2024-02-07 19:00:28
Updated Wednesday, February 7, 2024 – 20:00
Living with allergies is uncomfortable. If it is food, one learns to be cautious from a young age and avoid those ingredients that can trigger everything from eczema to anaphylactic shock. If it is due to pollens or mites, one becomes disciplined with medication, cleaning and avoids open spaces in spring (especially).
More than 150 million Europeans suffer from some type of allergic disease. Between 23 and 30% of the European population has allergic rhinitis, making it one of the most prevalent chronic diseases. Now 30% of the world’s population suffers from some type of allergy, in 25 years it will be 50%.
3% of the population suffers from food allergies. In Spain this percentage increases the figure four points to 7.4%. In the case of adults, behind half of the reactions are fruits, nuts such as almonds, peanuts or walnuts, and vegetables, such as celery. In children over 5 years of age, an incidence similar to that of adults is observed. On the contrary, in children under 5 years of age the most allergenic foods are eggs, milk and fish.
With these figures and the impact that occurs on the population, solutions are sought to treat and ‘cure’ all types of allergies. But finding the exact key to make the immunological alteration that makes a person allergic or more sensitive to these external stimuli disappear is one of the holy grails of medicine.
Now, two teams of researchers from the Icahn School of Medicine at Mount Sinai have separately described how a population of memory lymphocytes would be the key to maintaining allergies over the years. This advance has seen the light in Science Translational Medicine.
What does ‘allergic memory’ consist of?
Based on studies of children and adults with common allergies, such as peanut allergy, the research data may help answer a long-held puzzle in the field of allergy research by identifying the true source of “allergic memory.” .
The president of the Spanish Society of Allergology and Clinical Immunology (Seaic), Ignacio Jesús Dávila González, explains to EL MUNDO that it is about discovering “how the body maintains IgE levels in the face of an undetermined allergy.” And he adds that “a new mechanism of memory in long-lived cells. Because these cells can live for years, unlike plasma cells that have a short life span. They can have many years of evolution. And maintain the immunology memory of IgE for a long time,” Dávila González puts in context.
Next, the head of the Allergy Service at the University Hospital of Salamanca explains what these two studies mean. “A population of type 2 memory B cells is described, which express IgG, but also the low affinity receptor for IgE, FcRII or CD23, the IL-4 receptor and the IgE heavy chain gene,” points out Dávila González.
Whether or not they will lead to new treatments, Dávila González is cautious. “We can’t give hope without having all the data.” More work is still needed to certify this step. “Yes, we have seen that there are immunotherapy treatments that can modify these IgE cells. But at the moment we are dealing with isolated cases and clinical trials are needed to demonstrate the hypotheses.”
How have they discovered ‘allergic memory’?
In the first study, Miyo Ota and her team at the Icahn School of Medicine at Mount Sinai (USA) describe the discovery of a population of immune cells that support the production of IgE in children with peanut allergy. They examined the immune cells of 58 nut-allergic and 13 non-allergic children, and found that the allergic children had high amounts of a unique type of B cell called type 2 polarized memory B cells.
These B cells expressed highly mutated B cell receptors that recognized the peanut allergen Ara h 2 and could produce IgE, suggesting that these cells explain the long-lasting nature of nut allergies.
Regarding this work, África González Fernández, professor of Immunology at the University of Vigo and researcher at the Biomedical Research Center (CINBIO), points out, as reported by SMC, that “This study confirms in children what had already been previously seen in adults, For example, in two articles of 2016 and of 2020, one with peripheral blood and the other with mucosal cells. Therefore, it is not entirely new, but it does confirm what has been observed by other authors.”
Similarly, Joshua Koenig, from McMaster University (Canada) found that the same population of type 2 polarized memory B cells also maintains allergic memory, based on a study of six adults with birch allergies, four with dust mite allergies, five non-allergic people, and data from adults with peanut allergy.
They also found that these cells generated IgE against specific antigens in some of the patients while they were receiving sublingual immunotherapy for their allergies, demonstrating that these cells act as an important reservoir for the antibody.
“Another therapeutic route [respaldada por estos hallazgos] would be to use allergen immunotherapy in combination with biologics targeting IL-4R or IgE, which could further attenuate type 2 B memory cells and provide long-term benefit,” described the team of Anouk von Borstelfrom Monash University Central Clinical School in the magazine.
#allergies #cured #culprit #cells