TLR4 receptor and selected cytokines in development of food allergy in infants and small children

Abstract

Introduction: Food allergy (FA) in infants and small children is an important and rising problem. TLR4 is the main receptor recognizing lipopolysaccharide (LPS) and belonging to the Tolllike receptor (TLR) family. Triggering this receptor leads to activation of nuclear factor κB (NF-κB) and interferon regulatory factors (IRFs) and expression of genes included in immunological reactions. Material and methods: Fifty children (aged 1-36 months) were included in this study: 35 children with food allergy (17 of them with IgE-dependent allergy, 18 with IgE-independent allergy) and 15 healthy children without any allergy. In this work mRNA expression of TLR4 receptor on neutrophils and concentrations of selected Th1/Th2 cytokines were evaluated. Results: We observed lower mRNA TLR4 expression in children with food allergy especially IgE-independent food allergy. Furthermore, higher concentrations of IL-4, IL-5 and IL-10 in children with food allergy compared with children from the control group were found. Estimated mRNA expression of TLR4 on neutrophil surfaces was negatively correlated with serum concentration of IL-4 and positively correlated with IFN-γ serum levels in children with IgE-dependent FA. Conclusions: Results of this study suggest a role of innate immunity in the development of food allergy and evaluation of this immunity can be helpful in diagnosis of allergy in small children.