Answers to submitted questions will be answered and updated hopefully on a weekly basis. I will try my hardest to answer in a timely manner. Some responses may answer multiple questions that I grouped together. Check out what other people have asked first! Your burning question might have already been answered! ---Bryan
1. What made you decide to study the brain and immunology? (Allison, Texas & Diane, Indiana)
Studying patterns in biology is something I’ve been interested in since my first biology class in high school, though I didn’t know what I would actually find interesting enough to do a PhD in until almost a decade later! The brain is amazing, but also really difficult to study in humans. Many of the things that go wrong might be related to problems in the immune system, another system I love. It seemed natural to combine the two and study how the immune system hurts and helps the brain survive!
2. How does being a biologist at Stanford work? (Allison, Texas & Diane, Indiana)
I studied neuroscience in undergrad, and worked in labs at NASA for a few years before deciding I wanted to study immunology in a PhD program. Stanford has a wonderful community of scientists in many sciences, and the best part is getting to work with people from different fields to solve really difficult problems. Everyone’s path through science is different. The best advice is to find things that interest you, and pursue labs or jobs that match. The people there will support you as you continue to work and figure out what you want to do next!
3. Could the plaques/tangles in the brain be caused by the brain trying to protect itself or trying to repair its own damage? (Allison, Texas)
Maybe! We don’t really know why the plaques and tangles form, and why only certain proteins end up in these shapes. There are many people who are studying how and why these proteins fold incorrectly - hopefully telling us more about why these proteins seems to be ‘bad’.We aren’t exactly sure if the immune system is helping or hurting the brain in Alzheimer’s Disease. This is a big part of what I’m hoping to figure out - like you suggest, maybe they’re trying to help but end up causing problems. By digging down into the specific features of microglia, we can hopefully identify the tools these cells use in human brains and then test whether they help or hurt brain cells in future experiments. The results might tell us how specific types of microglia are hurting or preventing Alzheimer’s Disease.
5. Who gets Alzheimer's Disease? Do we know why? (Allison, Texas)
We don’t currently understand how Alzheimer’s Disease occurs, though it tends to only happen in older people (65 years old and older). Rarely it can show up in younger people, and as you guessed it’s probably due to a genetic issue in these people - this type of the disease shows up only in certain families. Genes that are associated with increased risk are ApoE, PSEN, and TREM2, though again, we’re not entirely sure why!
4. How do microglia move through the brain? Wouldn't they bump into the neurons in the brain? (Allison, Texas)
They do bump into neurons! They also travel around them, over them, and under neurons and the other cells in the brain. They use special signals called chemoattractants to tell them where to move to next. Here’s a short video showing what this looks like.
6. Why does the brain shrink as we age? (Allison, Texas)
We’re not entirely sure why the brain shrinks as we age, though we think the reasons for shrinking are different in aged people compared to people with Alzheimer’s Disease. It’s possible our neurons (primary brain cells) are dying or shrinking for some reason as we grow older.
7. What's the effect of stress and cortisol on the brain in Alzheimer's Disease? (Galia, California)
Prolonged stress is definitely not great for the brain, or any part of the body for that matter. We know there’s an association between increased cortisol and increased likelihood of Alzheimer’s Disease, but once again we’re not sure why. Stress can actually inhibit the immune system in the rest of your body, so it’s possible this is one avenue researchers should look into to see how hormones control the immune response in the brain.You need cortisol for many other bodily functions, so you wouldn’t want to stop it. You might instead figure out where it’s acting in the brain and design a drug or device to prevent that specific problem though!
8. Why do older people get Alzheimer's? Is this disease caused by the proteins that build up in the brain or is it just a mere product? (Mia, )
Older people definitely tend to accumulate the plaques and tangles of the disease-associated proteins more than those who are younger. However not everyone with a large amount of protein buildup will develop Alzheimer's, and some people will develop the disease even without a large buildup. This inconsistencey is one of the aspects of the disease we think might be due to differences in the human brain immune system between elderly people and how it reacts to these proteins and other issues like infections.
9. Can a mental illness like ADHD affect the growth or the development of the brain?
(Elias, New Mexico)
Mental health concerns like ADHD, Bipolar Disorder, Depression, and others can have an effect on the development of the brain, though these are areas of neuroscience that are really not understood well - even less so than diseases like Alzheimer's. Luckily with the help of psychiatrists, therapists, and other factors, people who develop with these issues can still lead full, normal lives. Even if we don't understand how it works, the brain is incredibly resilient and responsive.