INVESTIGADORES
MUGLIA Cecilia Isabel
congresos y reuniones científicas
Título:
Food Allergy: Lessons from Juvenile Polyps
Autor/es:
MUGLIA C.I.
Lugar:
Mar del Plata
Reunión:
Congreso; Reunión Conjunta SAIC SAI FACIC SAFIS 2022; 2022
Institución organizadora:
Sociedad Argentina de Inmunología
Resumen:
Food allergies, including cow´s milk protein allergy (CMA), are adverse immune response to food proteins, which are growing worldwide, affecting 5-10% of children and 1-3% of adults. These disorders can be classified as IgE-, non-IgE- and mixed allergic reactions. IgE mediated allergies are of concern because of the risk of severe reactions such as anaphylaxis. Evidence regarding the mechanisms of IgE production in the human gut are scarce, and little is known about IgE memory cells.We have been working for several years on colorectal juvenile polyps (JP) from children sensitized to cow´s milk proteins (CMP). These polyps, which promote rectal bleeding, are routinely removed by colonoscopy, and constitute an excellent human tissue to study the mucosal underlying mechanisms that provoke food allergies. We reported a prominent cellular infiltrate in JP rich in mononuclear cells, eosinophils, and mast cells. We demonstrated the presence of active germinal centers, with a high frequency of CD20+ cells (B cells), ki67+ cells (proliferating cells) and AID+ cells (cells undergoing class switch recombination and hypermutation). The stroma also showed to contain IgE+ plasma cells (IgE+CD138+ cells). All these features refer as active and Ig-producing germinal centers in the stroma of polyps, and we demonstrated for the first time that the human colon is a mucosal site for production of IgE. Furthermore, we described in the polyp stroma a Th2 inflammatory environment, with high levels of IL-4 and a high IL-13/IFN-γ ratio compared to the surrounding tissue, and the presence of milk-specific T cells expressing gut homing integrins. Finally, JP are rich in pro-inflammatory and type-2 chemokines secreted by epithelial cells, which may play a central role in the promotion of the local allergic response and development of polyps.In conclusion, our findings reveal the role of epithelial cells in the inflammatory environment and IgE synthesis found in JP and indicate a potential link between JP and food allergy.