neuroblastoma cell line: implications for use as a heterologous ion channel expression system and native tissue model suitable for automated patch clamp screening. Royal Society for Chemistry Ion Channel Symposium, March 2016.
- Metrion Biosciences: high quality ion channel drug discovery service provider. Milner Therapeutics Symposium, Cambridge, 2019
Central Neuronal Firing Technologies
- Conventional manual patch clamp electrophysiology
- Plate-based microelectrode array techniques
Let’s work together
What are your specific assay needs?
If you have any questions or would like to discuss your specific assay requirements, we will put you directly in touch with a member of our scientific team.