E-GEOD-41127 - Gene expression profile in the spleen of mice fed Lactobacillus brevis KB290
Released on 5 August 2013, last updated on 2 June 2014
Lactic acid bacteria confer a variety of health benefits. Here we investigate the mechanisms by which Lactobacillus brevis KB290 enhances cell-mediated cytotoxic activity. We fed a diet containing KB290 (3 × 10^9 colony-forming units/g) , or potato starch, to 9-week-old female BALB/c mice for 1, 4, 7, or 14 days and examined the cytotoxic activity of splenocytes was measured. RNA was extracted from the spleen and analyzed for gene expression by DNA microarray. KB290 enhanced the cell-mediated cytotoxic activity of splenocytes. The Gene Ontology (GO) terms related to immune process were significantly enriched in up-regulated gene set for 7 days and the GO terms related to cellular process were enriched in down-regulated gene set on days 4 and 7. Among the GO terms related to immune process, positive regulation of T cell-mediated cytotoxicity was existed. Almost all of the genes included in the term encoded MHC class I molecules, which are involved in the presentation of antigen to CD8+ cytotoxic T cells. On the other hand, the over-represented Kyoto Encyclopedia of Genes and Genomes pathways among the up-regulated genes were those for natural killer cell-mediated cytotoxicity and antigen processing and presentation on day 1. Although the up-regulated genes involved in antigen processing and presentation for stimulation of CD8+ cytotoxic T cells were not observed on day 14, some genes involved in T cell and natural killer cell activation remained up-regulated until day 14. The sequential gene expression profiling reflected the changes in cytotoxic activity during KB290 feeding. These results suggest that the enhanced cytotoxic activity could have been caused both by activation of natural killer cells and by CD8+ cytotoxic T cells stimulated via MHC class I presentation. Specific-pathogen-free female BALB/c mice, aged 8 weeks, were purchased from Charles River Laboratories Japan, Inc. They (n = 48) were divided into two groups, control and KB290 (4 cages per group) with equal mean body weights. They were allowed to free access to a commercial normal diet CE-2 (CLEA Japan, Inc.) and sterile water during one-week acclimation period. Then, they received lyophilized KB290 for the treatment group diet (3x109 cfu/g) or 5.8% (w/w) potato starch (Nippon Starch Chemical) for the control group diet for 1, 4, 7, and 14 days. Daily intake of KB290 containing diet per treated mouse was 3.99g, or about 1 × 1010 cfu. On day 1, 4, 7, and 14, six mice in each group were euthanized and their spleens were sampled for Cell-mediated cytotoxicity and DNA microarray assay.
transcription profiling by array
Erika Sasaki, Keiko Abe, Nobuhiro Yajima, Nobuo Fuke, Tomoko Ishijima, Yuichiro Fukui, Yuji Nakai
Effect of Lactobacillus brevis KB290 on the cell-mediated cytotoxic activity of mouse splenocytes: a DNA microarray analysis. Fukui Y, Sasaki E, Fuke N, Nakai Y, Ishijima T, Abe K, Yajima N. , Europe PMC 23544404