Probiotics and innate immune response in infants
2014 (English)Manuscript (preprint) (Other academic)
We studied the effects of probiotic treatment on the innate immune system during infancy. The study included a subgroup of infants recruited to the pilot study testing the feasibility of probiotics intervention in infants with genetic risk of type 1 diabetes (T1D). A mixture of Lactobacillus rhamnosus GG (5 x 109 cfu), Lactobacillus rhamnosus LC705 (5 x 109 cfu), Bifidobacterium breve Bbi99 (2 x 108 cfu) and Propionibacterium freudenreichii ssp. Shermani JS (2 x 109 cfu) was given to the infants beginning one to three weeks after birth until the age of 6 months. Blood samples were drawn at the age of 6, 12 and 24 months for the analyses of beta-cell autoantibodies and the phenotype and stimulation response of monocytes with flow-cytometry, including surface markers on circulating CD14+ monocytes and expression of co-stimulatory markers on CD14+ monocytes as response to stimulation with lipoteichoic acid (LTA) and lipopolysaccharide (LPS). Also gene expression of toll-like receptor (TLR) signalling molecules was studied in the peripheral blood mononuclear cell (PBMC) population.
In the children who received probiotics the number of circulating CD14+ monocytes expressing CD58 was reduced at the age of 6 months, and a tendency for a decreased induction of CCR5, CD80 and CD58 expressing monocytes as response to LTA was seen when compared to the children who received placebo. At the age of 12 months, the number of monocytes expressing CCR5 was decreased in the probiotic group, and a decreased spontaneous expression of TNFRSF1A and an increased spontaneous expression of TLR9 was observed in the PBMC from the children treated with probiotics. In the whole study group, the numbers of circulating monocytes expressing CD80 increased with age as well as the induction of CCR5, CD80 and CD58 on monocytes as response to stimulation. By the age of 24 months one child in both groups developed multiple autoantibodies.
We demonstrated that probiotics modulated the activation stage and stimulation response of monocytes, and that prolonged effects of the treatment were seen at the age of 12 months. The findings suggest that early microbial exposure may program the function of the innate immune system for later life.
Place, publisher, year, edition, pages
Probiotics, monocytes, innate immunity, TLR, LTA, LPS
Clinical Medicine Pharmacology and Toxicology
IdentifiersURN: urn:nbn:se:liu:diva-110686OAI: oai:DiVA.org:liu-110686DiVA: diva2:748367