Fig. 4. Effects of meformin on the expression of MHC molecules. (A) DC2.4 cells and (B) BM-DCs were incubated with metformin (8 mM) for 2 h, and harvested by gentle pipetting. The expression levels of class I and class II MHC molecules were assessed using anti-H-2K^b and anti-I-A^b monoclonal antibodies.