Test Tube Tuesday

Taming Immune Cells with a Molecular “Switch”

T cell

The most important step to solving any problem is to choose the right tool for the job. Just like a heavy fur coat will keep you comfortable in the Arctic but slowly roast you in the Sahara, your immune system’s response can be helpful or harmful depending on the specific invader it’s fighting off. A new IRP study has identified a molecular “switch” that shifts an important type of immune cell between two different approaches to protecting the body.

Urban Upbringing Flips Genes’ Effects on Brain Activity

taxi cabs in a city street

It might seem easy to blame your parents for the way you turned out; after all, they raised you and gave you all of your DNA. But, before throwing blame around, consider saving some for the place where you grew up. According to new IRP research, being raised in an urban environment can dramatically alter how your genes influence your brain.1

Which Neurons Are Responsible for Anxiety-Related Behaviors?

anxious man afraid to enter into a group conversation

Most people experience anxiety at some point in their lives, whether it’s pre-speech jitters or sweaty palms when their plane takes off. While mild feelings of nervousness are completely normal and can even be beneficial, anxiety can also have negative repercussions if it causes somebody to completely avoid situations like social encounters or taking a flight to visit distant family.

In Utero Exposure to Immune Molecules May Affect Neurocognitive Development

young child at school

In the midst of the 1957 Asian flu pandemic, doctors and researchers were understandably focused on treating patients and developing ways to contain the outbreak. It wasn’t until 30 years later that scientists began reporting that women who were pregnant when they caught the virus were more likely to have children who would later be diagnosed with schizophrenia.1 While that relationship remains controversial,2 numerous studies have since linked activation of a pregnant woman’s immune system with an increased risk that her child will develop certain psychiatric disorders, including not just schizophrenia but also autism spectrum disorder and major depressive disorder.3 A new IRP study has now expanded on this work by showing that exposure to higher levels of two immune system molecules in utero can noticeably alter the neurological and cognitive development of young children.4

IRP Scientists Curb Inflammation to Protect Brain Cells From Stroke

schematic of an ischemic stroke

Every forty seconds, someone in the United States suffers a stroke, and researchers across the country are hunting for a way to help brain cells survive these traumatic events. A group of IRP researchers recently discovered a promising new tool to aid in this effort. By blocking the action of a brain chemical called monoacylglycerol lipase (MAGL), the scientists markedly reduced stroke-related brain damage and disability in rats.1

Sleep Apnea Produces Troubling Signs of Future Brain Disease

sleeping elderly couple

Like a bear leaves its ominous footprints in the snow, diseases and other biological processes often leave traces throughout our bodies. Recent technological and scientific advances have enabled clinicians to use measurements of these ‘biomarkers’ in their attempts to improve our health. A new study by IRP researchers revealed that patients with a sleep disorder called obstructive sleep apnea (OSA) have higher blood concentrations of certain biomarkers that may foreshadow poor brain health later in life.1

When people with OSA sleep, their throat muscles relax and block their windpipes, preventing proper breathing and often waking them up. As a result, these individuals get lower-quality sleep and their brains receive less oxygen at night.

“The overall idea is that those two conditions are not good for brain health, but nobody had really looked to see if some of the biomarkers we see in brain injury are also common in younger individuals with this type of disordered breathing,” says IRP Lasker Clinical Research Scholar Jessica Gill, Ph.D., R.N., the study’s senior author.

Intermittent Fasting Boosts Endurance in Mouse Marathoners

runner tying his shoe

Food companies have long marketed carbohydrate-rich drinks and energy bars to athletes with the message that the energy those snacks provide is key to lifting heavier and running farther. A new mouse study by IRP researchers, however, suggests that skipping a meal (or several) might be far more effective for increasing athletic prowess1.

Unlike modern Americans used to three square meals a day, our ancient ancestors couldn’t exactly throw a TV dinner in the microwave whenever they felt a bit peckish. As a result, they probably found themselves hunting wooly mammoths and fending off saber-toothed tigers on an empty stomach.

“From an evolutionary perspective, animals in the wild – particularly predators – need to be able to function at a high level when they’re in a food-deprived state,” says IRP Senior Investigator Mark P. Mattson, Ph.D., the study’s senior author. “Individuals who were able to perform at a high level in a fasted state had a survival advantage.”

HIV Uses Host's Own Immune Molecules for Protection

an HIV-infected T cell

In one of Aesop’s classic fables, a clever wolf dons a sheep’s skin in order to move through the herd undetected. As it turns out, IRP researchers have discovered that in people with a specific set of immune system genes, the HIV virus uses a similar approach to hide from the body’s defenses.1

Nearly all cells in our bodies are coated with proteins called human leukocyte antigens (HLAs). These proteins allow the immune system to distinguish between healthy, native cells and those contaminated by unwelcome visitors like viruses or bacteria that must be destroyed. Each of the various HLA proteins is encoded by a different HLA gene and these genes vary considerably between individuals, causing different people to have different variants of each HLA protein.

“There are thousands of different forms of these HLA genes, and that variation allows us, as a species, to deal with virtually all infectious pathogens,” says IRP Senior Investigator Mary N. Carrington, Ph.D., the senior author of the new paper. “We’re really interested in the diversity of that part of the genome, since the risk of essentially every autoimmune disease, many cancers, and probably every infectious disease is associated with this set of genes.”

Gut Bugs May Convert High-Fat Fare into Cancer Risk

cartoon image of the gut microbiome showing microbes in the digestive tract

Researchers have a long history of fattening up mice to gain insight into the causes and consequences of weight gain in the human body. In one of the more recent studies of this kind, a team of IRP researchers found that that a high-fat diet consistently altered the collection of microbes residing in mice’s digestive tracts and that this diet-microbe combination might pre-dispose the mice – and, potentially, obese humans – to colon cancer by triggering certain changes in how genes behave.