The intestinal immune system can usually recognize friend from foe. But for approximately 30 million Americans with food allergies—including four million children—immune cells mistakenly identify food as a threat and trigger potentially life-threatening reactions. Now scientists at Washington University School of Medicine in St. Louis have identified essential immune cells in the intestine that prevent unwarranted attacks against harmless food allergens. The study, which was done in mice, further found that in the absence of such cells, mice experienced gut inflammation and an allergic response to food.
Details were published in a recent Cell paper titled, “Rorγt-positive dendritic cells are required for the induction of peripheral Tregs in response to oral antigens.” Commenting on the findings, Marco Colonna, MD, professor of pathology at WashU Medicine, noted that the community is “seeing a rapid global increase in food allergies that significantly impact quality of life. The lack of therapeutics to prevent and manage food allergies complicates the growing public health issue. Now that we know the players that establish tolerance to food allergens, we can devise innovative strategies to target them therapeutically and potentially prevent or treat food allergies.”
Tolerance to food involves multiple immune cells. Certain immune cells pick up food particles, chop them into fragments, and present them to the immune system’s T cells, instructing those cells to remain unresponsive to the harmless intruder. More recently, a small population of cells—the RORγt+ dendritic cells—has been found among the gut’s presenting immune cells in multiple species. Colonna’s lab was one of the first to identify the cells in people in 2023 but their role in preventing food allergies had not been explored.
For the current study, the scientists set out to understand whether RORγt+ dendritic cells are the gut’s immune cells that prevent food allergies. They treated mice with ovalbumin, a highly allergenic protein found in egg whites, orally and then intranasally. Mice lacking gut RORγt+ dendritic cells showed signs of allergic lung inflammation, while mice with these cells did not. Furthermore, an analysis of the gut immune cells found an imbalance among the T cells that trigger versus dampen immune responses to food particles in the allergic mice.
“By removing RORγt+ dendritic cells from the gut in mice, we broke tolerance to food allergens,” said Patrick Rodrigues, PhD, a postdoctoral scholar and co-first author on the study. The findings reported here are motivating additional studies to “see if we can do the opposite: prevent food allergies by supporting the activity of this cell population. Because RORγt+ dendritic cells are found in people, our finding presents an exciting new possibility to manage food allergies and other gut-related immune diseases such as celiac disease or inflammatory bowel disease.”
Furthermore, “targeting the activity of RORγt+ dendritic cells has the potential to work even further upstream to prevent an immune response from first being triggered,” said Shitong Wu, an MD/PhD student and co-first author on the study. “If that proves to be true, a therapy supporting the activity of this small population of cells might offer lasting tolerance to food allergens.”
The post Subset of Intestinal Immune Cells Help Suppress Food Allergies in Mice appeared first on GEN - Genetic Engineering and Biotechnology News.
Details were published in a recent Cell paper titled, “Rorγt-positive dendritic cells are required for the induction of peripheral Tregs in response to oral antigens.” Commenting on the findings, Marco Colonna, MD, professor of pathology at WashU Medicine, noted that the community is “seeing a rapid global increase in food allergies that significantly impact quality of life. The lack of therapeutics to prevent and manage food allergies complicates the growing public health issue. Now that we know the players that establish tolerance to food allergens, we can devise innovative strategies to target them therapeutically and potentially prevent or treat food allergies.”
Tolerance to food involves multiple immune cells. Certain immune cells pick up food particles, chop them into fragments, and present them to the immune system’s T cells, instructing those cells to remain unresponsive to the harmless intruder. More recently, a small population of cells—the RORγt+ dendritic cells—has been found among the gut’s presenting immune cells in multiple species. Colonna’s lab was one of the first to identify the cells in people in 2023 but their role in preventing food allergies had not been explored.
For the current study, the scientists set out to understand whether RORγt+ dendritic cells are the gut’s immune cells that prevent food allergies. They treated mice with ovalbumin, a highly allergenic protein found in egg whites, orally and then intranasally. Mice lacking gut RORγt+ dendritic cells showed signs of allergic lung inflammation, while mice with these cells did not. Furthermore, an analysis of the gut immune cells found an imbalance among the T cells that trigger versus dampen immune responses to food particles in the allergic mice.
“By removing RORγt+ dendritic cells from the gut in mice, we broke tolerance to food allergens,” said Patrick Rodrigues, PhD, a postdoctoral scholar and co-first author on the study. The findings reported here are motivating additional studies to “see if we can do the opposite: prevent food allergies by supporting the activity of this cell population. Because RORγt+ dendritic cells are found in people, our finding presents an exciting new possibility to manage food allergies and other gut-related immune diseases such as celiac disease or inflammatory bowel disease.”
Furthermore, “targeting the activity of RORγt+ dendritic cells has the potential to work even further upstream to prevent an immune response from first being triggered,” said Shitong Wu, an MD/PhD student and co-first author on the study. “If that proves to be true, a therapy supporting the activity of this small population of cells might offer lasting tolerance to food allergens.”
The post Subset of Intestinal Immune Cells Help Suppress Food Allergies in Mice appeared first on GEN - Genetic Engineering and Biotechnology News.