immune
Imaging Advance Offers New View on Allergic Asthma
Posted on by Dr. Francis Collins
Caption: OR-OCT images of the airways of a healthy person (left) and a person with allergic asthma (right). The colorized portion highlights airway smooth muscle, with thinner areas in purple and black and thicker areas in yellow and orange. Credit: Cho et al., Science Translational Medicine (2016)
You probably know people who sneeze a little when they encounter plant pollens, pet dander, or other everyday allergens. For others, however, these same allergens can trigger a serious asthma attack that can make breathing a life-or-death struggle. Now, two NIH-funded research groups have teamed up to help explain the differences in severity underlying the two types of reactions.
In the studies, researchers at Massachusetts General Hospital, Boston, used an innovative imaging tool to zoom in on a person’s airways safely in real time to gain an unprecedented view of how his or her body reacts to allergens [1,2]. The imaging revealed key differences between the asthma and non-asthma groups in the smooth muscle tissue that surrounds critical airways, and is responsible for constriction. In a complementary series of experiments, researchers also uncovered heightened immune responses in the airways of folks with allergic asthma. The findings offer important new clues in the quest to better understand and guide treatment for asthma, a condition that affects more than 300 million people around the world.
The factors driving airway constriction in people with asthma have been poorly understood in part because, until now, there hasn’t been a way to view airway smooth muscle in action. As described in the journal Science Translational Medicine, Melissa Suter and colleagues adapted an established form of imaging called optical coherence tomography (OCT) to help fill this gap. Standard OCT produces an image by measuring the amount of light reflected back from body tissues, but such images aren’t sufficient to distinguish airway smooth muscle from other tissues.
Snapshots of Life: NIH’s BioArt Winners
Posted on by Dr. Francis Collins
Credit: FASEB
If you follow my blog, you know that I like to feature spectacular images that scientists have created during the course of their research. These images are rarely viewed outside the lab, but some are so worthy of artistic merit and brimming with educational value that they deserve a wider audience. That’s one reason why the Federation of American Societies for Experimental Biology (FASEB) launched its BioArt contest. Of the 12 winners in 2013, I’m proud to report that 11 received support from NIH. In fact, I’m so proud that I plan to showcase their work in an occasional series entitled “Snapshots of Life.” Continue reading to see the first installment—enjoy!
‘No Ouch’ Vaccine Patch
Posted on by Dr. Francis Collins
A vaccine patch and a view of the “needles” using scanning electron microscopy.
Credit: Peter DeMuth/Wellcome Trust
This might be a new way to get a shot. Funded in part by the NIH, this vaccine patch [1] is coated in a thin film that literally melts into the skin when the patch is applied. The film contains DNA, rather than protein, which is absorbed by the skin cells and triggers an immune reaction. It seems to be effective in animal models. DNA vaccines are attractive because they may not require refrigeration like typical protein vaccines and can be stably stored for weeks. And, though this patch looks spiky, the length of the needles can be adjusted so that they don’t reach the skin layers that contain nerves. Thus: no ouch.
[1] Polymer multilayer tattooing for enhanced DNA vaccination. Demuth PC, Min Y, Huang B, Kramer JA, Miller AD, Barouch DH, Hammond PT, Irvine DJ. Nat Mater. 2013 Jan 27.
NIH support: the National Institute of Allergy and Infectious Diseases
Taking a Snapshot of the Human Immune System
Posted on by Dr. Francis Collins
Source: National Cancer Institute Visuals Online, NIH
There are numerous tests to gauge the health of your heart. But no such widely accepted test exists for the many parts of the immune system. How can we tell if the immune system is strong or weak? Or quantify how badly it’s malfunctioning when we suffer from asthma, allergies, or arthritis?
A team led by scientists at Stanford University has taken the first steps toward creating such a test—by taking “snapshots” of the immune system.
Before we talk about what they did, let me review how the immune system protects us against disease. The innate immune system is like a standing army that defends us against invading microbes. But the innate system has no memory. It doesn’t recognize the invaders more quickly if they return. This is the job of the adaptive immune system—B and T cells. These cells not only remember invaders; they’re able to adapt their weapons—antibodies and T-cell receptors—to make them more effective. Think of them as the Special Forces.
Who Knew? Gut Bacteria Contribute to Malnutrition
Posted on by Dr. Francis Collins
A child suffering from kwashiorkor.
Source: CDC/Phil
Here’s a surprising result from a new NIH-funded study: a poor diet isn’t the only cause of severe malnutrition. It seems that a ‘bad’ assortment of microbes in the intestine can conspire with a nutrient poor diet to promote and perpetuate malnutrition [1].
Most of us don’t spend time thinking about it, but healthy humans harbor about 100 trillion bacteria in our intestines and trillions more in our nose, mouth, skin, and urogenital tracts. And though your initial reaction might be “yuck,” the presence of these microbes is generally a good thing. We’ve evolved with this bacterial community because they provide services—from food digestion to bolstering the immune response—and we give them food and shelter. We call these bacterial sidekicks our ‘microbiome,’ and the latest research, much of it NIH-funded, reveals that these life passengers are critical for good health. You read that right—we need bacteria. The trouble starts when the wrong ones take up residence in our body, or the bacterial demographics shift. Then diseases from eczema and obesity to asthma and heart disease may result. Indeed, we’ve learned that microbes even modulate our sex hormones and influence the risk of autoimmune diseases like type 1 diabetes. [2]
