lymphatic system
Snapshots of Life: The Brain’s Microscopic Green Trash Bins
Posted on by Dr. Francis Collins
Credit: Marina Venero Galanternik, Daniel Castranova, Tuyet Nguyen, and Brant M. Weinstein, NICHD, NIH
There are trash bins in our homes, on our streets, and even as a popular icon on our desktop computers. And as this colorful image shows, trash bins of the cellular variety are also important in the brain.
This image—a winner in the Federation of American Societies for Experimental Biology’s 2017 BioArt competition—shows the brain of an adult zebrafish, a popular organism for studying how the brain works. It captures dense networks of blood vessels (red) lining the outer surface of the brain. Next to many of these vessels sit previously little-studied cells called fluorescent granular perithelial cells (yellowish green). Researchers now believe these cells, often shortened to FGPs, act much like trash receptacles that continuously take in and store waste products to keep the brain tidy and functioning well.
New Imaging Approach Reveals Lymph System in Brain
Posted on by Dr. Francis Collins
Considering all the recent advances in mapping the complex circuitry of the human brain, you’d think we’d know all there is to know about the brain’s basic anatomy. That’s what makes the finding that I’m about to share with you so remarkable. Contrary to what I learned in medical school, the body’s lymphatic system extends to the brain—a discovery that could revolutionize our understanding of many brain disorders, from Alzheimer’s disease to multiple sclerosis (MS).
Researchers from the National Institute of Neurological Disorders and Stroke (NINDS), the National Cancer Institute (NCI), and the University of Virginia, Charlottesville made this discovery by using a special MRI technique to scan the brains of healthy human volunteers [1]. As you see in this 3D video created from scans of a 47-year-old woman, the brain—just like the neck, chest, limbs, and other parts of the body—possesses a network of lymphatic vessels (green) that serves as a highway to circulate key immune cells and return metabolic waste products to the bloodstream.
Creative Minds: New Piece in the Crohn’s Disease Puzzle?
Posted on by Dr. Francis Collins
Gwendalyn Randolph
Back in the early 1930s, Burrill Crohn, a gastroenterologist in New York, decided to examine intestinal tissue biopsies from some of his patients who were suffering from severe bowel problems. It turns out that 14 showed signs of severe inflammation and structural damage in the lower part of the small intestine. As Crohn later wrote a medical colleague, “I have discovered, I believe, a new intestinal disease …” [1]
More than eight decades later, the precise cause of this disorder, which is now called Crohn’s disease, remains a mystery. Researchers have uncovered numerous genes, microbes, immunologic abnormalities, and other factors that likely contribute to the condition, estimated to affect hundreds of thousands of Americans and many more worldwide [2]. But none of these discoveries alone appears sufficient to trigger the uncontrolled inflammation and pathology of Crohn’s disease.
Other critical pieces of the Crohn’s puzzle remain to be found, and Gwendalyn Randolph thinks she might have her eyes on one of them. Randolph, an immunologist at Washington University, St. Louis, suspects that Crohn’s disease and other related conditions, collectively called inflammatory bowel disease (IBD), stems from changes in vessels that carry nutrients, immune cells, and possibly microbial components away from the intestinal wall. To pursue this promising lead, Rudolph has received a 2015 NIH Director’s Pioneer Award.
Happy New Year … and a Look Back at a Memorable 2015
Posted on by Dr. Francis Collins
A new year has arrived, and it’s going to be an amazing one for biomedical research. But before diving into our first “new science” post of 2016, let’s take a quick look back at 2015 and some of its remarkable accomplishments. A great place to reflect on “the year that was” is the journal Science’s annual Top 10 list of advances in all of scientific research worldwide. Four of 2015’s Top 10 featured developments directly benefited from NIH support—including Science’s “Breakthrough of the Year,” the CRISPR/Cas9 gene-editing technique. Here’s a little more on the NIH-assisted breakthroughs:
CRISPR Makes the Cut: I’ve highlighted CRISPR/Cas9 in several posts. This gene-editing system consists of a short segment of RNA that is attached to an enzyme. The RNA is preprogrammed to find a distinct short sequence of DNA and deliver the enzyme, which acts like a scalpel to slice the sequence out of the genome. It’s fast and pretty precise. Although CRISPR/Cas9 isn’t brand-new—it’s been under development as a gene-editing tool for a few years—Science considered 2015 to be “the year that it broke away from the pack.”
