Níveis de IgE, IgG2, IgG3 em indivíduos da região Sul do Brasil com rinite alérgica sazonal ao extrato de pólen de Lolium multiflorum

Abstract

Introduction: Lolium multiflorum (Lm), a grass species belonging to the Poaceae family, is recognized as the primary cause of hay fever in the Southern region of Brazil. Understanding the role of IgG subclasses in the allergic response is crucial, as these antibodies play distinct functions in the immune system. However, up to this point, the mechanisms of IgG2 and IgG3 subclasses in allergy remain poorly understood. Objectives: To evaluate the humoral immune response profile of IgE, IgG2, and IgG3 in atopic patients to L. multiflorum diagnosed with hay fever. Materials and Methods: Serum samples were collected from 27 individuals, who were divided into atopic (AT) and non-atopic (NAT) groups through the skin prick test (SPT). Reactivity to specific anti-Lm antibodies of IgE, IgG2, and IgG3 classes was assessed through immunoenzymatic assays. Results: A significant difference was observed in the increased levels of specific IgE among AT individuals compared to NAT. However, no significant differences were observed in the levels of IgG2 and IgG3 in both groups. There was a positive correlation between the SPT and IgE levels in both groups (AT and NAT), as the size of the wheal correlated with specific IgE levels to L. multiflorum, unlike what was observed for IgG2 and IgG3, where there was no correlation between SPT and IgG2 and IgG3 levels. IgE levels against Lm were correlated with IgG3; however, the same was not observed for IgG2. Conclusions: The obtained results provide significant information about the immune responses triggered by allergens present in L. multiflorum pollen, contributing to a better understanding of the immunological profile that triggers symptoms associated with seasonal allergic rhinitis.