Electron microscope image of porous graphene-based structure created by diffusion driven layer-by-layer assembly (Kyoto University)
17 October 2014. Materials scientists at Kyoto University in Japan developed a new process that simplifies the building of three-dimension structures with graphene, a light, strong, conductive material with many industrial and commercial applications. Franklin Kim and Jianli Zou from Kyoto’s Institute for Integrated Cell-Material Sciences published their findings yesterday in the journal Nature Communications (paid subscription required).
Graphene is a material closely related to graphite like that used in pencils, but consists of only a single layer of carbon atoms arrayed in a hexagonal mesh pattern. The material is very light, strong, chemically stable, and can conduct both heat and electricity, with applications in fields such as electronics, energy, and health care.
The thin, single-atomic structure that makes graphene a desirable material also makes it difficult to piece together into 3-D structures needed for practical use, which hampers the advance of graphene into commercial applications. Stacking graphene layers, for example, causes the nanoscale sheets to lose their unique individual properties. Current methods for addressing this problem, say the authors, are costly and time consuming.
Kim and Zou sought a simple and scalable method for assembling graphene sheets that can be adapted to commercial and industrial enterprises. The researchers applied a chemical process known as interfacial complexation, where layers of negatively-charged graphene oxide sheets are interspersed with a positively-charged polymer. The polymer in this case is polyethylenimine, a compound used in detergents, adhesives, inks, dyes, and cosmetics, as well as a number of industrial processes.
Putting the opposite-charged layers of graphene oxide and polyethylenimine into contact forms a stable composite layer. “Interestingly, the polymer could continuously diffuse through the interface, and induce additional reactions” says Zou in a university statement, “which allowed the graphene-based composite to develop into thick multi-layered structures.”
The multi-layered structures, say the authors are robust and can be designed with various porosity, from ultra-light to extremely dense, by adjusting the input properties and conditions. The process can be scaled easily for producing large-area films with patterns, or into free-standing shapes for energy generation or storage, such as in batteries or supercapacitors.
Kim adds that the process can be applied to more than just graphene, noting “we strongly believe that the new technique will be able to serve as a general method for the assembly of a much wider range of nanomaterials.”
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16 October 2014. Nine in 10 children and adults in early-stage clinical trials of a personalized therapy harnessing the patients’ immune systems achieved full remission of their acute lymphoblastic leukemia. The findings of the team from University of Pennsylvania and Children’s Hospital of Philadelphia are reported today in New England Journal of Medicine (paid subscription required).
The trials tested a personalized therapy code-named CTL019 with 30 patients having relapsed or unresponsive cases of acute lymphoblastic leukemia, a cancer of blood and bone marrow. The disease progresses quickly, making an overabundance of immature lymphocytes, a type of white blood cell. It is also the most common type of cancer among children, although it can also affect adults.
The process to make CTL019 starts with an individual’s blood cells and separates out T cells, white blood cells used by the immune system to fight invading pathogens, then reprograms the T cells with genetic engineering to find and kill cancer cells. The engineered T cells then become hunter cells, containing a protein known as chimeric antigen receptor that acts like an antibody. These hunter cells are infused back into the patient, seeking out and binding to a protein called CD19 found on the surface of B cells — another type of white blood cell — associated with several types of leukemia.
Among the properties programmed into CTL019 is the ability of hunter cells to quickly multiply and accumulate to battle the cancerous cells. The authors, led by pediatrics professor Stephan Grupp of Children’s Hospital, say their tests show some 10,000 hunter cells are produced for each engineered T cell received by patients.
The trials enrolled 25 patients, ages 5 to 22, at Children’s Hospital and 5 adult patients, ages 26 to 60, at University of Pennsylvania. “The patients who participated in these trials had relapsed as many as four times, including 60 percent whose cancers came back even after stem cell transplants,” says Grupp in a hospital statement. “Their cancers were so aggressive they had no treatment options left.”
The researchers began giving the CTL019 infusions two years ago. Of the 30 patients receiving these personalized infusions, 27 or 90 percent, achieved complete remission. Some 78 percent of the patients survived at least 6 months after the treatments. Of the original patients, 19 remain in remission, 15 of whom received only the CTL019 therapy, while 5 others sought out other therapies, including stem cell transplants. Also of the original patients, 7 relapsed between 6 weeks and 8.5 months after the infusions, although 3 of the relapsed patients developed a different form of leukemia, one where the CD19 protein is not expressed, thus it would not have been helped by the CTL019 therapy.
All of the patients receiving CTL019 experienced an adverse reaction a few days after the infusions called a cytokine release syndrome. While these reactions cause flu-like symptoms, they’re considered an indicator of hunter cells’ progress in fighting the cancer cells. However, nine patients developed severe cytokine release syndrome reactions requiring treatment with immunosuppressant drugs and steroids. All of the patients fully recovered from these reactions.
The pharmaceutical company Novartis is licensing the immunotherapy technology, under an agreement reached two years ago with University of Pennsylvania. In July 2014, CTL019 received breakthrough therapy status from the U.S. Food and Drug Administration, which provides expedited review for new therapies treating serious conditions and where the treatments are shown to be an improvement over current methods.
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Mockup of surgical robot designed to treat epilepsy (Vanderbilt University)
16 October 2014. Engineers at Vanderbilt University in Nashville are building a robot for epilepsy surgery guided by MRI scans and designed to be less invasive than current surgical methods. The team from Vanderbilt, with colleagues from Georgia Tech and Milwaukee School of Engineering, are demonstrating a prototype of the device this week at the Fluid Power Innovation and Research Conference in Nashville.
The project, from the lab of engineering professor Eric Barth, aims to provide a more precise surgical treatment for severe cases of epilepsy that now involve a risky procedure drilling a hole into the skull and going deep into the brain. Epilepsy is a neurological condition where nerve cell signals in the brain are disturbed, causing seizures that can range from blank stares to uncontrolled convulsions and loss of consciousness. The disorder can arise from genetic causes, as well as strokes — the leading cause of epilepsy for people over the age of 35 — and head trauma.
Surgery is a treatment option for difficult-to-control cases, and when the area of the brain causing the seizures is well defined and not interfering with vital functions. More complex types of surgery may be needed when the part of the brain causing seizures can’t be removed, and multiple incisions in the brain are needed to keep the disorder from spreading. Because a part of the brain often involved with epilepsy is the hippocampus, located in the temporal lobe at the base of the brain, surgeons must probe deep into the brain to get access to it.
The Vanderbilt device, designed with neurologists at the university, aims to make the surgery less invasive, by accessing the hippocampus through the cheek, rather than the skull, sharply reducing the distance to the target. Incisions are made with a small (1.14 millimeter), curved needle and guided by MRI scans. A curved needle is required since a straight needle cannot reach the target region.
The device is configured to work inside an MRI scanner, with the needle made of a nickel-titanium alloy that can operate in an MRI. The needle fits into a series of nested tubes, and can change shape and be steered through the brain, one millimeter at a time, powered by compressed air. An electrode in the device activates a radio-frequency signal for removing the targeted brain cells.
David Comber, a Vanderbilt graduate student who performed much of the design work and one the demonstrators at this week’s conference, says tests on models in the lab show the needle’s accuracy is within 1.18 millimeters, considered sufficient for this kind of surgery. Barth says the next step in the device’s development is testing with cadavers.
A continuing concern with medical advances is the cost of new therapies. The team developing the robotic device says it is designed to be built with three-dimensional printing, to keep its costs under control. Among the team members are experts in additive manufacturing, an industrial form of 3-D printing, at Milwaukee School of Engineering.
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Ian Hunter (Mass. Institute of Technology)
15 October 2014. Portal Instruments Inc., a new enterprise developing needless injections for biologic therapies and other medications, raised $11 million in its first round of venture funding. Financing for the Cambridge, Massachusetts company was led by the Sunrise division of drug maker Sanofi, venture capital company PBJ Capital, and an unnamed medical device manufacturer in the U.S.
Portal Instruments is commercializing the research of MIT engineering professor Ian Hunter, who developed a needle-free injection technology. Hunter’s lab says the technology employs an electromagnetic actuator that allows for calibrating delivery of drugs based on the nature and volume of the payload and depth of the injection under the skin. Current needle-free injection techniques with springs or compressed gases use a single-jet delivery with no control over the pressure applied to the drug, which the lab says at high velocities can damage large-protein protein molecules.
The company has an exclusive license from MIT for Hunter’s drug delivery technology. The invention first delivers a high-speed pulse to break the skin and inject the drug to the desired depth, followed by a lower-speed and gentler delivery of the drug payload, which helps protect formulations sensitive to high pressure.
Hunter’s lab says it is conducting feasibility tests of the technology with vaccines and biologic therapies delivered in various kinds of tissue and organs. Portal says the technology is suited for administering biologic therapies that can be viscous in consistency.
Sanofi’s Sunrise division, the funding round leader, seeks out partners to develop new kinds of life science products and co-invests in early stages rather than licensing technologies directly for internal development. Portal Instruments is the third investment for Sunrise, joining life-science start-ups WarpDrive Bio and MyoKardia.
“Portal Instruments provides us with a unique opportunity to deliver medicines in formulations that are currently not possible with needle-based devices in a highly controllable needle-free drug delivery system,” says Katherine Bowdish, who heads the Sunrise division, in a company statement. “For patients this may allow them to choose a way to take their medicines if they prefer not to have a needle-based device, or to choose needle-free self-administration at home of some medicines typically delivered in centralized health care facilities.”
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Constance Cepko (Harvard Medical School)
14 October 2014. Astellas Pharma Inc. in Tokyo is collaborating with a genetics and ophthalmology lab at Harvard University to discover more about the onset of the eye disease retinitis pigmentosa and identify therapy targets. Financial details of the three-year deal with Harvard were not disclosed.
Retinitis pigmentosa is a family of inherited eye disorders that result in damage to the retina, specifically breakdown and failure of photoreceptor cells in the retina leading to progressive vision loss. The disease takes several forms, but it generally results in failure of photoreceptor cells detecting light and color, and helping eyes see in dim light. As a result, people with retinitis pigmentosa may experience symptoms such as night blindness and loss of peripheral vision. The organization Research to Prevent Blindness says some 100,000 people in the U.S. have retinitis pigmentosa.
The collaboration engages the lab of Constance Cepko, a professor of genetics and ophthalmology at Harvard Medical School. Cepko’s lab conducts research on the role of genetics in eye disorders, including work on genetic causes of photoreceptor cell loss and design of gene therapies to address these disorders. The lab is also studying use of benign viruses — those not causing disease — to trace nerve cell pathways in the eyes.
For this partnership, Cepko and colleagues will harness adeno-associated viruses, benign viruses for delivering gene therapies, to identify and verify genes associated with prolonging healthy vision among people inheriting retinitis pigmentosa. If the studies by Cepko’s lab lead to promising treatment options, Astellas will negotiate an exclusive license of the technologies for further development and commercialization.
The deal with Harvard is one of the first collaborations generated by Astellas’s Innovation Management division that started in October 2013. The division, says Astellas, establishes partnerships with labs outside the company to find opportunities in preclinical research.
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14 October 2014. Raze Therapeutics, a biotechnology company designing cancer therapies that stop mechanisms feeding the growth of cancer cells, raised $24 million in its first round of venture financing. The funding round was led Atlas Venture — that co-founded Raze and provided some of its seed capital — as well as MPM Capital Management, MS Ventures, Partners Innovation Fund, Astellas Venture Management, and the pharmaceutical company Novartis.
The company, based in Cambridge, Massachusetts, is building a platform to find and develop therapies that address early mechanisms in the body feeding the aggressive growth of cancer cells, both for solid tumors and blood-related cancers. Raze is targeting a specific type of cellular support known as one-carbon metabolism that the company’s scientific founders say is important to uncontrolled growth of cancer cells, and up to now, not fully appreciated for its role.
One-carbon metabolism’s function in cancer is to drive the accumulation of biomass in tumors, triggered by malfunctioning gene expression or genetic mutations. This function feeds the mitochondria or energy reservoirs of adult cells that divide independently of the cell’s replications. Raze’s platform targets early proteins that support one-carbon metabolism in specific cancer cells, combining biochemistry and data mining to identify biomarkers for therapy targets, then developing drugs to break this mechanism feeding cancer growth.
Raze Therapeutics was founded by cell biologists Vamsi Mootha at Harvard Medical School, Joshua Rabinowitz of Princeton University, and David Sabitini at MIT’s Whitehead Institute, all of whom serve as scientific advisors. Their expertise covers cell growth and metabolism, as well as computational tools to reveal underlying molecular processes. Peter Barrett of Atlas Venture co-founded the company, and now serves as its board chair. Jason Rhodes, also an Atlas Venture partner, is Raze’s acting CEO.
Atlas Venture invests in early stage technology and life science enterprises, and is backing 23 other life science companies in the U.S. and Europe. The firm announced earlier this month it plans to split into two companies, one in life sciences (that keeps the Atlas name) and the other for information technology, with separate investment funds in each company.
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Guido Franzoso (Imperial College London)
13 October 2014. Medical researchers at Imperial College London in the U.K. developed an experimental drug that in lab and animal tests kills multiple myeloma cancer cells without the toxic side effects of other cancer drugs. The team led by Imperial medical professor Guido Franzoso published its findings today in the journal Cancer Cell, with a clinical trial of the new drug expected to begin by the end of next year. In addition, a spin-off company was formed to commercialize the research.
Multiple myeloma is a cancer of the plasma cells, white blood cells help fight infections by making antibodies that recognize invading germs. The disorder causes cancerous cells to accumulate in the bone marrow, crowding out healthy plasma cells. Instead of antibodies, the malfunctioning cancer cells produce abnormal proteins that cause kidney problems. American Cancer Society expects some 24,000 cases of multiple myeloma to occur in the U.S. this year, causing more than 11,000 deaths.
The new drug tested by Franzoso and colleagues, code-named DTP3, addresses a property that enables cancer cells to keep multiplying well beyond normal lifetimes. A protein called nuclear factor kappa B, known to have a role in inflammation and immune systems, also contributes to cancer growth by extending the lifetimes of cancer cells. Developing therapies that address this protein, however, is difficult since it plays a role in supporting both healthy and cancerous cells, and directly targeting the protein can lead to toxic side effects.
The Imperial team — with colleagues elsewhere in the U.K., Europe, and the U.S. — looked for a target in the process between nuclear factor kappa B and cancer cells, which would interrupt signals feeding cancer cells, but not healthy cells. The researchers discovered a set of interacting proteins identified as GADD45-beta and MKK7 that keeps cancer cells alive. The team then screened some 20,000 molecules for activity against these proteins that led to two molecules that disrupt GADD45-beta/MKK7, and after refinements, the peptide-based candidate DTP3.
In their lab tests, researchers found DTP3 disrupts GADD45-beta/MKK7 proteins and kills multiple myeloma cells about as effectively as the current cancer drug bortezomib, marketed as Velcade by Millennium Pharmaceuticals. The tests showed as well DTP3 is 100 times better able to target cancer rather than healthy cells, thus with far less toxicity. In addition, the team found DTP3 kills multiple myeloma cancer cells grafted in lab mice, with no apparent side effects.
The researchers plan to take DTP3 into an early-stage clinical trial and received £3.9 million ($6.3 million) from the Medical Research Council, a science funding agency in the U.K., to fund the work through next year. A spin-off company, Kesios Therapeutics Ltd., has been formed as well to commercialize the research on DTP3. The company received last week equity seed financing of £1.85 million ($3 million) from Imperial’s technology transfer fund to establish the business and begin operations.
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These glass slides were dipped in blood to demonstrate the effectiveness of the tethered–liquid perfluorocarbon or TLP coating. While blood sticks to the untreated slide on the left, the slide treated with TLP on the right emerges entirely clear. (Wyss Institute, Harvard University)
13 October 2014. Engineers and medical researchers at Harvard University developed a material to coat tubes in medical devices that repels blood, preventing clots from forming and reducing the need for blood-thinning drugs. The new material from Harvard’s Wyss Institute for Biologically Inspired Engineering and collaborators at affiliated labs and hospitals is described in an article published yesterday in the journal Nature Biotechnology (paid subscription required).
Blood clots and infections are concerns for people needing dialysis or catheter-based treatments, which can cause serious complications for people already with significant medical burdens. Preventing blood clots when using these devices often requires taking anticoagulants or blood-thinners, which can have adverse side-effects, such as excessive bleeding.
The Wyss team adapted a technology developed by Joanna Aizenberg, one its researchers and a senior author of the article, called Slippery Liquid-Infused Porous Surfaces or Slips, that creates a surface highly repellent to foreign matter. Slips is inspired in part by carnivorous pitcher plants that trap insects in a slippery inner chamber from which they cannot climb out. “Traditional Slips uses porous, textured surface substrates to immobilize the liquid layer,” says Aizenberg in a university statement, “whereas medical surfaces are mostly flat and smooth. So we further adapted our approach by capitalizing on the natural roughness of chemically modified surfaces of medical devices.”
The researchers had another requirement for adapting Slips to medical devices, namely to use materials already approved by the U.S. Food and Drug Administration, to speed adoption by industry. Their solution binds two types of perfluorocarbons: a layer of perfluorocarbon similar to Teflon, with a liquid perfluorocarbon now used clinically to help infants with breathing difficulties. Perfluorocarbons are twice as dense as water and can dissolve gases like oxygen and carbon dioxide.
The team calls this new material tethered–liquid perfluorocarbon or TLP, which they tested in the lab on 20 different surfaces. The results show the super-slippery TLPs prevent the attachment of fibrins and platelets that cause blood clots, as well as the formation of biofilms, colonies of bacteria associated with medically-related infections.
In one of the tests, researchers tried to grow Pseudomonas aeruginosa bacteria in medical tubing coated with TLP for 6 weeks, and found less than 1 in a billion bacteria were able to adhere to the tube surface. An estimated 51,000 healthcare-associated P. aeruginosa infections occur in the U.S. each year, according to the CDC, with 13 percent of those infections involving antibiotic resistant bacteria.
In addition, the team implanted pigs with medical tubing similar to those in medical devices, and coated with TLP. The tests with pigs showed the coated tubing maintains high blood flow rates without the need for anticoagulant drugs.
The following video tells more about TLPs, including a test with a live gecko.
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Microscopic view of the hepatitis C virus (VA.gov)
Updated 11 October 2014. The U.S. Food and Drug Administration approved a drug combining a new compound, ledipasvir, with the existing drug sofosbuvir to treat hepatitis C genotype 1, the most common form of the disease. The combination of ledipasvir and sofosbuvir is developed and marketed under the brand name Harvoni by Gilead Sciences Inc. in Foster City, California.
Hepatitis C is a viral infection affecting the liver, with some 3.2 million infected with the virus in the U.S., according to Centers for Disease Control and Prevention. The disease is transmitted through contact with infected blood; intravenous drug users sharing needles are among those at the highest risk. The virus causes inflammation of the liver and can lead to scarring and poor liver function (cirrhosis) over many years. Because there are no symptoms early on, many people with hepatitis C infections do not get treatment until more serious complications occur.
There are 6 known genetic types of hepatitis C, with genotype 1 accounting for 75 percent of all cases in the U.S. Genotype 1, however, is the least likely of the major types of the disease to respond to treatment.
Harvoni is the first drug to combine ledipasvir with sofosbuvir to treat hepatitis C, genotype 1. FDA approved sofosbuvir, also made by Gilead Sciences and marketed under the brand name Sovaldi in December 2013 to treat hepatitis C. Sovaldi, like Harvoni, is a once-a-day pill, and is taken with other drugs, such as ribavirin.
Harvoni, however, was tested in clinical trials, and found as effective when taken alone as with ribavirin. FDA cited three sets of late-stage clinical trials in its approval decision that show Harvoni enabled 94 percent of hepatitis C patients to be free of the virus in their blood after 8 weeks, and 96 to 99 percent virus-free after 12 weeks. Patients who underwent previous therapies required 24 weeks to be virus-free.
FDA reviewed Harvoni under its priority review program, which grants expedited review for treatments showing a substantial improvement over current drugs for serious or life-threatening conditions. The agency also called the drug a breakthrough therapy, thus also qualifying for expedited attention.
Forbes magazine reports today that Harvoni, like Sovaldi, will be an expensive drug, costing $94,500 for a 12-week course of treatment. Sovaldi costs $84,000 for a full treatment. The magazine says 35 states require prior authorization for Sovaldi, including a liver biopsy to determine severity of disease, before Medicaid authorities in those states will approve payments for the drug.
Update: 11 October 2014. The New York Times points out this morning that most people taking Harvoni will need only the 8-week course of treatment, making its cost over that time $63,000, less than the $84,000 needed for 12 weeks of Sovaldi. The cost per dose of Harvoni, $1,125, is still more than $1,000 for Sovaldi.
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Human stem cell derived beta cells in mice (Doug Melton, Harvard University)
9 October 2014. Researchers at Harvard University developed a technique that enables embryonic stem cells to transform into large quantities of insulin-producing beta cells found in the pancreas, a key step in developing a treatment for type 1 diabetes. The team led by biologist Douglas Melton, co-director of the university’s Stem Cell Institute, published its findings today in the journal Cell (paid subscription required).
Beta cells in the pancreas, when functioning properly, produce insulin, a hormone that helps the body store and process glucose provided by food in the diet. People with type 1 diabetes, a condition where the body’s immune system is tricked into destroying beta cells. Some 3 million people in the U.S. have type 1 diabetes, including many children and young adults, who need to replace their insulin supply daily through injections or devices such as insulin pumps.
Melton and colleagues designed a culturing protocol for transforming human embryonic stem cells into pancreatic and endocrine progenitor cells, and then into beta cells. Their techniques enabled the team to generate hundreds of millions of beta cells in the lab that perform the same insulin-secreting functions, responding to glucose as normal mature beta cells. Tests of the beta cells show their genes express similarly to normal beta cells.
The researchers then implanted the lab-produced beta cells in mice where the cells secreted insulin in response to glucose as they had done in lab cultures. In addition, the team induced a diabetic state in lab mice, and found transplants of the lab-produced beta cells relieved hyperglycemia, a high blood glucose condition, in the test mice. Harvard says Melton’s lab is also testing stem-cell derived beta cells in monkeys.
For Melton, the issue of type 1 diabetes is personal. The university says his son and daughter were diagnosed with the disorder as children, and he made finding a cure the goal of his career. Melton is collaborating as well with MIT biomedical engineer Daniel Anderson to develop a device that protects the 150 million implanted beta cells from immune-system attack. Preclinical tests of the device with lab mice indicate the device can protect the cells for months while they continue to produce insulin.
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