Lactobacillus plantarum NRIC1832 enhances IL-10 production from CD4⁺ T cells in vitro.

The anti-inflammatory effect of lactic acid bacteria (LAB) has been reported in several models for autoimmune diseases. It was considered in those studies that IL-10 induced by LAB might have been involved in such anti-inflammatory activity. We therefore examined the IL-10-inducing activity of LAB in detail by using an in vitro culture system of DO11.10 splenocytes. Most strains of LAB tested in this study increased IL-10 production. A further study using one of the tested strains with potent immune-regulatory activity, Lactobacillus plantarum NRIC1832, showed that the enhanced IL-10 was mainly produced by T cells. However, this enhancement required several types of cells other than T cells. NRIC1832 enhanced IL-10 production after short-term exposure to T cells, but this effect diminished after long-term exposure, indicating that the enhancement of IL-10 production by NRIC1832 was temporary, in contrast to the enhancement of IFN-γ production which was still apparent after long-term exposure.