TGFB1 and spontaneous abortion: TGF‐β is an anti‐inflammatory cytokine, and its reduction can lead to miscarriage due to disturbance of the immune tolerance environment and defects in placental development.[32] To our surprise, both engineered Exos with biocompatibilities (Figure S11, Supporting Information) mitigated abortion, with the treatment of GC‐Exo‐CD16Ab after LPS challenge demonstrating the most pronounced effect (Figure S12B,C, Supporting Information).