L. plantarum WCFS1 enhances Treg frequencies by activating DCs even in absence of sampling of bacteria in the Peyer Patches

• Published in: Scientific reports Vol. 8; no. 1; pp. 1785 - 10
• Main Authors: Bermudez-Brito, Miriam, Borghuis, Theo, Daniel, Catherine, Pot, Bruno, de Haan, Bart J., Faas, Marijke M., de Vos, Paul
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 29.01.2018; Nature Publishing Group
• Subjects: 13; 13/1; 13/21; 13/31; 13/51; 14/63; 59/5; 631/250/262; 631/326/41; Animals; Bacteria; CD103 antigen; Cytokines - immunology; Dendritic Cells - immunology; Food and Nutrition; Helper cells; Humanities and Social Sciences; Immune response; Immunology; Immunomodulation; Immunomodulation - immunology; Immunoregulation; Immunotherapy; Intestine; Intestines - microbiology; Lactobacillus plantarum - immunology; Life Sciences; Lymphocytes T; Male; Mice; Mice, Inbred BALB C; multidisciplinary; Peyer's Patches - immunology; Plant cells; Probiotics; Probiotics - pharmacology; Sampling; Science; Science (multidisciplinary); Spleen; Spleen - immunology; T cell receptors; T-Lymphocytes, Helper-Inducer - immunology; T-Lymphocytes, Regulatory - immunology
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-018-20243-1

Probiotics such as L . plantarum WCFS1 can modulate immune responses in healthy subjects but how this occurs is still largely unknown. Immune-sampling in the Peyer Patches has been suggested to be one of the mechanisms. Here we studied the systemic and intestinal immune effects in combination with a trafficking study through the intestine of a well-established immunomodulating probiotic, i.e. L . plantarum WCFS1. We demonstrate that not more than 2–3 bacteria were sampled and in many animals not any bacterium could be found in the PP. Despite this, L . plantarum was associated with a strong increase in infiltration of regulatory CD103 + DCs and generation of regulatory T cells in the spleen. Also, a reduced splenic T helper cell cytokine response was observed after ex vivo restimulation. L . plantarum enhanced Treg cells and attenuated the T helper 2 response in healthy mice. We demonstrate that, in healthy mice, immune sampling is a rare phenomenon and not required for immunomodulation. Also in absence of any sampling immune activation was found illustrating that host-microbe interaction on the Peyer Patches was enough to induce immunomodulation of DCs and T-cells.