Memory T cell responses primed by neonatal nasal vaccination shifted from Th2 to Th1 cytokine profile when CpG were added as adjuvant.

(a)Neonates were immunised i.n. at age 5–7 days as indicated (prime) and received one intranasal boost with N (10 µg) at 5 weeks.(b)Spleen and cervical lymph node (LN) were collected 7 days after the boost (LN were pooled from 2 to 3 mice). Single cell suspensions were cultured with N, PMA-ionomycin or medium for 72 hours.(c)Culture supernatants were assayed by ELISA for IFNγ and IL5.(d)Cytokine concentrations in supernatants from cultures restimulated with N (mean pg/mL ±SEM for n≥2 for spleen and pool of 2 for LN). (All cell cultures responded to PMA, producing 39838±8542 pg/mL IFNγ).