IL-15 and macrophage secretory factors facilitate immune activation of neonatal natural killer cells by lipoteichoic acid

摘要: Neonates possess a relatively "naive", yet inducible immune system. Our hypothesis is that upon strategic antigen exposure, cytokine priming and sensitization by accessory cells, natural killer (NK) cells could be activated to become functional phenotype. We investigated the in vitro stimulation of cord blood (CB) adult NK challenge with lipoteichoic acid (LTA), interleukin (IL)-15 LTA-primed autologous macrophage-conditioned medium, using CD107a CD69 phenotypes as indicators activation. also examined response CB macrophages LTA, terms P44/42 extracellular signal-regulated kinases (ERK1/2) activation secretion. LTA significantly induced secretion inflammatory cytokines tumor necrotic factor (TNF)-α, IL-6, IL-12 upstream signal ERK1/2 phosphorylation neonatal macrophages. The magnitude responses differed between cells. Co-stimulation IL-15 was critical for expansion subpopulations both challenge. cell enhanced through secretory factors. results indicated can evoke immunologic Gram-positive bacterial antigen. combinatory strategy relevant development novel protocols, such treatment, compensate immaturity innate system newborns against infections.