Activation of CD1d-independent NK1.1+ T cells in the large intestine by Lactobacilli

Immunol Lett. 2006 Jan 15;102(1):74-8. doi: 10.1016/j.imlet.2005.07.003. Epub 2005 Aug 2.


Among digestive organs, the liver and the large intestine are abundant in T cells expressing NK1.1. NK1.1+ T cells in the liver are mostly CD1d-dependent whereas those in the large intestine are CD1d-independent. In this study, we investigated the effects of Lactobacilli on NK1.1+ T cells in the digestive organs of mice. C57BL/6 mice were orally given a dietary supplement prepared from mixed cultures of eight strains of Lactobacilli. Oral administration of Lactobacilli to mice resulted in the selective expansion of NK1.1+ T cells in the large intestine. These colon NK1.1+ T cells activated by Lactobacilli were found to express IFN-gamma mRNA. The level of IFN-gamma in the serum was also elevated by the administration of Lactobacilli. Our results suggest that Lactobacilli selectively activate CD1d-independent NK1.1+ T cells in the large intestine to produce IFN-gamma and therefore modulate Th1 immune responses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, CD1 / metabolism
  • Antigens, Ly
  • Antigens, Surface / metabolism*
  • Cytokines / blood
  • Cytokines / genetics
  • Dietary Supplements
  • Intestine, Large / drug effects
  • Intestine, Large / immunology*
  • Intestine, Large / metabolism
  • Lactobacillus / immunology*
  • Lectins, C-Type / metabolism*
  • Lymphocyte Activation / immunology*
  • Mice
  • Mice, Inbred C57BL
  • NK Cell Lectin-Like Receptor Subfamily B
  • Organ Specificity
  • Phenotype
  • RNA, Messenger / genetics
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism


  • Antigens, CD1
  • Antigens, Ly
  • Antigens, Surface
  • Cytokines
  • Klrb1c protein, mouse
  • Lectins, C-Type
  • NK Cell Lectin-Like Receptor Subfamily B
  • RNA, Messenger