Modulation Of T Regulatory And Dendritic Cell Phenotypes Following Ingestion Of Bifidobacterium Longum, Ahcc((R)) And Azithromycin In Healthy Individuals

The probiotic Bifidus BB536 (BB536), which contains Bifidobacterium longum, has been shown to have enhanced probiotic effects when given together with a standardized extract of cultured Lentinula edodes mycelia (AHCC((R)), Amino Up Co. Ltd., Sapporo, Japan). BB536 and AHCC((R)) may modulate T cell and dendritic cell (DC) phenotypes, and cytokine profiles to favour anti-inflammatory responses following antibiotic ingestion. We tested the hypothesis that orally administered BB536 and/or AHCC((R)), results in modulation of immune effector cells with polarisation towards anti-inflammatory responses following antibiotic usage. Forty healthy male volunteers divided into 4 equal groups were randomised to receive either placebo, BB536, AHCC((R)) or a combination for 12 days in a double-blind manner. After 7 days volunteers also received 250 mg azithromycin for 5 days. Cytokine profiles from purified CD3+ T cells stimulated with PDB-ionomycin were assessed. CD4+ CD25+ forkhead box P3 (Foxp3) expression and peripheral blood DC subsets were assessed prior to treatment and subsequently at 7 and 13 days. There was no difference in cytokine secretion from stimulated CD3+ T cells between treatment groups. Compared with baseline, Foxp3 expression (0.45 +/- 0.1 vs. 1.3 +/- 0.4; p = 0.002) and interferon-gamma/interleukin-4 (IFN-gamma/IL-4) ratios were increased post-treatment in volunteers receiving BB536 (p = 0.031), although differences between groups were not significant. For volunteers receiving combination BB536 and AHCC((R)), there was an increase in myeloid dendritic cells (mDC) compared with plasmacytoid DC (pDC) counts (80% vs. 61%; p = 0.006) at post treatment time points. mDC2 phenotypes were more prevalent, compared with baseline, following combination treatment (0.16% vs. 0.05%; p = 0.002). Oral intake of AHCC((R)) and BB536 may modulate T regulatory and DC phenotypes to favour anti-inflammatory responses following antibiotic usage.