However, a peak in cell numbers was identified at two years of age when levels reached a significantly higher frequency than those seen at 12 weeks after birth ( p = 0.0313), one year ( p = 0.0313), and almost reached significance at three years of age ( p = 0.0625) as animals matured.
The frequency of classical (CD14 + ) monocytes showed a trend to decrease ( p = 0.0625) during the first 20 weeks after vaccination, while the frequency of non-classical monocytes, which are involved in T-cell stimulation and inflammatory cytokine release ( 38 ), showed a trend ( p = 0.0625) to increase over the same period of time.
The concentrations of growth factor, FGF-2 and cytokines IL-4, IL-5, IL-15 and TNF-α were also found to be significantly higher ( p < 0.05 or close to significance, p = 0.0699, for IL-17A) after vaccination in the adult group.