Tag Archives: animal testing

Predicting drug side effects with guts-on-a-chip

It’s been a while since I’ve featured a story about a technology that could drastically reduce (or even eliminate) animal testing. Researchers in the Netherlands have announced some guts-on-a-chip research that may do just that. From an Aug. 22, 2017 news item on ScienceDaily,

Research conducted at Leiden has established that guts-on-chips respond in the same way to aspirin as real human organs do. This is a sign that these model organs are good predictors of the effect of medical drugs on the human body.

A method to test medical drugs for efficacy and potential side-effects, but then much cheaper and using the fewest possible lab animals: this is likely to be possible in future thanks to organs-on-chips, miniature model organs on microchips. In these model organs, which are equipped with human organ cells and microfluidic channels, researchers and pharmacists can mimic the working of an organ.

An Aug. 17, 2017 University of Leiden (Universiteit Leiden) press release, which originated the news item, provides more detail,

Leiden researchers, their spin-off company Mimetas and pharmaceutical company Roche have now shown that one type of organ chip experiences the same side-effects from the drug aspirin as the same organ in the human body. This is good news, because it is a sign that these miniature model organs are good predictors of the effect of medical drugs in the human body.

Aspirin

The researchers exposed 357 guts-on-chips for a significant period to the substance acetylsalicylic acid, better known as the analgesic aspirin. It has been known for a long time already that this substance can lead to gastrointestinal perforation, a complication that can be fatal if untreated. ‘We saw exactly the same side-effects occur in our guts-on-chips,’ says Professor of Analytical Biosciences Thomas Hankemeier. ‘In our model guts the gut wall also became more permeable after the drug had been administered.’

Effectiveness of candidate drugs

According to Hankemeier, the research shows that organs-on-chips are suited to testing a medical drug for efficacy and side-effects. This is good news for pharmacists, because the model organs make it easier for them to evaluate whether candidate drugs are effective or harmful. Many substances would be excluded from futher research before a drug entered the lab animal phase. This would help reduce the cost of drug production and mean less animal testing.

Diagnosing diseases

Organs-on-chips have taken off in recent years. They will be increasingly important in the near future, not just in drug development but also in the diagnosis of disease. Leiden researchers are at the forefront of this development. Hankemeier and a number of other groups (Erasmus MC, VUmc, RU Groningen) have been awared a 1.5 million ZonMW grant to research the effect of the body’s micro-organisms in the gut on the development of dementia. Organ-on-a-chip technology will play an important role here. Mimetas is the first company in the world to produce and sell organ chips on a large scale.

Here’s a link to and a citation for the paper,

Membrane-free culture and real-time barrier integrity assessment of perfused intestinal epithelium tubes by Sebastiaan J. Trietsch, Elena Naumovska, Dorota Kurek, Meily C. Setyawati, Marianne K. Vormann, Karlijn J. Wilschut, Henriëtte L. Lanz, Arnaud Nicolas, Chee Ping Ng, Jos Joore, Stefan Kustermann, Adrian Roth, Thomas Hankemeier, Annie Moisan, & Paul Vulto. Nature Communications 8, Article number: 262 (2017) doi:10.1038/s41467-017-00259-3 Published online: 15 August 2017

This paper is open access.

You can find Mimetas here.

Replicating brain’s neural networks with 3D nanoprinting

An announcement about European Union funding for a project to reproduce neural networks by 3D nanoprinting can be found in a June 10, 2016 news item on Nanowerk,

The MESO-BRAIN consortium has received a prestigious award of €3.3million in funding from the European Commission as part of its Future and Emerging Technology (FET) scheme. The project aims to develop three-dimensional (3D) human neural networks with specific biological architecture, and the inherent ability to interrogate the network’s brain-like activity both electrophysiologically and optically. It is expected that the MESO-BRAIN will facilitate a better understanding of human disease progression, neuronal growth and enable the development of large-scale human cell-based assays to test the modulatory effects of pharmacological and toxicological compounds on neural network activity. The use of more physiologically relevant human models will increase drug screening efficiency and reduce the need for animal testing.

A June 9, 2016 Institute of Photonic Sciences (ICFO) press release (also on EurekAlert), which originated the news item, provides more detail,

About the MESO-BRAIN project

The MESO-BRAIN project’s cornerstone will use human induced pluripotent stem cells (iPSCs) that have been differentiated into neurons upon a defined and reproducible 3D scaffold to support the development of human neural networks that emulate brain activity. The structure will be based on a brain cortical module and will be unique in that it will be designed and produced using nanoscale 3D-laser-printed structures incorporating nano-electrodes to enable downstream electrophysiological analysis of neural network function. Optical analysis will be conducted using cutting-edge light sheet-based, fast volumetric imaging technology to enable cellular resolution throughout the 3D network. The MESO-BRAIN project will allow for a comprehensive and detailed investigation of neural network development in health and disease.

Prof Edik Rafailov, Head of the MESO-BRAIN project (Aston University) said: “What we’re proposing to achieve with this project has, until recently, been the stuff of science fiction. Being able to extract and replicate neural networks from the brain through 3D nanoprinting promises to change this. The MESO-BRAIN project has the potential to revolutionise the way we are able to understand the onset and development of disease and discover treatments for those with dementia or brain injuries. We cannot wait to get started!”

The MESO-BRAIN project will launch in September 2016 and research will be conducted over three years.

About the MESO-BRAIN consortium

Each of the consortium partners have been chosen for the highly specific skills & knowledge that they bring to this project. These include technologies and expertise in stem cells, photonics, physics, 3D nanoprinting, electrophysiology, molecular biology, imaging and commercialisation.

Aston University (UK) Aston Institute of Photonic Technologies (School of Engineering and Applied Science) is one of the largest photonic groups in UK and an internationally recognised research centre in the fields of lasers, fibre-optics, high-speed optical communications, nonlinear and biomedical photonics. The Cell & Tissue Biomedical Research Group (Aston Research Centre for Healthy Ageing) combines collective expertise in genetic manipulation, tissue engineering and neuronal modelling with the electrophysiological and optical analysis of human iPSC-derived neural networks. Axol Bioscience Ltd. (UK) was founded to fulfil the unmet demand for high quality, clinically relevant human iPSC-derived cells for use in biomedical research and drug discovery. The Laser Zentrum Hannover (Germany) is a leading research organisation in the fields of laser development, material processing, laser medicine, and laser-based nanotechnologies. The Neurophysics Group (Physics Department) at University of Barcelona (Spain) are experts in combing experiments with theoretical and computational modelling to infer functional connectivity in neuronal circuits. The Institute of Photonic Sciences (ICFO) (Spain) is a world-leading research centre in photonics with expertise in several microscopy techniques including light sheet imaging. KITE Innovation (UK) helps to bridge the gap between the academic and business sectors in supporting collaboration, enterprise, and knowledge-based business development.

For anyone curious about the FET funding scheme, there’s this from the press release,

Horizon 2020 aims to ensure Europe produces world-class science by removing barriers to innovation through funding programmes such as the FET. The FET (Open) funds forward-looking collaborations between advanced multidisciplinary science and cutting-edge engineering for radically new future technologies. The published success rate is below 1.4%, making it amongst the toughest in the Horizon 2020 suite of funding schemes. The MESO-BRAIN proposal scored a perfect 5/5.

You can find out more about the MESO-BRAIN project on its ICFO webpage.

They don’t say anything about it but I can’t help wondering if the scientists aren’t also considering the possibility of creating an artificial brain.

Canadian researchers develop test for exposure to nanoparticles*

The Canadian Broadcasting Corporation’s online news features a May 21, 2014 article by Emily Chung regarding research from the University of Toronto that may enable a simple skin test for determining nanoparticle exposure,

Canadian researchers have developed the first test for exposure to nanoparticles — new chemical technology found in a huge range of consumer products — that could potentially be used on humans.

Warren Chan, a University of Toronto [U of T] chemistry professor, and his team developed the skin test after noticing that some mice changed colour and others became fluorescent (that is, they glowed when light of certain colours were shone on them) after being exposed to increasing levels of different kinds of nanoparticles. The mice were being used in research to develop cancer treatments involving nanoparticles.

There is some evidence that certain types and levels of exposure may be harmful to human health. But until now, it has been hard to link exposure to health effects, partly due to the challenge of measuring exposure.

“There’s no way to determine how much [sic] nanoparticles you’ve been exposed to,” said Chan in an interview with CBCNews.ca.

There was one way to measure nanoparticle exposure in mice —  but it required the animals to be dead. At that point, they would be cut open and tests could be run on organs such as the liver and spleen where nanoparticles accumulate.

A May 14, 2014 article by Nancy Owano on phys.org provides more details (Note: Links have been removed),

They [researchers] found that different nanoparticles are visible through the skin under ambient or UV light. They found that after intravenous injection of fluorescent nanoparticles, they accumulate and can be observed through the skin. They also found that the concentration of these nanoparticles can be directly correlated to the injected dose and their accumulations in other organs.

In their discussion over selecting nanoparticles used in mouse skin, they said, “Gold nanoparticles are commonly used in molecular diagnostics and drug delivery applications. These nanomaterials were selected for our initial studies as they are easily synthesized, have a distinct ruby color and can be quantified by inductively coupled plasma atomic emission spectroscopy (ICP-AES).”

Work involved in the study included designing and performing experiments, pathological analysis, and data analysis. Their discovery could be used to better predict how nanoparticles behave in the body.

Here’s a link to and a citation for the paper,

Nanoparticle exposure in animals can be visualized in the skin and analysed via skin biopsy by Edward A. Sykes, Qin Dai, Kim M. Tsoi, David M. Hwang & Warren C. W. Chan. Nature Communications 5, Article number: 3796 doi:10.1038/ncomms4796 Published 13 May 2014

This paper is behind a paywall.

* Posting’s head changed from ‘Canadians and exposure to nanoparticles; to the more descriptive ‘Canadian researchers develop test for exposure to nanoparticles’., May 27, 2014.

Graphene-based sensor mimics pain (mu-opioid) receptor

I once had a job where I had to perform literature searches and read papers on pain research as it related to morphine tolerance. Not a pleasant task, it has left me eager to encourage and write about alternatives to animal testing, a key component of pain research. So, with a ‘song in my heart’, I feature this research from the University of Pennsylvania written up in a May 12, 2014 news item on ScienceDaily,

Almost every biological process involves sensing the presence of a certain chemical. Finely tuned over millions of years of evolution, the body’s different receptors are shaped to accept certain target chemicals. When they bind, the receptors tell their host cells to produce nerve impulses, regulate metabolism, defend the body against invaders or myriad other actions depending on the cell, receptor and chemical type.

Now, researchers from the University of Pennsylvania have led an effort to create an artificial chemical sensor based on one of the human body’s most important receptors, one that is critical in the action of painkillers and anesthetics. In these devices, the receptors’ activation produces an electrical response rather than a biochemical one, allowing that response to be read out by a computer.

By attaching a modified version of this mu-opioid receptor to strips of graphene, they have shown a way to mass produce devices that could be useful in drug development and a variety of diagnostic tests. And because the mu-opioid receptor belongs to the most common class of such chemical sensors, the findings suggest that the same technique could be applied to detect a wide range of biologically relevant chemicals.

A May 6, 2014 University of Pennsylvania news release, which originated the news item, describes the main teams involved in this research along with why and how they worked together (Note: Links have been removed),

The study, published in the journal Nano Letters, was led by A.T. Charlie Johnson, director of Penn’s Nano/Bio Interface Center and professor of physics in Penn’s School of Arts & Sciences; Renyu Liu, assistant professor of anesthesiology in Penn’s Perelman School of Medicine; and Mitchell Lerner, then a graduate student in Johnson’s lab. It was made possible through a collaboration with Jeffery Saven, professor of chemistry in Penn Arts & Sciences. The Penn team also worked with researchers from the Seoul National University in South Korea.

Their study combines recent advances from several disciplines.

Johnson’s group has extensive experience attaching biological components to nanomaterials for use in chemical detectors. Previous studies have involved wrapping carbon nanotubes with single-stranded DNA to detect odors related to cancer and attaching antibodies to nanotubes to detect the presence of the bacteria associated with Lyme disease.

After Saven and Liu addressed these problems with the redesigned receptor, they saw that it might be useful to Johnson, who had previously published a study on attaching a similar receptor protein to carbon nanotubes. In that case, the protein was difficult to grow genetically, and Johnson and his colleagues also needed to include additional biological structures from the receptors’ natural membranes in order to keep them stable.

In contrast, the computationally redesigned protein could be readily grown and attached directly to graphene, opening up the possibility of mass producing biosensor devices that utilize these receptors.

“Due to the challenges associated with isolating these receptors from their membrane environment without losing functionality,” Liu said, “the traditional methods of studying them involved indirectly investigating the interactions between opioid and the receptor via radioactive or fluorescent labeled ligands, for example. This multi-disciplinary effort overcame those difficulties, enabling us to investigate these interactions directly in a cell free system without the need to label any ligands.”

With Saven and Liu providing a version of the receptor that could stably bind to sheets of graphene, Johnson’s team refined their process of manufacturing those sheets and connecting them to the circuitry necessary to make functional devices.

The news release provides more technical details about the graphene sensor,

“We start by growing a piece of graphene that is about six inches wide by 12 inches long,” Johnson said. “That’s a pretty big piece of graphene, but we don’t work with the whole thing at once. Mitchell Lerner, the lead author of the study, came up with a very clever idea to cut down on chemical contamination. We start with a piece that is about an inch square, then separate them into ribbons that are about 50 microns across.

“The nice thing about these ribbons is that we can put them right on top of the rest of the circuitry, and then go on to attach the receptors. This really reduces the potential for contamination, which is important because contamination greatly degrades the electrical properties we measure.”

Because the mechanism by which the device reports on the presence of the target molecule relies only on the receptor’s proximity to the nanostructure when it binds to the target, Johnson’s team could employ the same chemical technique for attaching the antibodies and other receptors used in earlier studies.

Once attached to the ribbons, the opioid receptors would produce changes in the surrounding graphene’s electrical properties whenever they bound to their target. Those changes would then produce electrical signals that would be transmitted to a computer via neighboring electrodes.

The high reliability of the manufacturing process — only one of the 193 devices on the chip failed — enables applications in both clinical diagnostics and further research. [emphasis mine]

“We can measure each device individually and average the results, which greatly reduces the noise,” said Johnson. “Or you could imagine attaching 10 different kinds of receptors to 20 devices each, all on the same chip, if you wanted to test for multiple chemicals at once.”

In the researchers’ experiment, they tested their devices’ ability to detect the concentration of a single type of molecule. They used naltrexone, a drug used in alcohol and opioid addiction treatment, because it binds to and blocks the natural opioid receptors that produce the narcotic effects patients seek.

“It’s not clear whether the receptors on the devices are as selective as they are in the biological context,” Saven said, “as the ones on your cells can tell the difference between an agonist, like morphine, and an antagonist, like naltrexone, which binds to the receptor but does nothing. By working with the receptor-functionalized graphene devices, however, not only can we make better diagnostic tools, but we can also potentially get a better understanding of how the bimolecular system actually works in the body.”

“Many novel opioids have been developed over the centuries,” Liu said. “However, none of them has achieved potent analgesic effects without notorious side effects, including devastating addiction and respiratory depression. This novel tool could potentially aid the development of new opioids that minimize these side effects.”

Wherever these devices find applications, they are a testament to the potential usefulness of the Nobel-prize winning material they are based on.

“Graphene gives us an advantage,” Johnson said, “in that its uniformity allows us to make 192 devices on a one-inch chip, all at the same time. There are still a number of things we need to work out, but this is definitely a pathway to making these devices in large quantities.”

There is no mention of animal research but it seems likely to me that this work could lead to a decreased use of animals in pain research.

This project must have been quite something as it involved collaboration across many institutions (from the news release),

Also contributing to the study were Gang Hee Han, Sung Ju Hong and Alexander Crook of Penn Arts & Sciences’ Department of Physics and Astronomy; Felipe Matsunaga and Jin Xi of the Department of Anesthesiology at the Perelman School of Medicine, José Manuel Pérez-Aguilar of Penn Arts & Sciences’ Department of Chemistry; and Yung Woo Park of Seoul National University. Mitchell Lerner is now at SPAWAR Systems Center Pacific, Felipe Matsunaga at Albert Einstein College of Medicine, José Manuel Pérez-Aguilar at Cornell University and Sung Ju Hong at Seoul National University.

Here’s a link to and a citation for the paper,

Scalable Production of Highly Sensitive Nanosensors Based on Graphene Functionalized with a Designed G Protein-Coupled Receptor by Mitchell B. Lerner, Felipe Matsunaga, Gang Hee Han, Sung Ju Hong, Jin Xi, Alexander Crook, Jose Manuel Perez-Aguilar, Yung Woo Park, Jeffery G. Saven, Renyu Liu, and A. T. Charlie Johnson.Nano Lett., Article ASAP
DOI: 10.1021/nl5006349 Publication Date (Web): April 17, 2014
Copyright © 2014 American Chemical Society

This paper is behind a paywall.

Nanomaterials, toxicology, and alternatives to animal testing

It seems that alternatives to animal testing may offer some additional capabilities for nanotoxicology studies according to an Aug. 21, 2013 news item on Nanowerk,

A group of international experts from government, industry and academia have concluded that alternative testing strategies (ATSs) that don’t rely on animals will be needed to cope with the wave of new nanomaterials emerging from the boom in nanoscience and nanotechnology. …

… Tests on laboratory mice, rats and other animals have been the standard way of checking new materials for health and environmental effects. Since those tests are costly, labor-intensive and time-consuming, workshop participants considered whether ATSs could have a larger role in checking the safety of ENMs [engineered nanomaterials].

They concluded that rapid cellular screening, computer modeling and other ATSs could serve as quick, cost-effective and reliable approaches for gathering certain types of information about the health and environmental effects of ENMs. “After lively discussions, a short list of generally shared viewpoints on this topic was generated, including a general view that ATS approaches for ENMs can significantly benefit chemical safety analysis,” they say.

The experts have had their consensus statement from the workshop published and before offering a citation for and a link to the statement, here’s the Abstract,

There has been a conceptual shift in toxicological studies from describing what happens to explaining how the adverse outcome occurs, thereby enabling a deeper and improved understanding of how biomolecular and mechanistic profiling can inform hazard identification and improve risk assessment. Compared to traditional toxicology methods, which have a heavy reliance on animals, new approaches to generate toxicological data are becoming available for the safety assessment of chemicals, including high-throughput and high-content screening (HTS, HCS). With the emergence of nanotechnology, the exponential increase in the total number of engineered nanomaterials (ENMs) in research, development, and commercialization requires a robust scientific approach to screen ENM safety in humans and the environment rapidly and efficiently. Spurred by the developments in chemical testing, a promising new toxicological paradigm for ENMs is to use alternative test strategies (ATS), which reduce reliance on animal testing through the use of in vitro and in silico methods such as HTS, HCS, and computational modeling. Furthermore, this allows for the comparative analysis of large numbers of ENMs simultaneously and for hazard assessment at various stages of the product development process and overall life cycle. [emphasis mine] Using carbon nanotubes as a case study, a workshop bringing together national and international leaders from government, industry, and academia was convened at the University of California, Los Angeles, to discuss the utility of ATS for decision-making analyses of ENMs. …

It seems that ATS has opened the door to more comprehensive testing (as per life cycles) than has previously been possible.

For the curious, here’s the citation for and the link to the published paper,

A Multi-Stakeholder Perspective on the Use of Alternative Test Strategies for Nanomaterial Safety Assessment by Andre E. Nel, Elina Nasser, Hilary Godwin, David Avery, Tina Bahadori, Lynn Bergeson #, Elizabeth Beryt, James C. Bonner, Darrell Boverhof, Janet Carter, Vince Castranova, J. R. DeShazo, Saber M. Hussain ●, Agnes B. Kane, Frederick Klaessig, Eileen Kuempel, Mark Lafranconi, Robert Landsiedel, Timothy Malloy, Mary Beth Miller, Jeffery Morris, Kenneth Moss, Gunter Oberdorster, Kent Pinkerton, Richard C. Pleus, Jo Anne Shatkin, Russell Thomas, Thabet Tolaymat, Amy Wang, and Jeffrey Wong. ACS Nano, Article ASAP DOI: 10.1021/nn4037927 Publication Date (Web): August 7, 2013

Copyright © 2013 American Chemical Society

This article is behind a paywall.

Animal love and nanotechnology

The researchers at the Fraunhofer Institute for Modular State Technologies (EMFT) have announced a nanosensor technique they’re developing to minimize the use of animals in scientific experiments. From the Jan. 10, 2012 news item on the American Association for the Advancement of Science’s (AAAS) EurekAlert,

Countless mice, rats and rabbits die every year in the name of science – and the situation is getting worse. While German laboratories used some 2.41 million animals for scientific research in 2005, by 2009 this number had grown to 2.79 million. One third were destined for fundamental biology research, and the majority were used for researching diseases and developing medical compounds and devices. People demand medicines that are safe and therapies that are tolerable, but hardly anyone is happy to accept the need for animal testing. [emphasis mine]

Yes, having read studies where they used animals for pain research (I was doing some literature searches and reading for a psychiatrist whose specialty is pain reduction [and, if possible, elimination]), I heartily concur with that last comment. Thank you to all the scientists who are working to eliminate that practice.

Since I’m not sure how long a news item remains posted on EurekAlert, I tracked down the Fraunhofer’s Research News(letter) dated 01.2012 (EMFT) for a description of what they are doing and how they are using nanosensors,

“We’re basically using a test tube to study the effects of chemicals and their potential risks. What we do is take living cells, which were isolated from human and animal tissue and grown in cell cultures, and expose them to the substance under investigation,” explains Dr. Jennifer Schmidt of the EMFT. If a given concentration of the substance is poisonous to the cell, it will die. This change in “well-being” can be rendered visible by the sensor nanoparticles developed by Dr. Schmidt and her team. (p. 5)

Specifically, here’s what they’re tracking and how they’re doing it,

Cells – the tiniest living things – that are healthy store energy in the form of adenosine triphosphate (ATP). High levels of ATP are indicative of high levels of metabolic activity in cells. If a cell is severely damaged, it becomes less active, storing less energy and consequently producing less ATP. “Our nanosensors allow us to detect adenosine triphosphate and determine the state of health of cells. This makes it possible to assess the cell-damaging effects of medical compounds or chemicals,” says Schmidt.

In order for the nanoparticles to register the ATP, researchers give them two fl uorescent dyes: a green indicator dye that is sensitive to ATP, and a red reference dye that does not change color. Next, the scientists introduce the particles to living cells and observe them under a fluorescence microscope. The degree to which the particles light up depends on the quantity of ATP present. The more yellow is visible in the overlay image, [emphasis mine] the more active are the cells. If their health were impaired, the overlay image would appear much redder. “We could in future use cancer cells to test the effectiveness of newly developed chemotherapy agents. If the nanosensors detect a low concentration of ATP in the cells, we’ll know that the new treatment is either inhibiting tumor cell growth or even killing them,” says Schmidt. “The most promising agents could then be studied further.” (p. 5)

This is the “overlay image” mentioned,

The yellow nanosensor signal in the overlay image (right) shows that the cells are active. If they were unhealthy, they would appear much redder. Center: the indicator dye signal. Left: the reference dye signal. Credit: Fraunhofer EMFT

I trust we’ll be hearing more about this research.

Global TV (national edition) and nanotechnology; EPA develops a ‘kinder to animals’ nanomaterials research strategy

Wouldn’t you know it? Just as soon as I finish my ‘science communication in Canada’ series, Global TV’s national news starts broadcasting a series on nanotechnology. Interestingly, the focus in part 1 is on medicine only. There was no mention of any other kind of application or the fact that we already have many nanotechnology-based products available in consumer markets. Maybe they’ll mention these other sectors in subsequent parts of the series.

They too (it was one of the problems I mentioned at my recent conference talk at ISEA 2009) were stuck for ways of communicating nanotechnology and so reverted to the human hair example (i.e. a nanometer = 1/100,000 of a human hair). I f you want to see part 1 of the series, it’s here.  Oh, they have beautiful graphics.

The US Environmental Protection Agency (EPA) recently announced a nanomaterials research strategy which I mentioned here in my Oct. 1, 2009 posting and they’ve already revised it. This time it’s all about the animals. According to the news item on Azonano,

Importantly, the research strategy articulates the goal of identifying non-animal methods that may ultimately be able to preclude the perceived need for any in vivo testing. The EPA appears to have taken to heart the principles outlined in the National Academy of Sciences’ report ‘Toxicity Testing in the 21st Century: A Vision and a Strategy,’ which calls for increased use of current non-animal technologies and biological understanding that is more precise, relevant, and that will improve hazard assessment.

There’s more at Azonano. I’m glad to see that the effort to move away from animal testing is being embraced.