Dietary supplementation with Bifidobacterium lactis NCC2818 from weaning reduces local immunoglobulin production in lymphoid-associated tissues but increases systemic antibodies in healthy neonates

摘要

Weaning is associated with a major shift in the microbial community of the intestine, and this instability may make it more acquiescent thanudthe adult microbiota to long-term changes. Modulation achieved through dietary interventions may have potentially beneficial effects onudthe developing immune system, which is driven primarily by the microbiota. The specific aim of the present study was to determineudwhether immune development could be modified by dietary supplementation with the human probiotic Bifidobacterium lactisudNCC2818 in a tractable model of weaning in infants. Piglets were reared by their mothers before being weaned onto a solid dietudsupplemented with B. lactis NCC2818, while sibling controls did not receive supplementation. Probiotic supplementation resulted inuda reduction in IgA (P,0·0005) and IgM (P,0·009) production by mucosal tissues but had no effect on IgG production (P.0·05). Probiotic-udsupplemented pigs had more mast cells than unsupplemented littermates (P,0·0001), although numbers in both groups were low. Inudaddition, the supplemented piglets made stronger serum IgG responses to fed and injected antigens (P,0·05). The present findings areudconsistent with B. lactis NCC2818 reducing intestinal permeability induced by weaning, and suggest that the piglet is a valuableudintermediate between rodent models and human infants. The results also strongly suggest that measures of the effect of probiotic supplementationudon the immune system need to be interpreted carefully as proxy measures of health benefit. However, they are useful inuddeveloping an understanding of the mechanism of action of probiotic strains, an important factor in predicting favourable health outcomesudof nutritional intervention.