antibody
Antibody Makes Alzheimer’s Protein Detectable in Blood
Posted on by Dr. Francis Collins
Caption: The protein tau (green) aggregates abnormally in a brain cell (blue). Tau spills out of the cell and enters the bloodstream (red). Research shows that antibodies (blue) can capture tau in the blood that reflect its levels in the brain.
Credit: Sara Moser
Age can bring moments of forgetfulness. It can also bring concern that the forgetfulness might be a sign of early Alzheimer’s disease. For those who decide to have it checked out, doctors are likely to administer brief memory exams to assess the situation, and medical tests to search for causes of memory loss. Brain imaging and spinal taps can also help to look for signs of the disease. But an absolutely definitive diagnosis of Alzheimer’s disease is only possible today by examining a person’s brain postmortem. A need exists for a simple, less-invasive test to diagnose Alzheimer’s disease and similar neurodegenerative conditions in living people, perhaps even before memory loss becomes obvious.
One answer may lie in a protein called tau, which accumulates in abnormal tangles in the brains of people with Alzheimer’s disease and other “tauopathy” disorders. In recent years, researchers have been busy designing an antibody to target tau in hopes that this immunotherapy approach might slow or even reverse Alzheimer’s devastating symptoms, with promising early results in mice [1, 2]. Now, an NIH-funded research team that developed one such antibody have found it might also open the door to a simple blood test [3].
Rare Disease Mystery: Nodding Syndrome May Be Linked to Parasitic Worm
Posted on by Dr. Francis Collins
Caption: Village in the East Africa nation of Uganda
Credit: Centers for Disease Control and Prevention
In the early 1960s, reports began to surface that some children living in remote villages in East Africa were suffering mysterious episodes of “head nodding.” The condition, now named nodding syndrome, is recognized as a rare and devastating form of epilepsy. There were hints that the syndrome might be caused by a parasitic worm called Onchocerca volvulus, which is transmitted through the bites of blackflies. But no one had been able to tie the parasitic infection directly to the nodding heads.
Now, NIH researchers and their international colleagues think they’ve found the missing link. The human immune system turns out to be a central player. After analyzing blood and cerebrospinal fluid of kids with nodding syndrome, they detected a particular antibody at unusually high levels [1]. Further studies suggest the immune system ramps up production of that antibody to fight off the parasite. The trouble is those antibodies also react against a protein in healthy brain tissue, apparently leading to progressive cognitive dysfunction, neurological deterioration, head nodding, and potentially life-threatening seizures.
The findings, published in Science Translational Medicine, have important implications for the treatment and prevention of not only nodding syndrome, but perhaps other autoimmune-related forms of epilepsy. As people in the United States and around the globe today observe the 10th anniversary of international Rare Disease Day, this work provides yet another example of how rare disease research can shed light on more common diseases and fundamental aspects of human biology.
Nanoparticles Target Damaged Blood Vessels
Posted on by Dr. Francis Collins
Caption: [A] Elastin stain (black) showing damaged elastic lamina in aorta. Inset (higher magnification) shows fluorescent nanoparticles attached to aorta where elastin is damaged. [B] Elastin stain showing aorta with undamaged elastic lamina. Inset shows no nanoparticle attachment. L stands for lumen, the open area inside the aorta.
Credit: Naren Vyavahare, Clemson University
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.
Previous Page
