Preconceptional immunization with an allergen inhibits offspring thymic Th17 cells maturation without influence on Th1 and Th2 cells

The mechanisms through which maternal immunization can modulate offspring thymic maturation of lymphocytes are not fully understood. Here, we aimed to evaluate whether maternal OVA-immunization can inhibit the maturation of Th17 cells on offspring thymus. C57BL/6 females were immunized with OVA in Alum or Alum alone and mated with normal WT males. Offspring thymus was evaluated at three or 20 days of age. The demonstration that maternal OVA-immunization can inhibit offspring allergy development validated our experimental protocol. First, we observed that maternal OVA-immunization can inhibit the expression of RORγT and IL-17 molecules on immature T cells (CD4+CD8+) and TCD4 cells (CD4+CD8−) without interference on TCD8 cells (CD4−CD8+) on three-day-old offspring. A very similar effect could be observed on 20-day-old offspring. Additionally, a Th2 skewed profile could be found on the spleen of immunized pups from OVA-immunized mothers, but no influence was detected on offspring thymic Th1/Th2 profiles. Together, these data demonstrate that maternal immunization with an allergen can modulate offspring thymic maturation of Th17 cells without influencing Th1/Th2 patterns.