Journal: Veterinary Research

Article Title: Outer membrane vesicles secreted by avian pathogenic Escherichia coli promote its survival within macrophages and systemic infection by inducing endoplasmic reticulum stress-mediated autophagy flux blockade

doi: 10.1186/s13567-025-01679-6

Figure Lengend Snippet: APEC OMVs activate UPR signaling to induce ERS . A HD11 cells were treated with 50–200 µg/mL OMVs for 6 h, and the relative mRNA levels of UPR downstream genes ATF4 , CHOP , EDEM1 , ERdj4 , and ATF6 were detected by qPCR. ( n = 3) B HD11 cells were treated with OMVs (100 µg/mL) for 0–9 h, and qPCR was used to detect the relative mRNA levels of UPR downstream genes ATF4 , CHOP , EDEM1 , ERdj4 , and ATF6 . ( n = 3) C , D HD11 cells were treated with OMVs (100 µg/mL) for 0–9 h, western blotting was used to detect the expression of PERK, p-PERK, eIF2α, p-eIF2α, CHOP, IRE1, p-IRE1, and ATF6 proteins in cell lysates, and gray value analysis was performed using ImageJ software ( D ). ( n = 3). E , F HD11 cells were treated with OMVs (100 µg/mL) for 6 h in the absence or presence of 4-PBA (2 mM), western blot analysis was used to detect the expression of PERK, p-PERK, eIF2α, p-eIF2α, CHOP, IRE1, p-IRE1, and ATF6 proteins in cell lysates, and gray value analysis was performed using ImageJ software ( F ). ( n = 3); n represents three biological replicates; data points indicate independent culture systems. Bar charts display mean ± standard error of the mean (SEM). Two-way ANOVA with Sidak correction was performed (* p < 0.05, ** p < 0.01, *** p < 0.001).

Article Snippet: Rabbit anti-p-IRE1 polyclonal antibody , Abmart, Shanghai, China , 1:5000.

Techniques: Western Blot, Expressing, Software

Journal: Veterinary Research

Article Title: Outer membrane vesicles secreted by avian pathogenic Escherichia coli promote its survival within macrophages and systemic infection by inducing endoplasmic reticulum stress-mediated autophagy flux blockade

doi: 10.1186/s13567-025-01679-6

Figure Lengend Snippet: OMVs secreted by avian pathogenic Escherichia coli promote its survival within macrophages and systemic infection by inducing ERS-mediated autophagy flux blockade . APEC-secreted OMVs, upon uptake by HD11 cells, induce ROS accumulation and Ca 2+ release, triggering ERS and activating UPR pathways, including the PERK, IRE1, and ATF6 signaling branches, leading to the expression of stress-related factors such as GRP78/BiP and CHOP. The sustained activation of ERS inhibits autophagosome degradation and disrupts the acidic environment of lysosomes, thereby preventing autophagosomes from fusing with lysosomes and impairing the phagocytic clearance capacity of macrophages. Collectively, these abnormal conditions facilitate APEC survival within HD11 cells and enable immune evasion, ultimately promoting bacterial dissemination and systemic infection in the host.

Article Snippet: Rabbit anti-p-IRE1 polyclonal antibody , Abmart, Shanghai, China , 1:5000.

Techniques: Infection, Expressing, Activation Assay