Study: A Newly Identified Immune Cell Drives Anaphylaxis in Mice
In a FARE-funded study published in the prestigious journal Science, researchers at Yale University and other institutions report the discovery of a subset of immune cells that is important in anaphylaxis, a severe and potentially life-threatening allergic reaction. The study team was led by Dr. Stephanie Eisenbarth, who received a FARE Investigator in Food Allergy award in 2017 and is the Ira & Diana Riklis Family Research Award in Food Allergy Recipient.
Anaphylaxis can be triggered when a defense protein in the blood, an antibody called IgE, binds to a normally harmless foreign protein (an allergen), setting off a storm of immune responses that overwhelms the body. Immune system cells called T cells control the production of antibodies, including IgE. In a summary of their study, the researchers describe T cells as generals in the immune system, directing the behavior of other defense cells. There are many types of antibodies and many types of T cells. Prior to the study, scientists did not know which type of T cell promotes the production of IgE antibodies that bind tightly to allergens and can cause anaphylaxis.
The research team has been studying a genetic form of food allergy that is quite rare in people but can be reproduced and studied in mice. Investigators compared genetically normal mice with mice engineered to lack a protein called DOCK8 in their T cells. In the process, they found a new type of T cell that they named Tfh13, or T follicular helper cell producing IL-13. Interleukin 13, a chemical signal released by some T cells associated with allergy, contributes to the allergic immune response, but was not previously considered key for anaphylaxis.
In mice, Tfh13 cells influence other cells that drive production of the IgE antibodies that can trigger anaphylaxis. When mice lost the ability to make Tfh13 cells, they also lost the ability to make anaphylaxis-inducing IgE antibodies. Researchers also found that Tfh13 cells circulate in the blood of patients with food allergies and asthma, so these cells could play a role in human allergies as well.
The identification of Tfh13 cells holds the potential for exciting future prospects. These include improved methods for assessing anaphylaxis risk in allergic patients, as well as new therapies to interfere with the production of IgE antibodies associated with anaphylaxis. We congratulate the researchers on their discovery and thank everyone whose donations to FARE have helped make this work possible.
Learn more about Dr. Eisenbarth’s research in this previously published interview.