Microglial response to necrotic neurons is MyD88-dependent. (A) Microglial cells derived from MyD88-deficient mice were stimulated with necrotic HT22 cells for 24 hours and the expression of CD40 and MHC class II was assessed and compared to that of wild type cells. Pam3CSK4 is a TLR-2 ligand; ND, non-detectable. (B) The levels of IL-6 and IL-12 were quantified in the supernatants of microglial cell cultures by ELISA. (C) Induction of CD40 expression in TLR-2 or TLR-4 deficient microglia stimulated with necrotic neurons. LPS is a specific ligand for TLR-4. Results are shown as mean ± SD of three independent experiments or are representative of at least two experiments. *** p < 0.001; **p < 0.01 and * p < 0.05.