Anti-GalNAcβ: A novel anti-glycan autoantibody associated with pregnancy loss in women with antiphospholipid syndrome and in a mouse experimental model

► We detected several anti-glycan Abs (aGA) in patients with antiphospholipid syndrome (APS). ► Anti-GalNAc-β was associated with APS pregnancy loss, but not with thrombotic manifestations. ► Infusion of affinity-purified anti-GalNAc-β to naive mice induced high rate of fetal resorptions. ► Anti-GalNAc-β inhibited choriocarcinoma cells invasiveness and decreased MMP2 & MMP9 secretion.