North Carolina State University researchers have developed a technique to improve the characteristics of engineered tissues by using ultrasound to align living cells during the bio-fabrication process. "We've reached the point where we are able to create medical products, such as knee implants, by printing living cells," says Rohan Shirwaiker, corresponding author of a paper on the work and an associate professor in NC State's Edward P. Fitts Department of Industrial & Systems Engineering. "But one challenge has been organizing the cells that are being printed, so that the engineered tissue more closely mimics natural tissues. "We've now developed a technique, called ultrasound-assisted biofabrication (UAB), which allows us to align cells in a three-dimensional matrix during the bioprinting process. This allows us to create a knee meniscus, for example, that is more similar to a patient's original meniscus. To date, we've been able to align cells for a range of engineered musculoskeletal tissues." To align the cells, the researchers built an ultrasound chamber that allows ultrasonic waves to travel across the area where a bioprinter prints living cells. These ultrasonic waves travel in one direction and are then reflected back to their source, creating a "standing ultrasound wave." The soundwaves effectively herd the cells into rows, which align with areas where the ultrasound waves and the reflected waves cross each other. "We can control the alignment characteristics of the cells by controlling the parameters of the ultrasound, such as frequency and amplitude," Shirwaiker says. To demonstrate the viability of the UAB technique, the researchers created a knee meniscus, with the cells aligned in a semilunar arc - just as they are in a natural meniscus. "We were able to control the alignment of the cells as they were printed, layer by layer, throughout the tissue," Shirwaiker says. "We've also shown the ability to align cells in ways that are particularly important for other orthopedic soft tissues, such as ligaments and tendons." The researchers also found that some combinations of ultrasound parameters led to cell death. "This is important, because it gives us a clear understanding of both what we can do to improve tissue performance and what we need to avoid in order to preserve living cells," Shirwaiker says. To that end, the researchers have created computational models that allow users to predict the performance of any given set of parameters before beginning the biofabrication process. One other benefit of the UAB technique is that it is relatively inexpensive. "There's a one-time cost for setting up the ultrasound equipment - which can use off-the-shelf technology" Shirwaiker says. "After that, the operating costs for the ultrasound components are negligible. And the UAB technique can be used in conjunction with most existing bioprinting technologies. "We have a patent pending on the UAB technique, and are now looking for industry partners to help us explore commercialization," Shirwaiker says.
Biomedical engineers at Duke University have developed an automated process that can trace the shapes of active neurons as accurately as human researchers can, but in a fraction of the time. This new technique, based on using artificial intelligence to interpret video images, addresses a critical roadblock in neuron analysis, allowing researchers to rapidly gather and process neuronal signals for real-time behavioral studies. The research appeared this week in the Proceedings of the National Academy of Sciences. To measure neural activity, researchers typically use a process known as two-photon calcium imaging, which allows them to record the activity of individual neurons in the brains of live animals. These recordings enable researchers to track which neurons are firing, and how they potentially correspond to different behaviors. While these measurements are useful for behavioral studies, identifying individual neurons in the recordings is a painstaking process. Currently, the most accurate method requires a human analyst to circle every 'spark' they see in the recording, often requiring them to stop and rewind the video until the targeted neurons are identified and saved. To further complicate the process, investigators are often interested in identifying only a small subset of active neurons that overlap in different layers within the thousands of neurons that are imaged. This process, called segmentation, is fussy and slow. A researcher can spend anywhere from four to 24 hours segmenting neurons in a 30-minute video recording, and that's assuming they're fully focused for the duration and don't take breaks to sleep, eat or use the bathroom. In contrast, a new open source automated algorithm developed by image processing and neuroscience researchers in Duke's Department of Biomedical Engineering can accurately identify and segment neurons in minutes. "As a critical step towards complete mapping of brain activity, we were tasked with the formidable challenge of developing a fast automated algorithm that is as accurate as humans for segmenting a variety of active neurons imaged under different experimental settings," said Sina Farsiu, the Paul Ruffin Scarborough Associate Professor of Engineering in Duke BME. "The data analysis bottleneck has existed in neuroscience for a long time -- data analysts have spent hours and hours processing minutes of data, but this algorithm can process a 30-minute video in 20 to 30 minutes," said Yiyang Gong, an assistant professor in Duke BME. "We were also able to generalize its performance, so it can operate equally well if we need to segment neurons from another layer of the brain with different neuron size or densities." "Our deep learning-based algorithm is fast, and is demonstrated to be as accurate as (if not better than) human experts in segmenting active and overlapping neurons from two-photon microscopy recordings," said Somayyeh Soltanian-Zadeh, a PhD student in Duke BME and first author on the paper. Deep-learning algorithms allow researchers to quickly process large amounts of data by sending it through multiple layers of nonlinear processing units, which can be trained to identify different parts of a complex image. In their framework, this team created an algorithm that could process both spatial and timing information in the input videos. They then 'trained' the algorithm to mimic the segmentation of a human analyst while improving the accuracy. The advance is a critical step towards allowing neuroscientists to track neural activity in real time. Because of their tool's widespread usefulness, the team has made their software and annotated dataset available online. Gong is already using the new method to more closely study the neural activity associated with different behaviors in mice. By better understanding which neurons fire for different activities, Gong hopes to learn how researchers can manipulate brain activity to modify behavior.
A healthy adult makes about 2 million blood cells every second, and 99 percent of them are oxygen-carrying red blood cells. The other one percent are platelets and the various white blood cells of the immune system. How all the different kinds of mature blood cells are derived from the same "hematopoietic" stem cells in the bone marrow has been the subject of intense research, but most studies have focused on the one percent, the immune cells. "It's a bit odd, but because red blood cells are enucleated and therefore hard to track by genetic markers, their production has been more or less ignored by the vast number of studies in the past couple of decades," said Camilla Forsberg, professor of biomolecular engineering in the Baskin School of Engineering at UC Santa Cruz. In a new study, published March 21 in Stem Cell Reports, Forsberg's lab overcame technical obstacles to provide a thorough accounting of blood cell production from hematopoietic stem cells. Their findings are important for understanding disorders such as anemia, diseases of the immune system, and blood cancers such as leukemias and lymphomas. "We're trying to understand the balance of production of blood cells and immune cells, which goes wrong in many kinds of disorders," Forsberg said. The process by which hematopoietic stem cells give rise to mature blood cells involves multiple populations of progenitor cells that become progressively more committed to a specific "fate" as they develop into fully mature cells. A major fork in the road is between "lymphoid progenitors," which give rise to white blood cells called lymphocytes, and "myeloid progenitors," which give rise to other kinds of white blood cells, as well as red blood cells and platelets. The majority of cells in the bone marrow are in the myeloid lineage. A key finding of the new study is that all progenitor cells with myeloid potential produce far more red blood cells than any other cell type. This was surprising because many previous studies in which progenitor cells were grown in cell cultures ("in vitro") found they had limited capacity to produce red blood cells and platelets. Forsberg said those results now appear to be an artifact of the culture conditions. "It's been hard to make sense of a lot of those experiments, because we know our bodies need to make a lot of red blood cells and platelets," she said. "Our results show that these progenitor cells retain a lot of red blood cell potential. In fact, we propose that red blood cell production is the default pathway." In experiments led by first author Scott Boyer, a graduate student in Forsberg's lab, researchers transplanted different progenitor cell populations into mice and tracked the production of red blood cells as well as platelets (the second largest component of blood) and immune cells. Boyer was also able to transplant single progenitor cells and then identify the blood and immune cells it produced. By quantifying the numbers of mature blood cells produced from transplanted progenitors, the researchers were able to show that red blood cells were by far the most abundant cell type produced by every type of progenitor cell, with the exception of lymphoid progenitors. Their findings led to the development of a model of hematopoietic differentiation that focuses on red blood cells as the default pathway for all myeloid progenitors. In addition to Forsberg and Boyer, the coauthors of the paper include Smrithi Rajendiran, Anna Beaudin, Stephanie Smith-Berdan, Praveen Muthuswamy, Jessica Perez-Cunningham, Eric Martin, Christa Cheung, Herman Tsang, and Mark Landon, all at the UC Santa Cruz Institute for the Biology of Stem Cells. This work was supported by the National Institutes of Health and the California Institute for Regenerative Medicine.
▣ CATEGORY OF COMPANIES (NACE Rev.2) Manufacture of basic pharmaceutical products Manufacture of basic pharmaceutical products and pharmaceutical preparations Manufacture of pharmaceutical preparations
The vast majority of cancer deaths occur due to the spread of cancer from one organ to another, which can happen either through the blood or the lymphatic system. However, it can be tricky to detect this early enough. Researchers at Tohoku University have developed a new method that would allow doctors to detect cancers in the lymph nodes while they are still small, before they travel to other parts of the body. This can greatly increase the chances of a successful treatment. There aren't many imaging techniques that can detect tumors in lymph nodes before they grow too large, especially in smaller nodes. Biopsies of lymph nodes is a possible option, but it can often give false negative results. So the team wanted to come up with a new method that would accurately detect the earliest stages of a cancer moving to another part of the body, using a technique called x-ray microcomputed tomography (micro-CT) (imaging supplies in the catalogue of MEDICA 2018). The team tested their new method on mice with breast cancer cells inserted into their lymph nodes. They injected a contrast agent at a slow, steady pace into the lymph nodes upstream of those carrying the cancer cells. As the contrast agent made its way through the lymphatic system, the researchers were able to map out its movement using micro-CT. Initially, the researchers did not observe any change in the flow of the contrast agent. However, after 28 days of injecting the cancer cells into the lymph nodes, they had divided and grown to a point where they blocked the flow of the contrast agent, creating empty pockets in the scan that did not have any contrast agent. By comparing the shape of the lymph node and the areas that contained the contrast agent, the researchers were able to get a clear picture of the presence of cancer cells there. Next, the researchers would like to hone in on better contrast agents that would offer a clearer, more precise picture of how cancer cells are moving around the lymphatic system. In the future, this technique could be an effective way to detect tumors early before they spread around the body, saving many lives and adding one more tool that doctors can turn to in their fight against cancer.
The debilitating side effects of radiotherapy could soon be a thing of the past thanks to a breakthrough by University of South Australia (UniSA) and Harvard University researchers. UniSA biomedical engineer Professor Benjamin Thierry is leading an international study using organ-on-a-chip technology to develop 3D models to test the effects of different levels and types of radiation. A microfluidic cell culture chip closely mimics the structure and function of small blood vessels within a disposable device the size of a glass slide, allowing researchers and clinicians to investigate the impact of radiotherapy on the body’s tissues. To date, scientists have relied on testing radiotherapy on cells in a two-dimensional environment on a slide. Professor Thierry, from UniSA’s Future Industries Institute (FII) and the ARC Centre of Excellence in Convergent Bio-Nano Science and Technology (CBNS), says the organ-on-a-chip technology could reduce the need for animal studies and irrelevant invitro work, both of which have major limitations. “An important finding of the study is that endothelial cells grown in the standard 2D culture are significantly more radiosensitive than cells in the 3D vascular network. This is significant because we need to balance the effect of radiation on tumour tissues while preserving healthy ones,” Prof Thierry says. The findings, published in Advanced Materials Technologies, will allow researchers to fully investigate how radiation impacts on blood vessels and – soon – all other sensitive organs. “The human microvasculature (blood vessel systems within organs) is particularly sensitive to radiotherapy and the model used in this study could potentially lead to more effective therapies with fewer side effects for cancer patients,” Prof Thierry says. More than half of all cancer patients receive radiotherapy at least once in the course of their treatment. While it cures many cancers, the side effects can be brutal and sometimes lead to acute organ failure and long-term cardiovascular disease. Prof Thierry’s team, including UniSA FII colleague Dr Chih-Tsung Yang and PhD student Zhaobin Guo, are working in close collaboration with the Royal Adelaide Hospital and Harvard University’s Dana-Farber Cancer Institute with the support of the Australian National Fabrication Facility. “Better understanding the effect of radiotherapy on blood vessels within organs – and more generally on healthy tissues – is important, especially where extremely high doses and types of radiation are used,” Dr Yang says. The researchers’ next step is to develop body-on-chip models that mimic the key organs relevant to a specific cancer type.
The wrist-worn device, called Tingle, was also able to distinguish between behaviors directed toward six different locations on the head. The paper, "Thermal Sensors Improve Wrist-worn Position Tracking," provides preliminary evidence of the device's potential use in the diagnosis and management of excoriation disorder (chronic skin-picking), nail-biting, trichotillomania (chronic hair-pulling), and other body-focused repetitive behaviors (BFRBs). The researchers, led by Arno Klein, Ph.D., Director of Innovative Technologies, Joseph Healey Scholar, and Senior Research Scientist in the Center for the Developing Brain at the Child Mind Institute, collected data from 39 healthy adult volunteers by having them perform a series of repetitive behaviors while wearing the Tingle (find out more about Information and Communication Technology at MEDICA 2018 here). The Tingle was designed by the Institute's MATTER Lab to passively collect thermal, proximity and accelerometer data. Dr. Klein and colleagues found that the thermal sensor data improved the Tingle device's ability to accurately distinguish between a hand's position at different locations on the head, which would be useful in detecting clinically relevant BFRBs. BFRBs are related to a variety of mental and neurological illnesses (find out more about Neurological diagnosis, apparatus and instruments at MEDICA 2018 here), including autism, Tourette Syndrome and Parkinson's Disease. "Body-focused repetitive behaviors can cause significant harm and distress," said Dr. Klein. "Our findings are quite promising because they indicate that the thermal sensors (find out more about Temperature sensors at COMPAMED 2018 here) in devices like the Tingle have potential uses for many different types of hand movement training, in navigation of virtual environments, and in monitoring and mitigating repetitive, compulsive behaviors like BFRBs."
Many types of cancer could be more easily treated if they were detected at an earlier stage. MIT researchers have now developed an imaging system, named "DOLPHIN," which could enable them to find tiny tumors, as small as a couple of hundred cells, deep within the body. In a new study, the researchers used their imaging system, which relies on near-infrared light, to track a 0.1-millimeter fluorescent probe through the digestive tract of a living mouse. They also showed that they can detect a signal to a tissue depth of 8 centimeters, far deeper than any existing biomedical optical imaging technique. The researchers hope to adapt their imaging technology for early diagnosis of ovarian and other cancers that are currently difficult to detect until late stages. "We want to be able to find cancer much earlier," says Angela Belcher, the James Mason Crafts Prof. of Biological Engineering and Materials Science at MIT and a member of the Koch Institute for Integrative Cancer Research, and the newly-appointed head of MIT's Department of Biological Engineering. "Our goal is to find tiny tumors, and do so in a noninvasive way." Existing methods for imaging tumors all have limitations that prevent them from being useful for early cancer diagnosis. Most have a tradeoff between resolution and depth of imaging, and none of the optical imaging techniques can image deeper than about 3 centimeters into tissue. Commonly used scans such as X-ray computed tomography (CT) and magnetic resonance imaging (MRI) can image through the whole body; however, they can't reliably identify tumors until they reach about 1 centimeter in size. Belcher's lab set out to develop new optical methods for cancer imaging several years ago, when they joined the Koch Institute. They wanted to develop technology that could image very small groups of cells deep within tissue and do so without any kind of radioactive labeling. Near-infrared light, which has wavelengths from 900 to 1700 nanometers, is well-suited to tissue imaging because light with longer wavelengths doesn't scatter as much as when it strikes objects, which allows the light to penetrate deeper into the tissue. To take advantage of this, the researchers used an approach known as hyperspectral imaging, which enables simultaneous imaging in multiple wavelengths of light. The researchers tested their system with a variety of near-infrared fluorescent light-emitting probes, mainly sodium yttrium fluoride nanoparticles that have rare earth elements such as erbium, holmium, or praseodymium added through a process called doping. Depending on the choice of the doping element, each of these particles emits near-infrared fluorescent light of different wavelengths. Using algorithms that they developed, the researchers can analyze the data from the hyperspectral scan to identify the sources of fluorescent light of different wavelengths, which allows them to determine the location of a particular probe. By further analyzing light from narrower wavelength bands within the entire near-IR spectrum, the researchers can also determine the depth at which a probe is located. The researchers call their system "DOLPHIN", which stands for "Detection of Optically Luminescent Probes using Hyperspectral and diffuse Imaging in Near-infrared." To demonstrate the potential usefulness of this system, the researchers tracked a 0.1-millimeter-sized cluster of fluorescent nanoparticles that was swallowed and then traveled through the digestive tract of a living mouse. These probes could be modified so that they target and fluorescently label specific cancer cells. "In terms of practical applications, this technique would allow us to non-invasively track a 0.1-millimeter-sized fluorescently-labeled tumor, which is a cluster of about a few hundred cells. To our knowledge, no one has been able to do this previously using optical imaging techniques," Bardhan says.
Thanks to revolutionary developments in stem cell research, scientists can grow mini intestines, livers, lungs and pancreases in the lab. Recently, by growing so-called pluripotent stem cells, they have also been able to do this for kidneys. In their study, the researchers from Utrecht University used adult stem cells, directly from the patient, for the first time. Urine cells also proved to be ideal for this purpose. A mini kidney from the lab doesn't look like a normal kidney. But the simple cell structures share many of the characteristics of real kidneys, so researchers can use them to study certain kidney diseases. "We can use these mini kidneys to model various disorders: hereditary kidney diseases, infections and cancer. This allows us to study in detail what exactly is going wrong", says Hans Clevers, Prof. of Molecular Genetics at Utrecht University and the University Medical Center Utrecht, and group leader at the Hubrecht Institute. "This helps us to understand the workings of healthy kidneys better, and hopefully, in the future, we will be able to develop treatments for kidney disorders." Kidney patients who undergo a transplant are at risk of contracting a viral infection. Unfortunately, at the moment there is still no effective treatment for this. "In the lab, we can give a mini kidney a viral infection which some patients contract following a kidney transplant," says Prof. of Experimental Nephrology at UMC Utrecht, Marianne Verhaar. "We can then establish whether this infection can be cured using a specific drug. And we can also use mini kidneys created from the tissue of a patient with kidney cancer to study cancer." Verhaar explains that she collaborates with medics, researchers and technical experts at a single location in Utrecht: the Regenerative Medicine Centre Utrecht. "Collaborating in this way has made a huge difference to our research. We hope that, together, we can improve treatments for kidney patients. In the long term, we hope to be able to use mini kidneys to create a real, functioning kidney - a tailor-made kidney - too. But that's still a long way."
A new ultrasensitive diagnostic device invented by researchers at the University of Kansas, The University of Kansas Cancer Center and KU Medical Center could allow doctors to detect cancer quickly from a droplet of blood or plasma, leading to timelier interventions and better outcomes for patients. The “lab-on-a-chip” for “liquid biopsy” analysis, reported today in Nature Biomedical Engineering, detects exosomes — tiny parcels of biological information produced by tumor cells to stimulate tumor growth or metastasize. “Historically, people thought exosomes were like ‘trash bags’ that cells could use to dump unwanted cellular contents,” said lead author Yong Zeng, Docking Family Scholar and associate professor of chemistry at KU. “But in the past decade, scientists realized they were quite useful for sending messages to recipient cells and communicating molecular information important in many biological functions. Basically, tumors send out exosomes packaging active molecules that mirror the biological features of the parental cells. While all cells produce exosomes, tumor cells are really active compared to normal cells.” The new lab-on-a-chip’s key innovation is a 3D nanoengineering method that mixes and senses biological elements based on a herringbone pattern commonly found in nature, pushing exosomes into contact with the chip’s sensing surface much more efficiently in a process called “mass transfer.” “People have developed smart ideas to improve mass transfer in microscale channels, but when particles are moving closer to the sensor surface, they’re separated by a small gap of liquid that creates increasing hydrodynamic resistance,” Zeng said. “Here, we developed a 3D nanoporous herringbone structure that can drain the liquid in that gap to bring the particles in hard contact with the surface where probes can recognize and capture them.” Zeng compared the chip’s nanopores to a million little kitchen sinks: “If you have a sink filled with water and many balls floating on the surface, how do you get all the balls in contact with the bottom of the sink where sensors could analyze them? The easiest way is to drain the water.” To develop and test the pioneering microfluidic device, Zeng teamed with a tumor-biomarker expert and KU Cancer Center Deputy Director Andrew Godwin at the KU Medical Center’s Department of Pathology & Laboratory Medicine, as well as graduate student Ashley Tetlow in Godwin’s Biomarker Discovery Lab. The collaborators tested the chip’s design using clinical samples from ovarian cancer patients, finding the chip could detect the presence of cancer in a minuscule amount of plasma. “Our collaborative studies continue to bear fruit and advance an area crucial in cancer research and patient care — namely, innovative tools for early detection,” said Godwin, who serves as Chancellor's Distinguished Chair and Endowed Professor in Biomedical Sciences and professor and director of molecular oncology, pathology and laboratory medicine at KU Medical Center. “This area of study is especially important for cancers such as ovarian, given the vast majority of women are diagnosed at an advanced stage when, sadly, the disease is for the most part incurable.” What’s more, the new microfluidic chips developed at KU would be cheaper and easier to make than comparable designs, allowing for wider and less-costly testing for patients. “What we created here is a 3D nanopatterning method without the need for any fancy nanofabrication equipment — an undergraduate or even a high school student can do it in my lab,” Zeng said. “This is so simple and low-cost it has great potential to translate into clinical settings. We’ve been collaborating with Dr. Godwin and other research labs at The KU Cancer Center and the molecular biosciences department to further explore the translational applications of the technology.” According to Zeng, with the microfluidic chip’s design now proven using ovarian cancer as a model, the chip could be useful in detecting a host of other diseases. “Now, we’re looking at cell-culture models, animal models, and also clinical patient samples, so we are truly doing some translational research to move the device from the lab setting to more clinical applications,” he said. “Almost all mammalian cells release exosomes, so the application is not just limited to ovarian cancer or any one type of cancer. We’re working with people to look at neurodegenerative diseases, breast and colorectal cancers, for example.” On KU’s Lawrence campus, Zeng worked with a team including postdoctoral fellow Peng Zhang, graduate student Xin Zhou in the Department of Chemistry, as well as Mei He, KU assistant professor of chemistry and chemical engineering. This research was supported by grants from National Institutes of Health, including a joint R21 (CA1806846) and a R33 (CA214333) grant between Zeng and Godwin and the KU Cancer Center’s Biospecimen Repository Core Facility, funded in part by a National Cancer Institute Cancer Center Support Grant (P30 CA168524). Image: The new lab-on-a-chip’s key innovation is a 3D nanoengineering method that mixes and senses biological elements based on a herringbone pattern commonly found in nature, pushing exosomes into contact with the chip’s sensing surface much more efficiently in a process called “mass transfer.”