Indoor Mould Exposure Reduces Th 1 Reactivity in Early Childhood

Abstract

A birth cohort study (LARS - Leipzig Allergy Risk Children Study) was used to investigate the influence of indoor mould exposure on T cell function in early childhood. T cell cytokines (IFN-γ, IL-4) were analysed in a sub-group of the LARS cohort (birth: n = 39, 6 months: n = 11, 12 months: n = 50, 36 months: n = 33). Mould burden was assessed by analysis of questionnaires completed at the birth of the child and measurement of indoor mould spores was carried out when the children were 3 years old. Children whose parents reported mould burden or dampness in their dwellings at the time of birth showed lower amounts of IFN-γ producing Th1 cells during the first year of life (significant at 12 months) in comparison to unexposed children. The capacity to produce IL-4 was not altered, however. When the children were 3 years old, an association between measured indoor mould and suppressed Th1 reactivity was observed. The data suggest that indoor mould exposure is associated with reduced Th1 reactivity in early childhood.