In addition, the induction of ER stress by AIEC may further potentiate the mucosal enrichment of AIEC by inducing the expression of host cell receptors for AIEC outer membrane vesicles (OMVs) such as Gp96 and CEACAM6 on the apical surface of IECs as previously described.45 Once inflammation is established, inflammatory metabolites can also support AIEC expansion.46 Collectively, these findings highlight an additional contribution of ER stress to ileocolitis by promoting and reinforcing AIEC expansion. Here, HSP90B1 is linked to ileocolitis.