Fig 5.

hsp70 released from Ed MeV-infected N2a-HSP cells can induce IFN-β transcription in a mouse microglial cell line (BV-2). (A) Supernatants harvested from infected (Inf) and uninfected (Uninf) N2a-HSP and N2a-V cells were cocultured with BV-2 cells for 6 h, followed by quantification of IFN-β transcripts in the BV-2 cells by real-time RT-PCR analysis of total cell RNA. Significant induction of IFN-β transcripts was observed in BV-2 cells treated with supernatant recovered from infected N2a-HSP, relative to cells treated with supernatant from uninfected N2a-HSP cells and infected and uninfected N2a-V cells (ANOVA; P < 0.05). (B) Polyclonal rabbit anti-hsp70 IgG (αHSP70), added to culture supernatants from infected N2a-HSP cells, suppressed induction of IFN-β transcripts in BV-2 cells to levels observed in cells cocultured with supernatants derived from uninfected N2a-HSP cells. Significant differences are noted by an asterisk (ANOVA; P < 0.05). Negative-control rabbit total IgG caused a partial nonspecific suppression of IFN induction, although the level of suppression was not statistically significant.