Ashlyn Poole1,2, Yong Song1,2, Michael O'Sullivan3, Khui Hung Lee1,2, Jessica Metcalfe3, Jing Guo1,2, Helen Brown1, Ben Mullins1, Richard Loh3, Guicheng Brad Zhang1,2,4. 1. School of Public Health, Curtin University, Bentley, WA, Australia. 2. Centre for Genetic Origins of Health and Disease, The University of Western Australia, Crawley, WA, Australia. 3. Department of Immunology, Princess Margaret Hospital for Children, Subiaco, WA, Australia. 4. Curtin Health Innovation Research Institute, Curtin University, Bentley, WA, Australia.
Abstract
BACKGROUND: Trends in food allergies prompted investigation into the underlying mechanisms. Genetic and epigenetic factors are of high interest, and, in particular, the interplay between genes relating to immune factors directly and indirectly involved in food allergy pathogenesis. We sought to determine potential links between gene expression and epigenetic factors relating to Toll-like receptor (TLR) pathways and childhood food allergies. METHODS: In a cross-sectional study, samples from 80 children with and without food allergies were analysed for gene expression, DNA methylation and a range of immune factors relating to TLR pathways. TLR2, TLR4, CD14, IL5, IL13 and vitamin D were explored. RESULTS: The importance of these immune factors appeared to vary between the different types of food allergies. Expression of TLR2 (P < .001), TLR4 (P = .014) and CD14 (P = .028) varied significantly between children with no food allergy, allergy to nuts and peanuts, and allergy to eggs. DNA methylation in the promoter regions of these genes had a significant association with gene expression. These trends persisted when subjects were stratified by nut allergy vs no nut allergy. Furthermore, TLR2 (P = .001) and CD14 (P = .007) expressions were significantly lower in children with food allergies when compared to those without. CONCLUSION: Gene expression of TLR pathway genes was directly related to food allergy type, and DNA methylation had an indirect effect. TLR2 pathways are of significant interest in nut allergies.
BACKGROUND: Trends in food allergies prompted investigation into the underlying mechanisms. Genetic and epigenetic factors are of high interest, and, in particular, the interplay between genes relating to immune factors directly and indirectly involved in food allergy pathogenesis. We sought to determine potential links between gene expression and epigenetic factors relating to Toll-like receptor (TLR) pathways and childhood food allergies. METHODS: In a cross-sectional study, samples from 80 children with and without food allergies were analysed for gene expression, DNA methylation and a range of immune factors relating to TLR pathways. TLR2, TLR4, CD14, IL5, IL13 and vitamin D were explored. RESULTS: The importance of these immune factors appeared to vary between the different types of food allergies. Expression of TLR2 (P < .001), TLR4 (P = .014) and CD14 (P = .028) varied significantly between children with no food allergy, allergy to nuts and peanuts, and allergy to eggs. DNA methylation in the promoter regions of these genes had a significant association with gene expression. These trends persisted when subjects were stratified by nutallergy vs no nutallergy. Furthermore, TLR2 (P = .001) and CD14 (P = .007) expressions were significantly lower in children with food allergies when compared to those without. CONCLUSION: Gene expression of TLR pathway genes was directly related to food allergy type, and DNA methylation had an indirect effect. TLR2 pathways are of significant interest in nutallergies.