IER3 and brucellosis: Of these, Casp4, Ier3, Ifi204, Ltb, Nfkbia, Tnf, Xaf1, and Zc3h12a were also categorized as being associated with apoptosis, which plays a major role in responses to brucellosis by exposing the bacterium to the extracellular environments, where it encounters immune system components such as antibodies and the complement system, thereby reducing bacterial replication [6, 14, 15, 31].