Selective effects of Lactobacillus casei Shirota on T cell activation, natural killer cell activity and cytokine production

Abstract

SummaryModulation of host immunity is an important potential mechanism by which probiotics confer health benefits. This study was designed to investigate the effects of a probiotic strain, Lactobacillus casei Shirota (LcS), on immune function using human peripheral blood mononuclear cells (PBMC) in vitro. In addition, the role of monocytes in LcS-induced immunity was also explored. LcS promoted natural killer (NK) cell activity and preferentially induced expression of CD69 and CD25 on CD8+ and CD56 + subsets in the absence of any other stimulus. LcS also induced production of interleukin (IL)-1b, IL-6, tumour necrosis factor (TNF)-a, IL-12 and IL-10 in the absence of lipopolysaccharide (LPS). In the presence of LPS, LcS enhanced IL-1b production but inhibited LPS-induced IL-10 and IL-6 production, and had no further effect on TNF-a and IL-12 production. Monocyte depletion reduced significantly the impact of LcS on lymphocyte activation, cytokine production and natural killer (NK) cell activity. In conclusion, LcS activated cytotoxic lymphocytes preferentially in both the innate and specific immune systems, which suggests that LcS could potentiate the destruction of infected cells in the body. LcS also induced both proinflammatory and anti-inflammatory cytokine production in the absence of LPS, but in some cases inhibited LPSinduced cytokine production. Monocytes play an important role in LcSinduced immunological responses.

Characterisation of the exopolysaccharide (EPS)-producing Lactobacillus paraplantarum BGCG11 and its non-EPS producing derivative strains as potential probiotics

“…Besides, and taking into account the citations reported above, the model used to test the ability of any potential probiotic strain to transiently colonize the GIT is of pivotal relevance. Nowadays, it is well known that probiotics impact on the immune function of humans by inducing T-cell differentiation to Th1, Th2, Th17 or Treg (Dong et al, 2010;López et al, 2011). Therefore, it is claimed that they promote health benefits throughout the regulation of the immune response, However, it is necessary to underline that the immune modulation ability is strictly species-and straindependent (Díaz-Ropero et al, 2007;van Hemert et al, 2010), that for a given strain it is dose-dependent (Evrard et al, 2011) and that well documented probiotics are not effective for all human populations (Seifert et al, 2011).…”

Probiotic Lactobacillus casei Shirota improves kidney function, inflammation and bowel movements in hospitalized patients with acute gastroenteritis – A prospective study

“…The effects of probiotics on immune function are still poorly understood. Some studies show a more or less modulatory effect (Patel, Shukla, & Goyal, 2015) on the innate and adaptive immune system (Castellazzi et al, 2007;Dong et al, 2010). The ability of LcS to promote NK cell activity has also been reported in different studies.…”

“…LcS is able to promote the innate immunity by increasing NK cell activity, and improves inflammatory status by an increasing IL-10/IL-12 ratio. Furthermore, LcS is described to enhance the activity of cytotoxic T lymphocytes (CD8+ T cells) via induction of proinflammatory cytokines (Dong, Rowland, Thomas, & Yaqoob, 2013;Dong, Rowland, Tuohy, Thomas, & Yaqoob, 2010;Nagao et al, 2000).…”

Influence of a probiotic Lactobacillus casei strain on the colonisation with potential pathogenic streptococci and Staphylococcus aureus in the nasopharyngeal space of healthy men with a low baseline NK cell activity

“…Data from previous human intervention studies suggested that in healthy humans, functions of the innate immune system, e.g. the activity of natural killer (NK) cells, may be stimulated by the ingestion of probiotic bacteria [2][3][4][5][6][7][8][9][10][11][12].…”