IL1B and Flavivirus Infections: To determine whether the addition of microglial cells to BS modulates the immune response against flavivirus infection, the levels of intracellular TNF-α, CCL2, IL-1b, and IL-6 mRNA were measured in sole microglia, BS, and μBS 72 h after exposure to DENV-1, ZIKV-UG, and ZIKV-BR.