A novel kefir product (PFT) activates dendritic cells to induce CD4+T and CD8+T cell responses in vitro

Int J Immunopathol Pharmacol. 2015 Dec;28(4):488-96. doi: 10.1177/0394632015599447. Epub 2015 Sep 17.


Lactobacilli have been widely studied for their probiotic effects and have been reported to function as antiviral and anticancer agents. However, the underlying mechanisms via immune modulation are poorly understood. PFT is a freeze dried compound of Lactobacillus kefiri P-IF with a unique composition and functionality. In this study, we examined the potential stimulatory effects of two concentrations (50 µg and 100 µg/mL) of PFT on human monocyte-derived dendritic cell (DC) function in vitro. Results showed that PFT upregulated the expression of DC surface co-stimulatory and maturation markers CD80, CD86, and HLADR in a concentration dependent manner. PFT at 100 µg/mL markedly increased the secretion of IL-6, IL-10, TNF-α, and IL-1β by DCs. This concentration of PFT also stimulated the production of antiviral cytokines, IFN-α and IFN-λ(IL29) in DCs. Additionally, PFT at 100 µg/mL activated moDCs prime CD4(+)T cells and significantly increased the levels of IL-10, IFN-γ, and TNF-α by 1.7, four, three-fold, respectively. Furthermore PFT-stimulated DCs were also effective in enhancing the cytotoxic potential of CD8(+)T cells via the induction of Granzyme-B and upregulation of CD107a, and CD103 expression, a marker of resident/regulatory CD8(+)T cells. These data suggest that PFT functions as a natural adjuvant for DC activation and thus may be used in DC-based vaccine strategies against viral infections and cancer.

Keywords: CD8 T cells; PFT; dendritic cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, CD / analysis
  • CD4-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Cytokines / metabolism
  • Dendritic Cells / drug effects*
  • Dendritic Cells / immunology
  • Humans
  • Integrin alpha Chains / analysis
  • Lactobacillus*
  • Lysosomal-Associated Membrane Protein 1 / analysis
  • Probiotics / pharmacology*


  • Antigens, CD
  • Cytokines
  • Integrin alpha Chains
  • Lysosomal-Associated Membrane Protein 1
  • alpha E integrins