<i>Ex vivo</i> peripheral blood mononuclear cell response to R848 in children after supplementation with the probiotic <i>Lactobacillus acidophilus</i> NCFM/<i>Bifidobacterium lactis</i> Bi-07

Several studies have demonstrated a decrease in upper respiratory infection (URI) frequency and severity subjects taking probiotic supplements. We hypothesised beneficial effects of probiotics on viral URI children are due to modulation inflammatory innate immune responses. tested this hypothesis, providing with combination Lactobacillus acidophilus/Bidfidobacterium animalis ssp. lactis Bi-07 (NCFM/Bi-07) measuring levels cytokines response stimulation peripheral blood mononuclear cells (PBMCs) toll-like receptor (TLR) 7/8 agonist resiquimod (R848). In open label study, 21 (2 dropouts) received containing 5×10 9 cfu each NCFM/(Bi-07) daily for 30 days. Whole was taken from subject at study entry days culture PBMCs. PBMCs stimulated (R848) or unstimulated were incubated panel markers measured. There significant the net (stimulated-null) level myeloid progenitor inhibitory factor 1 (MPIF-1) (mean 0.1 ng/ml, 95% confidence interval 0.01-0.24, P=0.032) following supplementation. The change marker after supplementation, when analysed together respect expected inflammatory/anti-inflammatory effects, increased interleukin (IL)-10 decreased MPIF-1, IL-8, interferon gamma induced protein 10, macrophage 3 alpha (MIP-3α) E-selectin (P=0.01). Adverse events mild. conclusion, supplementation safe resulted PBMC limited TLR7/8 R848 MPIF-1 MIP-3α. anti-inflammatory effect may be one mechanism by which modulate system however further is needed.