Toll-like receptor induced pro-interleukin-1beta and interleukin-6 in monocytes are lower in healthy infants compared to adults

Infants have long been known to have higher infectious diseases morbidity and mortality and suboptimal vaccination responses compared to older children and adults. A variety of differences in innate and adaptive immune responses have been described between these two groups. We compared Toll-like receptor (TLR)-induced production of pro-interleukin (IL)-1beta, IL-6, and tumor necrosis factor (TNF)-alpha between 2-month-old infants and adults. TLR 7/8-induced production of pro-IL-1beta and IL-6 in monocytes was lower in 2-month-old infants compared to adults. There was no difference in TLR 7/8-induced production of TNF-alpha. Lower TLR-induced production of pro-IL-1beta and IL-6 in innate immune cells during early infancy likely contributes to suboptimal vaccine responses and infectious diseases susceptibility