Fig. 6.

APCs pre-stimulated with LA do not enhance OVA-specific cytokine production by CD4⁺ T cells. MLN CD4⁺ cells (5 × 10⁵ cells) from OVA23-3 mice were cultured in 48-well flat-bottom plates in the absence or the presence of OVA and intestinal bacteria with MLN Thy1.2⁻ cell (2 × 10⁶ cells) from Balb/c mice as APCs. In the pre-stimulation condition, Thy1.2⁻ cells and intestinal bacteria were co-cultured for 24 h, and then the supernatants were removed by centrifugation, and CD4⁺ cells and OVA were added. In the simultaneous stimulation, CD4⁺ cells, OVA and intestinal bacteria were added to the Thy1.2⁻ cell culture simultaneously. Final concentration of intestinal bacteria (LA or BA) in the culture was 50 μg/ml, and OVA was added at 250 μg/ml. The supernatants were assayed for cytokines (IFN-γ, IL-10) by ELISA. All data represent mean ± S.D. *Significant differences between non-stimulated cells (medium) and the cells stimulated with bacteria (p < 0.05). Data shown are representative of 3 independent experiments