Immunostimulatory Effects Triggered by Enterococcus faecalis CECT7121 Probiotic Strain Involve Activation of Dendritic Cells and Interferon-Gamma Production

Abstract

Probiotics can modulate the immune system, conferring beneficial effects on the host. Understanding how these microorganisms contribute to improve the health status is still a challenge. Previously, we have demonstrated that Enterococcus faecalis CECT7121 implants itself and persists in the murine gastrointestinal tract, and enhances and skews the profile of cytokines towards the Th1 phenotype in several biological models. Given the importance of dendritic cells (DCs) in the orchestration of immunity, the aim of this work was to elucidate the influence of E. faecalis CECT7121 on DCs and the outcome of the immune responses. In this work we show that E. faecalis CECT7121 induces a strong dose-dependent activation of DCs and secretion of high levels of IL-12, IL-6, TNFα, and IL-10. This stimulation is dependent on TLR signaling, and skews the activation of T cells towards the production of IFNγ. The influence of this activation in the establishment of Th responses in vivo shows the accumulation of specific IFNγ-producing cells. Our findings indicate that the activation exerted by E. faecalis CECT7121 on DCs and its consequence on the cellular adaptive immune response may have broad therapeutic implications in immunomodulation.

Probiotic activity of Enterococcus faecalis CECT7121: effects on mucosal immunity and intestinal epithelial cells

“…faecalis CECT7121‐treated mice did not proliferate when this strain was employed as stimulus (Molina et al . ). The lack of specific proliferation in both lymphoid organs could be in line with the capacity of this probiotic bacterium to behave as a commensal micro‐organism without inducing uncontrolled inflammatory responses.…”

Efficacy of probiotic treatment with Bifidobacterium longum 536 for induction of remission in active ulcerative colitis: A randomized, double‐blinded, placebo‐controlled multicenter trial

“…Another factor regarding response to BB536 treatment is the dosage. Recently, several studies have reported dose‐dependent effects of probiotics on the immune response in vitro and in vivo . Therefore, we speculate that treatment with an increased dose of BB536 may more clearly exhibit positive clinical effects.…”

“…Recently, several studies have reported dose-dependent effects of probiotics on the immune response in vitro and in vivo. [19][20][21][22] Therefore, we speculate that treatment with an increased dose of BB536 may more clearly exhibit positive clinical effects. Consequently, our data demonstrated that addition of BB536 to standard treatment was effective in inducing remission in a subpopulation of Japanese patients with mild to moderately active UC.…”

Polyphasic characterization of Enterococcus strains isolated from traditional Moghan cheese in Iran

“…A few strains are also being marketed as probiotics adjuncts, contributing to GIT health by improving the microbial balance following diarrhea or antibiotic associated diarrhea (Franz, Huch, Abriouel, Holzapfel, & Gálvez, ; Tarasova et al, ). Other beneficial effects of Entrococci include their antiviral activity (Wang et al, ), protective antitumor effect (Castro et al, ), ability to lower cholesterol by excretion of deconjugated bile salts (Guo, Li, Tang, Yang, & Huo, ), and immune modulation (Molina et al, ). Currently, the only species within the Enterococcus genus that are intended for use as probiotics in the human and animal are E. faecalis and Enterococcus faecium (Franz et al, ).…”