IL1B and neoplasm: They found that injection of OMVs one week before tumor vaccination significantly enhanced antitumor immunity in mice, thanks to the trained immunity resulting from pre‐inoculation with OMVs.[111] This study demonstrated that OMVs induced IL‐1β secretion by activating the inflammasome signaling pathways, and the released IL‐1β entered the bone marrow and altered innate immune function, thus exhibiting enhanced immune responses to subsequent tumor vaccination (Figure 6).