[Expression profile analysis of intestinal Caco-2 cells treated with Lactobacillus acidophilus NCFM]

Lactobacillus acidophilus NCFM is a probiotic strain that promotes human health. We evaluated the influence of Lactobacillus acidophilus NCFM on the genetic expression patterns in the Caco-2 cells.

Caco-2 cells were treated with Lactobacillus acidophilus NCFM for 2h. The total RNA of cells was extracted. Hybridization with Human Genome U133 Plus 2.0 Array was performed. The image scanning and data analysis were performed subsequently. Genes with significant expression changes were selected and analyzed. To support the microarray data, three striking difference genes were studied using Real-time RT PCR.

Microarrays analysis showed that the expression levels of 508 genes were altered as compared with the control 473 of them were up-regulated, and 35 were down-regulated. It was supposed that many genes in Caco-2 cell were induced, so that Lactobacillus acidophilus NCFM could play a part in immune system process, antioxidant activity, biological adhesion, cholesterol absorption and so on. Three striking difference genes CCL2, PTX3 and TNFRSF9 which involved immune system process were validated by Real-time RT PCR. And the results of Real-time RT PCR showed the same expression trend as in microarray.

Based on the results of gene expression alterations, the beneficial function of Lactobacillus acidophilus NCFM could be more greatly and deeply understood than ever before, and the mechanism of lactic acid bacteria would be revealed.