You Won’t Believe What’s In These Pills

Fecal pills

Credit:: Hohmann lab

Clostridium difficile, or more commonly “C. diff,” is a nasty bacterium that claims the lives of 14,000 Americans every year. Most at risk are people with conditions requiring prolonged use of antibiotics, which have the unfortunate side effect of wiping out the natural, good bacteria in the colon—thus allowing bad bugs like C. diff to multiply unchecked. In many folks, C. diff infection can be treated by halting the original antibiotics and switching to other types of antibiotics. But for some people, that doesn’t work—C. diff is either resistant to treatment or makes a hasty comeback.

What’s to be done then? Well, researchers have known for some time that taking microbe-rich stool samples from healthy people and transplanting them into C. diff patients helps to improve their symptoms. The challenge has been figuring out a safe and effective way to do this that is acceptable to patients and doesn’t involve invasive procedures, such as colonoscopy or nasogastric tubes [1,2]. Could there be a simple solution? To put it more bluntly: what about poop pills?

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Stem Cell Science: Taking Aim at Type 1 Diabetes

human stem cell-derived beta cells

Caption: Insulin-producing pancreatic beta cells (green) derived from human embryonic stem cells that have formed islet-like clusters in a mouse. The red cells are producing another metabolic hormone, glucagon, that regulates blood glucose levels. Blue indicates cell nuclei.
Credit: Photo by B. D. Colen/Harvard Staff; Image courtesy of Doug Melton

For most of the estimated 1 to 3 million Americans living with type 1 diabetes, every day brings multiple fingerpricks to manage their blood glucose levels with replacement insulin [1,2]. The reason is that their own immune systems have somehow engaged in friendly fire on small, but vital, clusters of cells in the pancreas known as the islets—which harbor the so-called “beta cells” that make insulin. So, it’s no surprise that researchers seeking ways to help people with type 1 diabetes have spent decades trying a find a reliable way to replace these islets.

Islet replacement has proven to be an extremely difficult research challenge for a variety of reasons, but exciting opportunities are now on the horizon. Notably, a team of researchers, led by Douglas Melton of Harvard University, Cambridge, MA, and partially funded by NIH, reported groundbreaking success just last week in spurring a human embryonic stem cell (hESC) line and two human-induced pluripotent stem (iPS) cell lines to differentiate into the crucial, insulin-producing beta cells. Not only did cells generated from all three of these lines look like human pancreatic beta cells, they functioned like bona fide, glucose-responsive beta cells in a mouse model of type 1 diabetes [3].

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NIH Ebola Update: Working Toward Treatments and Vaccines

Ebola virus and development of therapeutics

Credit: National Institutes of Health

Updated Oct. 22, 2014: The National Institutes of Health (NIH) today announced the start of human clinical trials of a second Ebola vaccine candidate at the NIH Clinical Center in Bethesda, MD. In this early phase trial, researchers from NIH’s National Institute of Allergy and Infectious Diseases (NIAID) are evaluating the vaccine, called VSV-ZEBOV, for its safety and ability to generate an immune response in healthy adults who receive two intramuscular doses, called a prime-boost strategy.

The Walter Reed Army Institute of Research is simultaneously testing the vaccine candidate as a single dose at its Clinical Trials Center in Silver Spring, MD. VSV-ZEBOV, which was developed by researchers at the Public Health Agency of Canada’s National Microbiology Laboratory, has been licensed to NewLink Genetics Corp. through its wholly owned subsidiary BioProtection Systems, both based in Ames, Iowa.

Early human testing of another Ebola vaccine candidate, co-developed by NIAID and GlaxoSmithKline, began in early September at the NIH Clinical Center. Initial data on that vaccine’s safety and ability to generate an immune response are expected by the end of 2014.

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We are all alarmed by the scope and scale of the human tragedy occurring in West African nations affected by the Ebola virus disease epidemic. While the cornerstones of the Ebola response remain prompt diagnosis and isolation of patients, tracing of contacts, and proper protective equipment for healthcare workers, the National Institutes of Health (NIH), led by its National Institute of Allergy and Infectious Diseases (NIAID), is spearheading efforts to develop treatments and a vaccine for Ebola as quickly as possible.

For example, NIAID has supported and collaborated with Mapp Biopharmaceutical, Inc., San Diego, in its development of the product known as ZMapp, which has been administered experimentally to several Ebola-infected patients. While it is not possible at this time to determine whether ZMapp benefited these patients, NIAID is supporting a broader effort to advance development and clinical testing of ZMapp to determine if it is safe and effective. In addition, the U.S. Biodefense Advanced Research and Development Agency (BARDA) has announced plans to optimize and accelerate the manufacturing of ZMapp, which is in limited supply, to enable clinical safety testing to proceed as soon as possible.

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Snapshots of Life: Allergen Art

Pollen grains

Credit: Edna, Gil, and Amit Cukierman, Fox Chase Cancer Center, Philadelphia

Seasonal allergy sufferers, allow me to take advantage of the powers of confocal microscopy to introduce you to your tormenter: pollen. Although pollen grains look amazing at this magnification, their effects on many of us are not so wonderful. These spiky spheres can trigger an immune reaction that produces the runny nose, itchy eyes, and other symptoms that make people with pollen allergies miserable from early spring through late fall.

In fact, this image was created by a seasonal allergy sufferer who also happens to be a cell biologist. On a Saturday afternoon about a decade ago, Edna Cukierman of Philadelphia’s Fox Chase Cancer Center had just received a new spinning disc confocal microscope and couldn’t wait to try it out. There was just one catch—she also had to watch her two children. Not to be deterred, this multi-tasking scientist/mom turned the process of calibrating her new microscope into a creative way of entertaining her kids.

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Taking a New Look at Artificial Sweeteners

Packets of artificial sweetenersDiet sodas and other treats sweetened with artificial sweeteners are often viewed as guilt-free pleasures. Because such foods are usually lower in calories than those containing natural sugars, many have considered them a good option for people who are trying to lose weight or keep their blood glucose levels in check. But some surprising new research suggests that artificial sweeteners might actually do the opposite, by changing the microbes living in our intestines [1].

To explore the impact of various kinds of sweeteners on the zillions of microbes living in the human intestine (referred to as the gut microbiome), an Israeli research team first turned to mice. One group of mice was given water that contained one of two natural sugars: glucose or sucrose; the other group received water that contained one of three artificial sweeteners: saccharin (the main ingredient in Sweet’N Low®), sucralose (Splenda®), or aspartame (Equal®, Nutrasweet®). Both groups ate a diet of normal mouse chow.

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