IL1B and infection: Several animal studies have demonstrated thefundamental role pro-inflammatory cytokines, especially interleukin (IL)-1β, play inthis response.8 In conditions with infection and/or tissue injury, activation of innateimmunity cells will rapidly lead to increased production of IL-1β which pass throughthe blood–brain barrier (BBB) and reaches neuronal cells in the brain by bothpassive and active transport systems and can even be produced intrathecally.