Review written by the Editor

Metrion Biosciences and AstraZeneca joined forces on Tuesday 8^th May 2018 to co-host the fifth Cambridge Ion Channel Forum at Medimmune’s Milstein Building on Granta Park, Cambridge (UK). Established in 2011, with previous co-organisers including Neusentis, Medimmune and BioFocus, this afternoon session of ion channel focused presentations provides an opportunity for delegates to participate in networking, present a poster and listen to presentations from respected ion channel researchers. A recurring theme throughout the 2018 event was the importance of automated patch clamp (APC) electrophysiology in support of the optimisation of small molecules, biologics and in the early cardiac safety profiling of selected compound series.

Professor Peter McNaughton gave the keynote speech

King’s College London’s Professor Peter McNaughton, who was also a presenter at the 2011 meeting, gave the 2018 the Keynote Lecture summarising his team’s progress towards developing selective hyperpolarization-activated cyclic nucleotide-gated ion channel blockers as novel analgesics for neuropathic pain. This research being founded on the observation that specific deletion of HCN2 in nociceptive neurons leads to reduced neuropathic and inflammatory pain sensation, without effects on normal sensation of acute pain.

Peter outlined the evolution of his project to develop potent and selective HCN2 blockers for therapeutic use in the clinic, with a key project objective of minimising block of HCN4 channels in the heart. Peter also touched upon his research into tinnitus, via a collaboration with Mark Wallace and Deborah Hall from the University of Nottingham. The hypothesis behind this work being that tinnitus may be reduced by use of HCN2 blockers to reduce the abnormally high firing in unmyelinated auditory nerve fibres. Both of Peter’s research programmes has significant therapeutic value and we look forward to developments towards the clinic.

Assessing the hERG liability of small molecules

Matt Bridgland-Taylor then presented a case study combining electrophysiology with intracellular concentration analysis to assess the hERG liability of small molecules. In addition to assessing any link between the intracellular concentration and the kinetic profile of block, this also allowed to verify that the hERG inactive compounds were accessing the CHO cells used in the electrophysiology assay.

Iontas’ KnotBody™ technology

Moving away from the focus on small molecules, Damian Bell gave an overview of Iontas’ KnotBody™ technology, whereby knottin toxins (cysteine knot mini-proteins) are fused into peripheral complementarity-determining regions (CDRs) of the antibody VL domain. This approach offers the potential for retaining the ion channel blocking activity of the knottin, whilst gaining an extended half-life and additional specificity conferred by multiple contact surfaces of the antibody. Damian presented proof of concept data where phage display was used to engineer specificity into both antibody and peptide, with QPatch electrophysiology data presented for both K_v1.3 and ASIC1a.

Skeletal muscle channelopathies

Skeletal muscle channelopathies was the topic of choice for Roope Mannikko from University College London, who discussed myotonia and periodic paralysis and the effect of Na_v1.4 channelopathies in relation to infant sudden death syndrome. Roope’s group has also demonstrated the use of NMR techniques to probe the interactions of Voltage-Sensing Domain (VSD)-1 with HM-3, a crab spider toxin which is known to inhibit gating pore currents due to mutations found in patients with Hypokalemic Periodic Paralysis (HypoPP).

£200,000 funding to further optimise the preclinical properties of lead series compounds

The afternoon was concluded by Metrion Biosciences’ CSO Marc Rogers presenting an overview of Metrion’s use of QPatch APC assays to support identification of novel small molecule inhibitors of the K_v1.3 channel to treat auto-immune disorders. The programme has identified nM potency blockers with good gene family but no species selectivity issues, strong efficacy in native human T-cell assays, and superior drug-like properties compared to leading preclinical small molecules and biologics such as ShK-186 (Dalazatide, Kineta Therapeutics).

Metrion has secured £200,000 Innovate UK funding to further optimise the preclinical properties of lead series compounds, and plans to secure a collaboration partner to further develop immune-sparing K_v1.3 drug candidates for the treatment of autoimmune and neurodegenerative diseases in the near future.

Future events

The next Metrion Biosciences hosted event will be on 11^th July 2018. Professor Trevor Jones will be presenting “Disruptive Influences on Drug Discovery and Healthcare Delivery”.

Review by the Editor

Researchers gather for interactive forum

Metrion Biosciences and Axol Bioscience joined forces on Wednesday 23^rd May to co-host the 2018 “Interactive Stem Cell Forum” in Cambridge (UK). A meeting featuring a morning of informative and thought-provoking talks from leading academic and industry-based researchers working in the stem cell field, followed by an afternoon of laboratory demonstrations in Metrion’s Granta Park headquarters.

The meeting enabled researchers from across Cambridge and the surrounding area to attend an event focused solely upon recent developments in the field of stem cell research spanning neuroscience and cardiac topics. It was also an opportunity for attendees to network with each other and also see demonstrations utilising Axol’s Induced Pluripotent Stem Cells (iPSCs) in Metrion’s laboratories; where the Metrion team also showcased manual patch electrophysiology, QPatch 48 automated electrophysiology and microelectrode array (MEA) assay platforms.

Review of available techniques applied to iPSC research

The morning session, chaired by Metrion Biosciences’ CSO Marc Rogers, started with a presentation by Matthew Daniels, a Consultant Cardiologist based at the University of Oxford. Matthew described some limitations of technologies that have previously been applied to iPSC research. For example chemical dyes such as BAPTA-AM and Fura-2 have significant cellular toxicity,  evidenced by such dyes negatively effecting the contractility properties of iPSC-derived cardiomyocytes. 

Matthew is a strong advocate for the adoption of alternative fluorescent/luminescent tools and optogenetic-based stimulation for iPSC cardiomyocyte research, he provided a thorough review of the available techniques and described some of his research into non-invasive phenotyping and drug screening. Use of such technology has enabled the monitoring of cells for periods of up to 90 days in his laboratory. He also presented preliminary results using microarrays of single cells on a single assay plate that may have potential for scale up and use in drug discovery.

The objectives of the CiPA initiative

The co-hosting companies also gave data-led presentations, with Metrion’s Sarah Williams discussing the establishment of Axol’s cardiomyocytes as a model system using manual patch clamp electrophysiology in Metrion Biosciences laboratories. Sarah reviewed the objectives of the Comprehensive in vitro Proarrhythmia Assay (CiPA) initiative, a multi-agency strategic enterprise with the objective of improving cardiac safety screening of potential new drugs.

Whilst Metrion has a substantial validation dataset for three of the CiPA ‘pillars’ Sarah focused on recent work using Axol’s atrial and ventricular phenotype human iPSC derived cardiomyocytes. Sarah’s presentation can be found here and an accompanying poster, presented at the 2018 Select Biosciences Stem Cells In Drug Discovery meeting, is here. Thanks to all Axol and Metrion staff who contributed towards this work

The pathology of Amyotrophic Lateral Sclerosis (ALS)

The pathology of Amyotrophic Lateral Sclerosis (ALS) was the topic of choice for Gareth Miles from the University of St Andrews, who discussed the use of stem cell-based technology to investigate the interactions between astrocytes and motor neurons in a humanised ALS model. Historic suffers of this disease include American baseball player Lou Gehrig and the renowned physicist Professor Stephen Hawking.

Using iPSC derived co-culture of astrocytes derived from healthy individuals and ALS patients with the TARDPB or C9ORF72 mutations with motor neurones from healthy individuals, the Miles’ group has demonstrated hypo excitability in the ALS astrocyte co-culture motor neurones correlating with loss of sodium and potassium currents. This data, combined with CRISPR studies removing the C9ORF72 ALS-causing mutation, implicates astrocyte-neuron signalling as a promising target for ALS drug discovery.

The phenotypic and functional characterisation of human iPSC derived microglia

Zoe Nilsson from Axol Bioscience then discussed the phenotypic and functional characterisation of human iPSC derived microglia. These are innate immune cells found within the central nervous system which possess key roles in neurogenesis and immunity and which Axol have developed as a co-culture with human iPSC derived cortical neurons. Zoe presented the use of such tools in drug discovery and linked back to Gareth’s earlier talk by describing the dangers of the overactivation of microglia which can lead to neuroinflammation and can play a critical role in ALS and other neurodegenerative disorders.

Using tissue engineering techniques to model Alzheimer’s Disease

Zoe was followed by Eric Hill from Aston University, who described his work using tissue engineering techniques to model Alzheimer’s Disease. Eric spoke about the many difficulties associated with drug discovery in the Alzheimer’s field, attributing this largely to the lack of high quality predictive experimental models. Additionally, it is now widely accepted that the first stages of Alzheimer’s disease may occur around twenty to thirty years before initiation of memory loss – further complicating the situation for disease modelling.

In a quest to produce a high quality predictive in vitro model the Hill lab is pioneering an approach using Alzheimer’s Disease-derived iPSC and 3D culture techniques. As part of the MESO-BRAIN initiative Eric’s team have been 3D printing cultures of Alzheimer’s and healthy’ iPSC astrocytes to form neural networks with defined biological architecture in polymer scaffolds.  Conductive polymer scaffolds may be used, enabling monitoring of electrical activity within the organoid structure or, alternatively, real time imaging techniques can be applied. Ultimately the Hill lab aims to produce a model suitable for early discovery compound screening or to trial other novel treatments for Alzheimer’s Disease.

The use of iPSCs in both disease modelling and as a safety pharmacology platform

The final Speaker was Daniel Sinnecker, a cardiologist from the Technical University of Munich. Daniel discussed the use of iPSCs in both disease modelling and as a safety pharmacology platform. For example, use of iPSC as an integral component in CiPA which linked well to earlier content within Sarah Williams’ presentation. Daniel also discussed the use of lentiviral transduction to insert genetically encoded voltage sensors into iPSC cardiomyocytes from healthy and long-QT type 1 (LQT1) patents.  Using this technique the Sinnecker lab has been able to quantify cardiomyocyte action potential characteristics in healthy iPSC and also demonstrate early after depolarisations in the LQT1 mutants. This technique shows great promise for evaluating cardiomyocyte iPSC characteristics over an extended time period.

Laboratory demonstrations

After a networking lunch, which prompted further conversation around the various themes presented in the morning session, Metrion Biosciences hosted a series of laboratory demonstrations in our Granta Park facility. The demonstrations involved use of Axol’s iPSCs, with Sarah Williams showcasing Metrion’s “gold standard” conventional manual patch clamp electrophysiology capabilities.

Edd Humphries then demonstrated one of Metrion’s QPatch 48 automated electrophysiology platforms using clonal stable cell lines. The QPatch is a device that produces high quality electrophysiology data for both routine screening in support of medicinal chemistry activities and is the platform upon which Metrion has validated its suite of high quality CiPA-compliant safety profiling assays.

Finally, Said El Haou showcased Metrion’s Axion Biosystem’s Maestro MEA system, a versatile platform able to capture real-time, information rich, recordings from iPSC and cultured native neurons, with the facility to evaluate effects of novel compounds over extended time periods (days to weeks).

Acknowledgements

This event, closely followed the 2018 Cambridge Ion Channel Forum co-hosted by Metrion Biosciences and AstraZeneca on 8^th May, was a further example of Metrion Biosciences commitment to promoting and generating high quality science in the Cambridge bio cluster. We would like to thank the Axol team for being excellent co-hosts and we look forward to organising our next event. You can sign up for updates regarding Metrion sponsored events, Metrion’s external speaker presentations and services updates HERE and you can refine your topics of interest and opt out at any time.