IFNAR1 and infection: To determine whether type I IFN signaling was actually involved in B. abortus-induced neuronal loss we pre-incubated neurons/microglia co-cultures with anti-interferon-alpha/beta receptor (IFNAR)1 neutralizing antibodies followed by either infection of microglia with B. abortus or their activation by treatment with culture supernatants from B. abortus-infected astrocytes.