Prevention of B220+ T cell expansion and prolongation of lifespan induced by Lactobacillus casei in MRL/lpr mice

Clin Exp Immunol. 1999 Aug;117(2):368-75. doi: 10.1046/j.1365-2249.1999.00951.x.


We examined the therapeutic effect of heat-killed Lactobacillus casei (LC) on MRL/lpr mice. Ingestion of a diet containing 0.05% (w/w) LC from the weaning period prolonged the lifespan and tended to reduce the proportion of B220+ T cells in the spleen and mesenteric lymph nodes (MLN) of MRL/lpr mice. When LC was intraperitoneally injected once a week after the age of 8 weeks, I-A- macrophages accumulated in the spleen as well as the peritoneum and macrophage progenitors increased in the bone marrow. Moreover, the amount of IL-6 mRNA in peritoneal macrophages was reduced by LC injection. Splenocytes from LC-injected MRL/lpr mice exhibited lower proliferative responses to mitogens than those from control MRL/lpr mice and the increase in number of B220+ T cells in the spleen and MLN was prevented by LC injection. However, LC injection affected neither expression of interferon-gamma (IFN-gamma) and IL-4 mRNAs nor proliferative capacities of splenic T cells. Our findings demonstrate that LC injection accelerates macrophage recruitment and prevents the expansion of B220+ T cells without affecting the functions of T cells in MRL/lpr mice. These immunological modulations induced by LC may lead to prolongation of the lifespan of MRL/lpr mice.

MeSH terms

  • Administration, Oral
  • Animals
  • Animals, Newborn / growth & development
  • Bone Marrow Cells / cytology
  • Bone Marrow Cells / immunology
  • Bone Marrow Cells / microbiology
  • Cell Division / immunology
  • Diet
  • Female
  • Injections, Intraperitoneal
  • Lacticaseibacillus casei / immunology*
  • Leukocyte Common Antigens / immunology*
  • Longevity / immunology*
  • Lymphatic Diseases / immunology
  • Lymphatic Diseases / microbiology
  • Lymphatic Diseases / prevention & control*
  • Lymphocyte Activation
  • Macrophages / cytology
  • Macrophages / immunology
  • Macrophages / microbiology
  • Mice
  • Mice, Inbred MRL lpr
  • Sodium Chloride / administration & dosage
  • Stem Cells / cytology
  • Stem Cells / immunology
  • Stem Cells / microbiology
  • T-Lymphocyte Subsets / cytology*
  • T-Lymphocyte Subsets / immunology*
  • T-Lymphocyte Subsets / microbiology


  • Sodium Chloride
  • Leukocyte Common Antigens