ABSTRACT
Background: Mutations in the filaggrin gene (FLG ) affect
epidermal barrier function and increase the risk of atopic dermatitis
(AD). We hypothesized that FLG mutations affect immune cell
composition in a general pediatric population. Therefore, we
investigated if school-aged children with and without FLGmutations have differences in immune cell numbers.
Methods: This study was embedded in a population-based
prospective cohort study, the Generation R Study, and included 523
children of European genetic ancestry aged 10 years. The most commonFLG mutations in the European population (R501X, S1085CfsX36,
R2447X and S3247X) were genotyped. Additionally, 11-color flow cytometry
was performed on peripheral blood samples to determine helper T (Th),
regulatory T (Treg) and CD27+ and
CD27- memory B cells. Sensitivity analysis was
performed in 102 AD cases, assessed by parental questionnaires.
Results: FLG mutations were observed in 8.4% of the
total population and in 15.7% of the AD cases. Children with anyFLG mutation had higher Th22 cell numbers compared to FLGwild-type children. Children with and without FLG mutations had
no difference in Th1, Th2, Th17, Treg or memory B cell numbers.
Furthermore, in children with AD, FLG mutation carriership was
not associated with differences in T- and B-cells or their subsets.
Conclusions: School-aged children with FLG mutations
have higher Th22 cell, which might suggest an immunological defense
mechanism to an altered skin barrier function. No associations between
Th or Treg cells and FLG mutations suggests that FLGmutations do not otherwise affect immune composition in a general
pediatric population.