Folate status, regulatory T cells and MTHFR C677T polymorphism study in allergic children

Purpose: This study aimed to investigate early-life folate serum concentrations in children with food, inhalant or mixed type allergy. The influence of folate levels on the FoxP(3) expression in Treg (regulatory T) cells in the studied children, taking into account the MTHFR (5,10-methylenetetrahydrofolate reductase) genotypes was also analyzed. Material and methods: The study was performed in 83 allergic children (study group) and 49 healthy children (control group), aged 2-72 months. Medical history of each child was obtained and laboratory tests (serum folic acid concentrations and MTHFR C677T polymorphism) were carried out. The percentage of Treg cells was evaluated in almost a half of the examined subjects (48.5%). Results: Significantly higher serum folate levels in the group of children with food allergy than in those with inhalant allergy was confirmed (P = 0.037). In the study group the TT homozygotes were characterized by significantly lower folate concentrations than CC homozygotes (P = 0.045). A negative correlation was demonstrated between the FoxP(3) expression in CD4(+) CD25(high)FoxP3(+) peripheral blood lymphocytes and serum folic acid concentrations. The correlation was more pronounced in the group of allergic children and it was statistically significant (r = -0.339, P < 0.05). Conclusions: The results of the study indicate a possibility of some effects of folate status on Treg cells, thus suggesting their potential role in the development and course of allergy in children. (C) 2016 Medical University of Bialystok. Published by Elsevier Sp. z o.o. All rights reserved.