Human beings are not the only ones who suffer from stress – even microorganisms can be affected. Now, researchers from Chalmers University of Technology, Sweden, have devised a new method to study how single biological cells react to stressful situations. Understanding these responses could help develop more effective drugs for serious diseases. As well as that, the research could even help to brew better beer. All living organisms can experience stress during challenging situations. Cells and microorganisms have complicated systems to govern how they adapt to new conditions. They can alter their own structure by incorporating or releasing many different substances into the surroundings. Due to the complexity of these molecular processes, understanding these systems is a difficult task. Chalmers researchers Daniel Midtvedt, Erik Olsén, Fredrik Höök and Gavin Jeffries have now made an important breakthrough, by looking at how individual yeast cells react to changes in the local environment – in this case an increased osmolarity, or concentration, of salt. They both identified and monitored the change of compounds within the yeast cells, one of which was a sugar, glycerol. Furthermore, they were able to measure the exact rate and amount of glycerol produced by different cells under various stress conditions. Their results have now been published in the renowned scientific journal Nature Communications. With the help of holographic microscopy, researchers have studied biological microorganisms in three dimensions to be able to see how they react to changes in their surroundings. The cells’ reactions to stress is measured through a method in which a laser beam is first split into two light paths. One of the light paths passes through a cell sample, and one does not. The two beams are then recombined at a slight offset angle. It is then possible to read changes in the cell’s properties through the variations in the beams’ phase offsets. Understanding these responses could help develop more effective drugs for serious diseases. Additionally, the research could even help to brew better beer. "Yeast and bacteria have very similar systems when it comes to response to stress, meaning the results are very interesting from a medical point of view. This could help us understand how to make life harder for undesirable bacteria which invade our body – a means to knock out their defence mechanisms,” says Daniel Midtvedt, researcher in biological physics at Chalmers, and lead writer of the scientific paper. He has been researching the subject since 2015, and, together with his colleagues, has developed a variant of holographic microscopy to study the cells in three dimensions. The method is built upon an interference imaging approach, splitting a laser beam into two light paths, with one which passes through a cell sample, and one which does not. The two beams are then recombined at a slight offset angle. This makes it possible to read changes in the cell’s properties through the variations in beam phase offsets. With this method of investigating a cell, researchers can see what different microorganisms produce under stress – without needing to use different types of traditional ‘label-based’ strategies. Their non-invasive strategy allows for multiple compounds to be detected simultaneously, without damaging the cell. The researchers now plan to use the new method in a large collaboration project, to look at the uptake of targeted biomedicines. “Hopefully, we can contribute to improved understanding of how drugs are received and processed by human cells. It is important to be able to develop new type of drugs, with the hope that we can treat those illnesses which today are untreatable,” says Chalmers professor Fredrik Höök, who further leads the research centre Formulaex, where AstraZeneca is the leading industry partner. As well as the benefit to medical researchers, improved knowledge of the impact of stress on yeast cells could be valuable for the food and drink industry – not least, when it comes to brewing better beer. “Yeast is essential for both food and drink preparation, for example in baking bread and brewing beer. This knowledge of yeast cells’ physical characteristics could be invaluable. We could optimise the products exactly as we want them,” says Daniel Midtvedt.
The new approach, reported in ACS' journal Analytical Chemistry, could be useful for medical applications in regions of the world that lack electricity and other resources. Before doctors can perform many types of blood tests, they must separate blood cells from plasma, the yellowish fluid that contains proteins, bacteria, viruses, metabolites and other substances that can be used to diagnose disease. This is most often accomplished by centrifugation, which uses high-speed rotation to sediment blood cells. However, centrifuges are expensive and require electricity that might not be available in resource-limited regions. Chien-Fu Chen, Chien-Cheng Chang and colleagues wondered if a commercially available fidget-spinner could generate enough force to separate blood plasma with the flick of a finger. To find out, the researchers placed human blood samples in tiny tubes, sealed the ends and taped a tube to each of the three prongs of a fidget-spinner. They found that by flicking the spinner with a finger three to five times, they could separate about 30 percent of the plasma with 99 percent purity in only four to seven minutes. To verify that the plasma was suitable for diagnostic tests, the researchers spiked blood with a human immunodeficiency virus-1 (HIV-1) protein, separated the plasma with the spinner and performed a paper-based detection test. The inexpensive, simple method detected clinically relevant concentrations of the viral protein in only a drop of blood.
The study's findings appeared in EBioMedicine, a publication of The Lancet. "This test solves a long-standing problem in lung transplants: detection of hidden signs of rejection," said Hannah Valantine, M.D., co-leader of the study and lead investigator of the Laboratory of Organ Transplant Genomics in the Cardiovascular Branch at NHLBI. "We're very excited about its potential to save lives, especially in the wake of a critical shortage of donor organs." The test relies on DNA sequencing, Valantine explained, and as such, represents a great example of personalized medicine, as it will allow doctors to tailor transplant treatments to those individuals who are at highest risk for rejection. Lung transplant recipients have the shortest survival rates among patients who get solid organ transplantation of any kind - only about half live past five years. Lung transplant recipients face a high incidence of chronic rejection, which occurs when the body's immune system attacks the transplanted organ. Existing tools for detecting signs of rejection, such as biopsy, either require the removal of small amounts of lung tissue or are not sensitive enough to discern the severity of the rejection. The new test appears to overcome those challenges. Called the donor-derived cell-free DNA test, the experimental test begins with obtaining a few blood droplets taken from the arm of the transplant recipient. A special set of machines then sorts the DNA fragments in the blood sample, and in combination with computer analysis, determines whether the fragments are from the recipient or the donor and how many of each type are present. Because injured or dying cells from the donor release lots of donor DNA fragments into the bloodstream compared to normal donor cells, higher amounts of donor DNA indicate a higher risk for transplant rejection in the recipient. In the study, 106 lung transplant recipients were enrolled and monitored. Blood samples collected in the first three months after transplantation underwent the testing procedure. The results showed that those with higher levels of the donor-derived DNA fragments in the first three months of transplantation were six times more likely to subsequently develop transplant organ failure or die during the study follow-up period than those with lower donor-derived DNA levels. Importantly, researchers found that more than half of the high-risk subjects showed no outward signs of clinical complications during this period.
Vaccinations against polio, diphtheria, whooping cough and tetanus have been on the list of standard infant vaccinations for decades now. Many vaccines are inactivated vaccines - that is to say, the pathogens they contain have been killed so that they can no longer harm the patient. Despite this, the vaccine provokes an immune response: The body detects a foreign intruder and begins to produce antibodies to ward off infection. To produce these vaccines, pathogens are cultivated in large quantities and then killed using toxic chemicals. The most common of these is formaldehyde - heavily diluted so it doesn’t harm the patient when the vaccination is administered. Nevertheless, there are downsides to even this minimal concentration: The toxin must remain in contact with the pathogen for days or even weeks to take effect, which has a negative impact both on the structure of the pathogen and the reproducibility of the vaccine. And in cases that call for speed – flu vaccines for instance – drug manufacturers are obliged to use higher dosages of formaldehyde. The product must then undergo a time-consuming process of filtration to avoid traces of the toxic chemical being left behind in the vaccine. Electron beams kill harmful pathogens Now, pharmaceutical companies will be able to produce inactivated vaccines without the slightest trace of toxic chemicals – quickly and reproducibly. The scientists who developed this process see its greatest potential in the production of vaccines that until now were not amenable to the method of chemical inactivation. The technique was developed jointly by researchers at the Fraunhofer Institutes for Cell Therapy and Immunology IZI, Manufacturing Engineering and Automation IPA, Organic Electronics, Electron Beam and Plasma Technology FEP and Interfacial Engineering and Biotechnology IGB. “Instead of using chemicals to inactivate the pathogens, we employ low-energy electron beams,” explains Fraunhofer IPA team leader Martin Thoma. The accelerated electrons break down the DNA of the pathogens either via direct collisions or through the generation of secondary electrons, which subsequently result in single or double strand breaks. In a nutshell, the electrons fragment the pathogens’ DNA while maintaining their external structure. This is important to trigger an effective immune response. The challenge arises from the fact that the electrons cannot penetrate very deeply into the suspension containing the pathogens - in fact, for an even dose distribution, liquid levels should not exceed 200 micrometers. Because there were no existing technologies capable of meeting these requirements, Fraunhofer IPA developed two new methods from scratch. In the first method, a cylinder is continuously wetted with the pathogen suspension, irradiated, and the inactivated liquid transferred into a sterile vessel. In other words, there are two reservoirs of liquid: one containing the active and one containing the inactive pathogens - connected to one another via a constantly turning cylindrical vessel or tumbler. “It’s a continuous process that can easily be scaled up for the mass production of vaccines,” says Thoma. The second method is more suited to lab-scale applications, in which small quantities of vaccine are produced for research or drug development purposes. In this instance, the solution containing the pathogens is placed in bags, which are then passed through the electron beam using a patented process. A collaborative undertaking This kind of project calls for a range of expertise that is perfectly covered by the four Fraunhofer Institutes involved in the initiative. Researchers at Fraunhofer IZI took responsibility for cultivating the various pathogens – including one for avian flu and one for equine influenza. “Following the irradiation, we also worked with our colleagues at Fraunhofer IGB to determine whether the pathogens had been fully inactivated, thus providing effective vaccine protection,” says Dr. Sebastian Ulbert, head of department at Fraunhofer IZI and the initiator of the project. The expertise in electron beam technology came from researchers at Fraunhofer FEP, who developed a system capable of delivering the low-energy electron beams at precise doses – this is necessary because, while the aim is to reliably inactivate the pathogen, care must also be taken to preserve the pathogen structure so that patients’ immune systems can produce the corresponding antibodies. The new technology has already been implemented, and not only on the laboratory scale: “In the fall of 2018, a research and pilot facility entered into service here at Fraunhofer IZI. Using our continuous module – the wetted tumbler – we are currently able to produce four liters of vaccine per hour,” says Ulbert. That is not far off industrial scale, given that, for certain vaccines, 15 liters of pathogen suspension can yield a million doses of vaccine. Discussions are already underway with partners in industry. However, it will be another two to four years before vaccines produced using electron beams can be tested in clinical trials.
In a paper published in PLOS ONE, scientists from the University of Surrey's Centre for Vision, Speech and Signal Processing (CVSSP) detail how, in an NHS clinical trial, they used a technique called Non-negative Matrix Factorisation to find hidden clues of possible UTI cases. The team then used novel machine learning algorithms to identify early UTI symptoms. The experiment was part of the TIHM (Technology Integrated Health Management) for dementia project, led by Surrey and Borders Partnership NHS Foundation Trust and in partnership with the University of Surrey and industry collaborators. The project, which is part of the NHS Test Beds Programme and is funded by NHS England the Office for Life Sciences, allowed clinicians to remotely monitor the health of people with dementia living at home, with the help of a network of internet enabled devices such as environmental and activity monitoring sensors, and vital body signal monitoring devices. Data streamed from these devices was analysed using machine learning solutions, and the identified health problems were flagged on a digital dashboard and followed up by a clinical monitoring team. According to The World Health Organisation, around 50 million people worldwide have dementia. This number is estimated to reach 82 million in 2030 and 152 million in 2050. According to the Alzheimer's Society, one in four hospital beds in the UK are occupied by a person with dementia, while around 22 percent of these admissions are deemed to be preventable. Payam Barnaghi, Professor of Machine Intelligence at CVSSP, said: "Urinary tract infections are one of the most common reasons why people living with dementia go into hospital. We have developed a tool that is able to identify the risk of UTIs so it is then possible to treat them early. We are confident our algorithm will be a valuable tool for healthcare professionals, allowing them to produce more effective and personalised plans for patients." Professor Adrian Hilton, Director of CVSSP, said: "This development hints at the incredible potential of Professor Barnaghi's research here at CVSSP. Machine learning could provide improved care for people living with dementia to remain at home, reducing hospitalization and helping the NHS to free up bed space." Dr Shirin Enshaeifar, Senior Research Fellow at CVSSP, said: "I am delighted to see that the algorithms we have designed have an impact on improving the healthcare of people with dementia and providing a tool for clinicians to offer better support to their patients." Professor Helen Rostill, Director of Innovation and Development at Surrey and Borders Partnership NHS Foundation Trust, said: "The TIHM for dementia study is a collaborative project that has brought together the NHS, academia and industry to transform support for people with dementia living at home and their carers. Our aim has been to create an Internet of Things led system that uses machine learning to alert our clinicians to potential health problems that we can step in and treat early. The system helps to improve the lives of people with dementia and their carers and could also reduce pressure on the NHS."
Certain bacteria and viruses can harness the cells' motility machinery to invade our bodies. Understanding how cells move – and the rod-like actin filaments that drive the process – is key to learning how to halt or promote motility to improve human health. Now, using one of the most powerful microscopes in the world, scientists from Sanford Burnham Prebys Medical Discovery Institute (SBP) and University of North Carolina at Chapel Hill (UNC-Chapel Hill) have identified a dense, dynamic and disorganized actin filament nanoscaffold – resembling a haystack – that is induced in response to a molecular signal. This is the first time researchers have directly visualized, at the molecular level, a structure that is triggered in response to a cellular signal – a key finding that expands our understanding of how cells move. The study was published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS). "Cyro-electron microscopy is revolutionizing our understanding of the inner workings of cells," says Dorit Hanein, Ph.D., senior author of the paper and professor in the Bioinformatics and Structural Biology Program at SBP. "This technology allowed us to collect robust, 3D images of regions of cells – similar to MRI, which creates detailed images of our body. We were able to visualize cells in their natural state, which revealed a never-before-seen actin nano-architecture within the cell." In the study, the scientists used SBP's cryo-electron microscope (Titan Krios), artificial intelligence (AI) and tailor-made computational and cell imaging approaches to compare nanoscale images of mouse fibroblasts to time-stamped light images of fluorescent Rac1, a protein that regulates cell movement, response to force or strain (mechanosensing) and pathogen invasion. The images revealed a densely packed, disorganized, scaffold-like structure comprised of short actin rods. These structures sprang into view in defined regions where Rac1 was activated, and quickly dissipated when Rac1 signaling stopped – in as little as two and a half minutes. This dynamic scaffold contrasted sharply with various other actin assemblies in areas of low Rac1 activation – some comprised of long, aligned rods of actin, and others comprised of short actin rods branching from the sides of longer actin filaments. The volume encasing the actin scaffold was devoid of common cellular structures, such as ribosomes, microtubules, vesicles and more, likely due to the structure's intense density. Next, the scientists would like to expand the protocol to visualize more structures that are created in response to other molecular signals and to further develop the technology to allow access to other regions of the cell. "This study is only the beginning. Now that we developed this quantitative nanoscale workflow that correlates dynamic signaling behavior with the nano-scale resolution of electron cryo-tomography, we and additional scientists can implement this powerful analytical tool not only for deciphering the inner workings of cell movement but also for elucidating the dynamics of many other macromolecular machines in an unperturbed cellular environment," says Hanein. She adds, "Actin is a building-block protein; it interacts with more than 150 actin binding proteins to generate diverse structures, each serving a unique function. We have a surplus of different signals that we would like to map, which could yield even more insights into how cells move." MEDICA-tradefair.com; Source: Sanford Burnham Prebys Medical Discovery Institute (SBP)
The device, named the WAND, works like a "pacemaker for the brain," monitoring the brain's electrical activity and delivering electrical stimulation if it detects something amiss. These devices can be extremely effective at preventing debilitating tremors or seizures in patients with a variety of neurological conditions. But the electrical signatures that precede a seizure or tremor can be extremely subtle, and the frequency and strength of electrical stimulation required to prevent them is equally touchy. It can take years of small adjustments by doctors before the devices provide optimal treatment. WAND, which stands for wireless artifact-free neuromodulation device, is both wireless and autonomous, meaning that once it learns to recognize the signs of tremor or seizure, it can adjust the stimulation parameters on its own to prevent the unwanted movements. And because it is closed-loop - meaning it can stimulate and record simultaneously - it can adjust these parameters in real-time. "The process of finding the right therapy for a patient is extremely costly and can take years. Significant reduction in both cost and duration can potentially lead to greatly improved outcomes and accessibility," said Rikky Muller, assistant professor of electrical engineering and computer sciences at Berkeley. "We want to enable the device to figure out what is the best way to stimulate for a given patient to give the best outcomes. And you can only do that by listening and recording the neural signatures." WAND can record electrical activity over 128 channels, or from 128 points in the brain, compared to eight channels in other closed-loop systems. To demonstrate the device, the team used WAND to recognize and delay specific arm movements in rhesus macaques. The device is described in a study that appeared in Nature Biomedical Engineering.
Chronic skin wounds include diabetic foot ulcers, venous ulcers and non-healing surgical wounds. Doctors have tried various approaches to help chronic wounds heal, including bandaging, dressing, exposure to oxygen and growth-factor therapy, but they often show limited effectiveness. As early as the 1960s, researchers observed that electrical stimulation could help skin wounds heal. However, the equipment for generating the electric field is often large and may require patient hospitalization. Weibo Cai, Xudong Wang and colleagues wanted to develop a flexible, self-powered bandage that could convert skin movements into a therapeutic electric field. To power their electric bandage, or e-bandage, the researchers made a wearable nanogenerator by overlapping sheets of polytetrafluoroethylene (PTFE), copper foil and polyethylene terephthalate (PET). The nanogenerator converted skin movements, which occur during normal activity or even breathing, into small electrical pulses. This current flowed to two working electrodes that were placed on either side of the skin wound to produce a weak electric field. The team tested the device by placing it over wounds on rats' backs. Wounds covered by e-bandages closed within 3 days, compared with 12 days for a control bandage with no electric field. The researchers attribute the faster wound healing to enhanced fibroblast migration, proliferation and differentiation induced by the electric field.
Cancer research at the genetic and molecular level has already enabled new targeted therapies. At the same time it has revealed the complexity and diversity of cancer - we have only seen the tip of the iceberg. Identification of new significant treatment targets in cancer cells and their supporting normal tissue requires development of a precision cancer medicine toolbox. "The iCAN flagship leverages on the unique strengths Finland has in the areas of top-level cancer research, various registers and digital health. We will for example collect gene function and drug sensitivity data from isolated tumor cells and cancer cells grown outside of the human body and combine these with digital health/lifestyle data obtained during treatment or provided by the patients themselves. Data mining is also developed by utilization of artificial intelligence. The new knowledge obtained should provide a basis for development of the right treatment for each patient," says the director of the iCAN flagship, Academy Prof. Kari Alitalo from the University of Helsinki. The iCAN flagship was awarded 11 million euros from the Academy of Finland for the first four year period. Total funding is aimed to reach an annual level of 51 million euros through commitment of the host organisations and especially through increased business collaborations. "We believe iCAN will become a global model for integration of digital health/lifestyle data with precision medicine tools. The flagship also emphasizes empowerment of the patients in all parts of the chain from research to treatment. In addition, iCAN enables new health sector innovations and business based on top research at the University of Helsinki. Over twenty pharma and digital health companies have already expressed their interest to join the flagship," notes Rector of the University of Helsinki Jari Niemela. The interdisciplinary flagship brings together researchers from cancer biology and cancer genomics to machine learning, digital health and clinical research. "Helsinki University Hospital HUS is strongly committed to taking advantage of digital health data in cancer research in the new iCAN flagship. Our data lake offers a globally unique research infrastructure for data mining and we have the first OECI-accredited Comprehensice Cancer Center in the Nordics. The flagship also supports the regional and national cancer center and the health sector growth strategy," says HUS Chief Medical Office Markku Makijarvi.
The human cytomegalovirus (CMV) is globally widespread and the majority of adults are carriers, also in Germany. After an infection, the virus hides in the body for a lifetime, which usually goes unnoticed. However, when the immune system is weakened, as is the case after transplants or when unborn children become infected during pregnancy, it can cause damage to a range of different organs including the nervous system. It is therefore important to find out whether an appropriate immune response against the virus is present in order to prevent such damage from occurring. Dr. Andreas Moosmann heads a DZIF research group at the Helmholtz Zentrum München and is specialised in studying immune responses to viruses. "In healthy humans, cytomegalovirus replication is curbed by T cells in particular," explains Moosmann. Billions of different T cells patrol through our body. Each cell has its own sensor on its surface, a so-called T cell receptor, which is able to identify just a small portion of a specific pathogen. As soon as this sensor is activated, the T cell turns into a killer cell. The infected cell is then killed and the viruses contained within it cannot replicate any longer. "Just by looking at specific T cells in the blood, we can now precisely detect whether a virus is present," says Moosmann. The problem up to now has been that complex techniques challenged such analyses. "Separate tests were required for every individual type of T cell and for each particular specificity," says Moosmann. In order to identify viruses more rapidly and precisely, Moosmann and his Munich team of scientists developed a method that enables analysis of millions of T cells with one single test. "We sequence ribonucleic acid (RNA) from the blood samples, through which we can identify existing types of T cell receptors that are specific for different parts of CMV," explains PhD candidate Alina Huth. Using this new method, the scientists were able to identify 1052 CMV-specific T cell receptors in eight healthy virus carriers. In a second group of 352 donors, the scientists measured the prevalence of these sequences, enabling them to very precisely predict infected donors. The results will be serve to establish a database of virus-specific T cell receptors. According to the scientists, this method can also be used for other viruses. Biologist Dr Xiaoling Liang is convinced that "This diagnostic method will deliver more information at a lower cost and is therefore attractive for clinicians in future. We can now develop a test that can directly determine the immune status for different viruses in one step." The applications of such a test are manifold. For example, it could be used to predict viral infections in transplant patients and other people with weakened immune systems and enable timely treatment. "We believe this test has great potential. It could, for example, also be used to check if a vaccination has been successful. And it will promote research on the connections between infections, auto-immune diseases and allergies," adds Moosmann.