Differential modulation of innate immunity in vitro by probiotic strains of Lactobacillus gasseri

Abstract

BackgroundProbiotics species appear to differentially regulate the intestinal immune response. Moreover, we have shown that different immune-modulatory abilities can be found among probiotic strains belonging to the same species. In this study, we further addressed this issue while studying L. gasseri, a species that induces relevant immune activities in human patients.ResultsWe determined the ability of two strains of L. gasseri, OLL2809 and L13-Ia, to alter cell surface antigen expression, cytokine production and nuclear erythroid 2-related factor 2 (Nrf2)-mediated cytoprotection in murine bone marrow-derived dendritic cells (DCs) and MODE-K cells, which represent an enterocyte model. Differential effects of L. gasseri strains were observed on the expression of surface markers in mature DCs; nevertheless, both strains dramatically induced production of IL-12, TNF-α and IL-10. Distinctive responses to OLL2809 and L13-Ia were also shown in MODE-K cells by analyzing the expression of MHC II molecules and the secretion of IL-6; however, both L. gasseri strains raised intracellular glutathione. Treatment of immature DCs with culture medium from MODE-K monolayers improved cytoprotection and modified the process of DC maturation by down-regulating the expression of co-stimulatory markers and by altering the cytokine profile. Notably, bacteria-conditioned MODE-K cell medium suppressed the expression of the examined cytokines, whereas cytoprotective defenses were significantly enhanced only in DCs exposed to OLL2809-conditioned medium. These effects were essentially mediated by secreted bacterial metabolites.ConclusionsWe have demonstrated that L. gasseri strains possess distinctive abilities to modulate in vitro DCs and enterocytes. In particular, our results highlight the potential of metabolites secreted by L. gasseri to influence enterocyte-DC crosstalk. Regulation of cellular mechanisms of innate immunity by selected probiotic strains may contribute to the beneficial effects of these bacteria in gut homeostasis.

Modulatory activity of Lactobacillus rhamnosus OLL2838 in a mouse model of intestinal immunopathology

“…More recently, microbial productions of butyrate and niacin have been associated to the induction of anti-inflammatory properties in phagocytes (Singh et al, 2014). In line with these data, we recently demonstrated the ability of metabolites secreted by L. gasseri to influence the crosstalk between enterocyte and DCs that may contribute to the beneficial effects of these bacteria in gut homeostasis (Luongo et al, 2013).…”

Effects of Lactobacillus acidophilus dietary supplementation on the performance, intestinal barrier function, rectal microflora and serum immune function in weaned piglets challenged with Escherichia coli lipopolysaccharide

“…As mentioned before, at weaning, piglets are stressed, the food intake is strongly depressed, the structure and function of the gastrointestinal tract are altered, and these conditions can favor bacterial translocation, inflammation, and infection with pathogenic bacteria (Villena and Kitazawa 2014). Two strains of Lactobacilus gasseri exhibited similar antimicrobial behavior that could derive by lactic acid production or hydrogen dioxide (H 2 O 2 ), both molecules usually released by lactobacilli during their growth (Luongo et al 2013). It was shown that the probiotic strain Lactobacilus plantarum CJLP243 may serve as a potential alternative to antibiotic supplementation to improve the growth and health performance of weaning pigs because of its capacity to reduce the severity of ETEC-induced diarrhea (Lee et al 2012).…”

“…Our findings of serum IL-10 level upregulation of piglets challenged with LPS was consistent with these previous studies. Luongo et al (2013) analyzed the effects of irradiated bacteria on the cytokine profile of the DCs, and they found LPS induced maturation of DCs derived from this mouse strain and increased the secretion of IL-12 and TNF-a, but not of IL-10. Notably, in vitro challenge with both Lactobacilus gasseri dramatically enhanced the expression of all examined cytokines including IL-10, showing significant differences with the positive control (mDCs alone) (Luongo et al 2013).…”

“…Luongo et al (2013) analyzed the effects of irradiated bacteria on the cytokine profile of the DCs, and they found LPS induced maturation of DCs derived from this mouse strain and increased the secretion of IL-12 and TNF-a, but not of IL-10. Notably, in vitro challenge with both Lactobacilus gasseri dramatically enhanced the expression of all examined cytokines including IL-10, showing significant differences with the positive control (mDCs alone) (Luongo et al 2013). The increases of serum IL-10 was important because it reflected the changes of the main inductor sites for mucosal immune responses, like Peyer's patches and lamina propria (Castillo et al 2011).…”

Lactic acid bacteria with probiotic potential from Nellore calves raised in semiarid

“…Espécies probióticas podem melhorar a resposta imune intestinal, contribuindo com efeitos benéficos na microbiota autoctone intestinal (Luongo et al, 2013). A implementação de probióticos na dieta contribui para melhor crescimento dos bezerros e na diminuição de diarreia (Bayatkouhsar et al, 2013;Soto et al, 2014).…”