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Archive - Apr 24, 2017

Exosomes Carrying Pathogen Material Are More Rapidly Taken Up in Lymph Nodes Than Control Exosomes

Exosomes, tiny sub-cellular vesicles smaller than red blood cells, were once thought of as molecular trash bins. And it’s true, these nanoparticles do carry off a cell’s discarded material. But now it is known that exosomes can also include can mRNAs, micro RNAs, and proteins,and that exosomes help to carry out the critical cell-to-cell communication that multicellular organisms depend on for survival. Not only can exosomes communicate and provide transport over long distances – they also happen to be in the ideal size range for lymphatic transport, a concept that has long captivated Dr. Brandon Dixon and Dr. Fred Vannberg, researchers in the Petit Institute for Bioengineering and Bioscience in the Georgia Institute of Technology, and others interested in the future of lymphatic targeted drug delivery systems. Last year (2016), Dr. Dixon and Dr. Vannberg collaborated on a groundbreaking research paper (see link below) in the Nature journal, Scientific Reports, entitled, “Lymphatic Transport of Exosomes As a Rapid Route of Information Dissemination to the Lymph Node.” Their results suggested that exosomes facilitate the rapid exchange of infection-specific information from peripheral tissue to the lymph node, essentially priming the node for an effective innate immune response. The scientists’ latest paper, “TLR-Exosomes Exhibit Distinct Kinetics and Effector Function,” published recently in the same journal (Scientific Reports, online March 14, 2017), digs deeper, making a striking new discovery along the way: Exosomes move with what looks like an increased sense of urgency depending on their payload. “Not only do we find out that these exosomes can inform the node of what kind of specific immune response to initiate – is it viral, or a bacterial infection?

Scientists Show That Increased RNA-Binding Protein GRP8 Results in Longer and More Root Hairs, Leading to Increased Uptake & Transport of Phosphorus, and to Larger Plants

The function of a plant's roots go well beyond simply serving as an anchor in the ground. The roots act as the plant's mouth, absorbing, storing, and channeling water and nutrients essential for survival. Researchers have devoted tremendous effort to engineering plants that are more effective at these tasks in order to develop hardier forms that can withstand drought or low-nutrient conditions. In a new investigation, researchers from the University of Pennsylvania (Penn) have taken another step toward achieving this goal. They identified two proteins that regulate whether a cell in plant roots forms a hair cell, which increases surface area for absorption, or a non-hair cell. Plants that overexpressed one of these regulators thrived despite being deprived of a key nutrient, phosphorus. "Normally plants respond to phosphorus deprivation by becoming smaller, which means less biomass, less food production, and less seed production," said Brian Gregory, Ph.D., an Associate Professor in the Department of Biology in Penn's School of Arts & Sciences and senior author on the paper. "The intriguing thing is, by overexpressing one of these proteins we identify GRP8, we were able to produce plants that don't show this kind of dwarfing nearly as significantly as normal plants under phosphorus starvation. That's the exact phenotype we want." Such plants, which produce more hair cells and thus can more readily absorb water from the soil, could also do well under conditions predicted to be more prevalent under climate change, notably in widespread droughts. The lead author of the work, which was published in the April 24, 2017 issue of Developmental Cell, is Dr. Shawn W. Foley, a recent Ph.D. recipient in the Cell and Molecular Biology Graduate Program of Penn's Perelman School of Medicine.

Wax Worm Caterpillar Found to Degrade Plastic at Rapid Rate; Potential Seen for Biotechnology Solution to Managing Polyethylene Waste on Industrial Scale

Scientists have found that a caterpillar commercially bred for fishing bait has the ability to biodegrade polyethylene: one of the toughest and most used plastics, frequently found clogging up landfill sites in the form of plastic shopping bags. The wax worm, the larvae of the common insect Galleria mellonella, or greater wax moth, is a scourge of beehives across Europe. In the wild, the worms live as parasites in bee colonies. Wax moths lay their eggs inside hives where the worms hatch and grow on beeswax - hence the name. A chance discovery occurred when one of the scientific team, Dr. Federica Bertocchini, an amateur beekeeper, was removing the parasitic pests from the honeycombs in her hives. The worms were temporarily kept in a typical plastic shopping bag that became riddled with holes. Dr. Bertocchini, from the Institute of Biomedicine and Biotechnology of Cantabria (CSIC), Spain, collaborated with colleagues Dr. Paolo Bombelli and Dr. Christopher Howe at the University of Cambridge's Department of Biochemistry to conduct a timed experiment. Approximately 100 wax worms were exposed to a plastic bag from a UK supermarket. Holes started to appear after just 40 minutes, and after 12 hours there was a reduction in plastic mass of 92 mg from the bag. Scientists say that the degradation rate is extremely fast compared to other recent discoveries, such as bacteria reported last year to biodegrade some plastics at a rate of just 0.13mg a day. "If a single enzyme is responsible for this chemical process, its reproduction on a large scale using biotechnological methods should be achievable," said Cambridge's Dr. Bombelli, first author of the study published today (April 24, 2017) in the journal Current Biology.

STING-Activating Nanovaccine Shows Anti-Tumor Efficacy in Multiple Cancer Types in Mice

Researchers from the University of Texas (UT) Southwestern Medical Center have developed a first-of-its-kind nanoparticle vaccine immunotherapy that targets several different cancer types. The nanovaccine consists of tumor antigens – tumor proteins that can be recognized by the immune system – inside a synthetic polymer nanoparticle. Nanoparticle vaccines deliver minuscule particulates that stimulate the immune system to mount an immune response. The goal is to help people’s own bodies fight cancer. “What is unique about our design is the simplicity of the single-polymer composition that can precisely deliver tumor antigens to immune cells while stimulating innate immunity. These actions result in safe and robust production of tumor-specific T cells that kill cancer cells,” said Dr. Jinming Gao, a Professor of Pharmacology and Otolaryngology in UT Southwestern’s Harold C. Simmons Comprehensive Cancer Center. A study outlining this research, and published online on April 24, 2017 in Nature Nanotechnology, reported that the nanovaccine had anti-tumor efficacy in multiple tumor types in mice. The article is titled “A STING-Activating Nanovaccine for Cancer Immunotherapy.” The research was a collaboration between the laboratories of study senior authors Dr. Gao and Dr. Zhijian “James” Chen, Professor of Molecular Biology and Director of the Center for Inflammation Research at UT Southwestern. The Center was established in 2015 to study how the body senses infection and to develop approaches to exploit this knowledge to create new treatments for infection, immune disorders, and autoimmunity. Typical vaccines require immune cells to pick up tumor antigens in a “depot system” and then travel to the lymphoid organs for T cell activation, Dr. Gao said.

Annual ISEV Meeting on Extracellular Vesicles (Including Exosomes) in Toronto May 17-21

The annual meeting of the International Society for Extracellular Vesicles (ISEV 2017) (https://isev.site-ym.com/), will take place from May 17-21 in Toronto, Canada, and will offer an unparalleled opportunity to network with, and learn from, the preeminent leaders in extracellular vesicle (EV) research. To register for this meeting, please click here (https://isev.site-ym.com/page/ISEV2017Registration). The scope and quality of the anticipated scientific exchange make ISEV 2017 the largest and the premier meeting in EV research in the world. This event features five days of the best in vesicle science covering all aspects of basic, clinical, and translational research. The research theme includes diverse areas of science encompassing rare and neglected diseases, infectious disease, coagulation, cancer, neuroscience, cardiovascular studies, immunology, regenerative medicine, virology, parasitology, and more. The overall theme of ISEV 2017 is “Diversity of EV Composition and Function in Disease Diagnosis and Therapeutics.” Amidst growing interest in the promise of EVs in disease detection and treatment, ISEV 2017 will bring scientists and clinicians in medical and biotechnology communities together to translate their research. No other meeting in the world offers the scope, participation level, and thematic focus of ISEV 2017 concentrating and cross-pollinating scientific investigations in the field of disease biomarkers and therapeutic tools by disseminating cutting-edge developments in EV research. Among the plenary speakers scheduled to address the meeting are Clotilde Thery, Ph.D. (Research Director, Institut Curie), Philip Stahl, Ph.D. (Professor Emeritus of Cell Biology and Physiology, Washington University School of Medicine), Thomas Thum M.D., Ph.D. (Professor of Cardiology, Imperial College-London), Jeff Wrana, Ph.D.

Rab32 Protein Connects ER Stress to Mitochondrial Defects in Multiple Sclerosis; Protein Accumulates in Brain Tissue of MS Patients, But Is Virtually Absent in Unaffected Individuals

A new study has made a major new discovery towards possibly finding the cause of multiple sclerosis (MS), potentially paving the way for research to investigate new treatments. Ahead of MS Awareness Week, which starts today (Monday April 24), an international team involving the University of Exeter Medical School (UK) and the University of Alberta (Canada) has discovered a new cellular mechanism-- an underlying defect in brain cells -- that may cause the disease, and mey be a potential hallmark that may be a target for future treatment of the autoimmune disorder. The study was published online on January 23, 2017 in the Journal of Neuroinflammation. The open-access article is titled “Rab32 Connects ER Stress to Mitochondrial Defects in Multiple Sclerosis.” Professor Paul Eggleton, of the University of Exeter Medical School, said: "Multiple sclerosis can have a devastating impact on people's lives, affecting mobility, speech, mental ability, and more. So far, all medicine can offer is treatment and therapy for the symptoms - as we do not yet know the precise causes, research has been limited. Our exciting new findings have uncovered a new avenue for researchers to explore. It is a critical step, and, in time, we hope it might lead to effective new treatments for MS." Multiple sclerosis affects approximately 2.5 million people around the world. Typically, people are diagnosed in their 20s and 30s, and it is more common in women than men. Although the cause has so far been a mystery, the disease causes the body's own immune system to attack myelin - the fatty "sheaths" that protect nerves in the brain and spinal cord. This leads to brain damage, a reduction in blood supply and oxygen and the formation of lesions in the body.