BID and infection: Another study, conducted on the brain of deceased rabies patients, demonstrated immunostained cleaved caspase-3 in microglial cells, which are from the macrophage lineage.18 In our study, we demonstrate that caspases-1/11, -3, -7, -8, and -9, IL-1β and the Bid factor are activated in Mf4/4 cells upon infection with ERA.