EMBO/SourceData huggingface dataset:
Figure 2A. Nucleosomes (N) decorating a relaxed plate (P1); insets in the upper right show additional examples. Nucleosomes are not visible as individual units in typical compact plates (P2). Short compact interdigitated solenoids are shown in the main image (S) and in the bottom-left insets. Data information: Scale bars: 50 nmB-E Slice (B) and segmentations in three different orientations (C) of a large relaxed plate decorated with many nucleosomes on its right side. Slice (D) and segmentation (E) of a relaxed plate forming a tube decorated with nucleosomes. Data information: Scale bars: 50 nm insets, B-E)
Figure 1A. Spike-binding antibodies in serum. Binding by antibodies of classes M, G, and A is detected with secondary antibodies conjugated to different fluorochromes, and the results are shown on the left, middle, and right plots, respectively. Binding (geometric mean fluorescence intensity - GMFI- of corresponding secondary antibody) to TE cells expressing SARS-CoV-2 spike protein is plotted on the vertical axis, and binding to untransfected cells on the horizontal axis. Each point represents a value from one donor. Samples from donors with no known exposure to SARS-CoV-2 antigens (n = 86) are plotted with blue circles, recently infected donors (n = 34) with red circles, and vaccinated donors (n = 14) with green diamonds. Red circles with black triangles correspond to donors from whose B cells monoclonal antibodies were isolated (n = 5, P values are derived from a two-way analysis of variance followed by Tukey's test to compare the specific binding, i.e., (binding to spike-expressing cells)/(binding to untransfected cells) between conditions (convalescent or vaccinated against unexposed) within each antibody class. The experiment was independently repeated three times, and results shown come from the third replicate.B. Change in antibody binding following vaccination against SARS-CoV-2. Binding of antibodies from sera assessed in the experiment shown in (A), is shown for two samples of serum from each of 7 donors. Data are plotted as in (A) with binding to spike-expressing cells on the vertical axis, and to untransfected cells on the horizontal, using blue symbols for samples from before vaccination, and red symbols for samples from 15-29 days after the first vaccination (but before any second vaccination). Black lines connect points corresponding to pre/post pairs of samples from each donor. Left plot shows results for IgM and right plot for IgG. C. Comparison of post-vaccination increase in binding to untransfected cells between IgG and IgM. The increase in binding to untransfected TE 0 cells between pre- and post-vaccination samples is shown on the left with blue symbols for IgG and on the right with black symbols for IgM. The horizontal line at y=0 is the expected result when no increased binding is observed. P value is derived from a two-tailed, Wilcoxon matched pairs signed rank test.D. Comparison of spike-specific IgM, as measured by flow cytometry or ELISA. The left two "FC" are the results of flow cytometry, and the left verical axis shows the ratio of serum IgM binding to spike-expressing cells, vs binding to non-expressing control cells, as plottted in A. The right two columns show spike-RBD-specific IgM as measured by an IgM-capture ELISA, and the right vertical axis shows the optical densities (OD). P values are calculated by two-way analysis of variance, followed by Sidak's multiple comparisons test. The entire experiment was repeated three times, and the data shown are derived from the third replicate.
Figure 4A. The effect of competition on concentration versus binding curves of three spike-specific, class-switched antibodies. Antibodies were expressed either as IgM, as originally isolated (black symbols and lines), or artificially switched to IgG1 (blue lines and symbols). For each antibody, identified by name at the top of each plot, the binding of the antibody alone ("alone", open symbols), or the competitive binding of the antibody in a mixture of IgM and IgG1 ("compet.", filled symbols) is shown. In the competition scenario, each of the two classes of the antibody were added together at the concentration shown on the horizontal axis. The vertical axis shows the ratio of geometric mean fluorescence of human IgM, or IgG on spike-expressing cells divided by the corresponding signal on spike-non-expressing control cells. Each point shows the mean of 3 values from three independent experiments. Error bars show standard error. P value was calculated by comparing the area under the curve of each antibody class in the "alone" condition with the binding of the "competition" condition by paired, two-tailed t-test.B. Virus neutralization by antibodies expressed as IgM or IgG1. A plaque reduction neutralization assay as described in Fig 3A-B was used to measure neutralization by the three, donor-derived IgM (black lines and open symbols) and their artificially class-switched IgG1 equivalents (blue lines and filled symbols). Horizontal axis shows the antibody concentration and the vertical axis shows the level of infection expressed as percentage GFP expression compared to control wells with no antibody added. Each point shows the mean of nine replicate values pooled from three independent experiments, each with triplicate wells. Error bars show standard error. C. Comparison of virus neutralization by antibodies expressed as IgM or IgG1 shown in B. Area under the curve was calculated from each of the three independently performed experiments. P was calculated by paired, two-tailed t-test.Virus neutralization by antibodies artificially class switched from IgA or IgG1 to IgM. A plaque reduction neutralization assay as described in Fig 3A-B was used to measure neutralization by the two donor-derived IgA (pink and light blue lines) and one donor-derived IgG (bordeaux lines). The antibodies expressed in their original classes (IgA or IgG) are plotted with filled symbols of the same colors as the lines, and their artificially class-switched IgM equivalents are plotted with open symbols. Horizontal axis shows the antibody concentration and the vertical axis shows the level of infection expressed as percentage GFP expression compared to control wells with no antibody added. Each point shows the mean of nine replicate values pooled from three independent experiments, each with triplicate wells. ND50 was calculated from each of the three independently performed experiments. P was calculated by paired, two-tailed t-test for each antibody pair.Affinities of donor-derived spike-binding IgG1 (n = 8) and donor-derived IgM (n = 3) expressed as IgG1, measured by surface plasmon resonance. P value was calculated by unpaired two-tailed t-test.
Figure 5A. Heatmap of antibody binding to spike protein subdomains (complete spike extracellular domain "spike", S1, S2, RBD and NTD in ELISA. Color gradient shown on right represents optical density at 450 nm (OD). Values are mean OD from two independent experiments. Analogous ELISA results for 3 IgM and their IgG1-class-switched derivativesC. Flow-cytometric epitope binning of monoclonal IgM, utilizing competitive displacement of IgG by IgM with identical variable region Cells expressing SARS-CoV-2 spike protein and untransfected control cells were incubated with each of 3 neutralizing IgM antibodies artificially switched to IgG1, either alone, or mixed with one of the 3 antibodies expressed as IgM. The binding of each IgG1 alone is shown in the last column of the heatmap, and in competition with each other IgM in columns 1-3. Color shade represents the specific IgG binding (ratio of GMFI on TE spike-mCherry cells to TE 0 cells). Values are mean GMFI ratios from three independent experiments. When IgM binds the same epitope as the IgG (automatically the case when the source antibody is the same), the IgM will displace the IgG, resulting in a reduction in the IgG signal. Asterisks mark those combinations of antibodies with a statistically significant decrease in binding of the IgG1 in the presence of IgM, compared to the IgG alone across 3 independent experiments, (* p<0.05, two-way analysis of variance, followed by Tukey's test).
Figure 1(D) Measurement of intracellular ROS levels by fluorescent probe DCFH-DA, and the fluorescence intensity of ROS was calculated; All scale bars are 20 μm. n=3 biological replicates.(G) Liver tissues were obtained from the indicated mice and then examined using transmission electron microscopy (Arrowheads indicate mitochondria); Scale bars are 1 μm and 5 μm. n = 3 biological replicates.
Figure 2(B) Gpx4 protein was measured in liver of WT and PPARα-/- mice fed blank solvent or GW7647; n = 4 biological replicates.(E) Chromatin immunoprecipitation assays were performed on soluble formaldehyde-crosslinked chromatin isolated from untreated and GW7647-treated WT or PPARα-/- livers with polyclonal anti-PPARα antibodies (anti-PPARα) or control IgG. The final DNA extraction was polymerase chain reaction-amplified with a primer pair that covered the sequence in intron 3 of Gpx4.
Figure 3(B) Liver sections were obtained from the indicated mice and stained with probe1. All scale bars are 20 μm. n = 3 biological replicates.(D) TRF protein was measured in liver of WT and PPARα-/- mice fed blank solvent or GW7647. n = 4 biological replicates.
Figure 4(E) Liver tissue was obtained from the indicated mice and then examined using transmission electron microscopy (Arrowheads indicate mitochondria). Scale bars are 1 μm and 5 μm. n = 4 biological replicates.(J) Measurement of intracellular ROS levels by fluorescent probe DCFH-DA, and the fluorescence intensity of ROS was calculated. All scale bars are 20 μm. n = 3 biological replicates.
Figure 5(E) Measurement of intracellular ROS levels by fluorescent probe DCFH-DA, and the fluorescence intensity of ROS was calculated. n = 3 biological replicates. All scale bars are 20 μm.(J) Measurement of intracellular ROS levels by fluorescent probe DCFH-DA, and the fluorescence intensity of ROS was calculated. n = 3 biological replicates. All scale bars are 20 μm.
Figure 1(D) HaloTag pulse-chase analysis in WT MEF monitoring fluorescent Halo-AATNNN during up to 6 h of chase in the presence of BafA1. The fluorescent JF646-Halo ligand and the polymer-specific 2C1 antibody stains are shown. (E) Same as (D) for fluorescent Halo-ATZNNN. (F) Quantification of accumulation of fluorescent Halo-AATNNN and Halo-ATZNNN within LAMP1-positive endolysosomes. Mean ± SEM, n=20, 11, 10, 13 for Halo-AATNNN, n= 18, 12, 12, 13 for Halo-ATZNNN. Two-way ANOVA and Sidak's multiple comparison test, ns P>0.05, *** P<0.001.
Figure 2A Confocal laser scanning microscopy analyses in cells treated with BafA1. Total HA-ATZNNN (red) or HA-ATZNNN polymers (magenta) in LAMP1-positive endolysosome (green) in WT MEF. (C) Same as (A) in Cnx-KO MEF. (D) Same as (A) in WT MEF exposed to kifunensine (KIF). (E) Same as (A) in WT MEF exposed to Castanospermine (CST). (F) Same as (A) in sCNX MEF. (G) Same as (A) in Uggt1-KO MEF. (J) Halo-ATZNNN in Uggt1-KO MEF mock-transfected (empty pcDNA3 plasmid). (K, L) (K) Same as (J), with a plasmid for expression of active or (L) inactive UGGT1. (M) Quantification of Halo-ATZNNN-positive endolysosomes (mean, n=22, 10, 15 cells for panels J-L, respectively). One-way ANOVA and Dunnett's multiple comparison test, ns P>0.05, **** P<0.0001).
Figure 3(B-I) Confocal laser scanning microscopy analyses (as in Fig. 2) in WT MEF treated with BafA1. (J, K) (J) Quantification of ATZxxx-positive endolysosomes and (K) of ATZxxx polymers-positive endolysosomes (mean, n= 18, 30, 24, 14, 27, 22, 27, 18 cells for HA stain and n= 12, 14, 14, 11, 14, 14, 17, 11 cells for 2C1 stain of panels B-I, respectively). One-way ANOVA and Dunnett's multiple comparison test, ns P>0.05, **** P<0.0001.
Figure 4(C) Co-immunoprecipitation of ATZXXX (Bait, lower panel) with CNX (upper panel) and BiP (middle panel). Protein content in the total cell extracts (TCE) is shown. (D) Quantification of (C) for CNX association (n=3). Unpaired two-tailed t-test, ** P<0.01*** P<0.001, **** P<0.0001. (E) Quantification of (C) for BiP association (n=3 for ATZNNN and ATZQQN; n=4 for ATZQNQ and ATZQQQ). Unpaired two-tailed t-test, * P<0.005, ** P<0.01, *** P<0.001, **** P<0.0001. (G) Confocal laser scanning microscopy in Flp-In 3T3 cells stably expressing ATZNNN in the absence of BafA1 (to allow clearance of misfolded model proteins delivered within endolysosomes). Co-localization with Calnexin (CNX). (H) Same as (G) for BiP co-localization. (I) Same as (G) for ATZQQQ. (J) Same as (H) for ATZQQQ. (K) HaloTag pulse-chase analysis in MEF monitoring fluorescent Halo-ATZNNN during up to 24 h. (L) Same as (K) for fluorescent Halo-ATZQQQ. Arrowheads show select clusters of JF646-labeled Halo-ATZQQQ. Arrowheads show co-localization Halo-ATZQQQ:BiP.
Figure 1The ERMIT assay relies on the signaling properties of IRE1, one of the three ER stress sensors and reports for a dimerization event occurring in the lumen of the ER. The assay can be applied to heterodimerization or homodimerization events. Western blot showing the expression of AGR2 dimers (D) and monomers (M) in HEK293T subjected to DSP-mediated cross-linking and that were previously transfected with either a control siRNA (siCTL) or a siRNA targeting AGR2 (siAGR2) for 24 h (C) Reduced or non-reduced samples were resolved by SDS-PAGE and immunoblotted using anti-AGR2, anti-ERK1 antibodies (for loading control).The ERMIT assay relies on the signaling properties of IRE1, one of the three ER stress sensors and reports for a dimerization event occurring in the lumen of the ER. The assay can be applied to heterodimerization or homodimerization events. Western blot showing the expression of AGR2 dimers (D) and monomers (M) in HEK293T subjected to DSP-mediated cross-linking and that were previously transfected with either a control siRNA (siCTL) or treated or not with tunicamycin (Tun) prior to cross-linking (D). Reduced or non-reduced samples were resolved by SDS-PAGE and immunoblotted using anti-AGR2 anti-calnexin (CANX) antibodies (for loading control).The ERMIT assay relies on the signaling properties of IRE1, one of the three ER stress sensors and reports for a dimerization event occurring in the lumen of the ER. The assay can be applied to heterodimerization or homodimerization events. F) AGR2 dimerization was monitored with ERMIT (wild-type (WT)). The luminescence signal was abrogated when using the kinase dead (KD) constructs and by the constructs exhibiting mutations in the dimerization domain (E60A or C81S or double mutant (DM)). The graph represents average signal normalized on reporter protein expression ± SD (n=5; **: WT/KD (p=0.002), E60/WT (p=0.0034), E60/KD (p=0.001), C81/KD (p=0.004), DM/WT (p=0.0021) and DM/KD (p=0.0017), respectively; *: C81/WT (p=0.0098)).The ERMIT assay relies on the signaling properties of IRE1, one of the three ER stress sensors and reports for a dimerization event occurring in the lumen of the ER. The assay can be applied to heterodimerization or homodimerization events. G) Cells expressing various bait and prey constructs and the XBP1 splicing reporter or the XBP1 splicing reporter alone were exposed to increasing concentrations of DTT. The ERMIT signals obtained with both baits were then normalized to that of XBP1s to obtain results independent of the activation of endogenous IRE1 by the use of chemical ER stressors (n = 4).
Figure 2B) Volcano plot representing the statistical analysis of the data from the screen, where the y axis represents statistical criteria and the x axis the fold change in luminescence units.
Figure 3A) Co-immunoprecipitation of AGR2 with TMED2 under basal and tunicamycin induced ER stress in intestinal epithelial cells treated in situ. *indicates Immunoglobulin heavy and light chains.C) Changes in AGR2 dimer and monomer ratio in TMED2 overexpressing cells. DSP-stabilized AGR2 was analyzed under non-reducing (top blot) or reducing conditions (bottom blot). D=dimeric, M=monomeric AGR2.E): Co-immunoprecipitation of AGR2 wild-type (WT, left panel) or AGR2 AA mutant (right panel) with TMED2 in HEK293T cells. Immunoprecipitation was performed with mouse anti-Flag antibody to pull-down the ectopic protein tag.F) Western blot analysis (left panel) and quantification (right panel) of AGR2 intracellular expression upon TMED2 overexpression. Data are representative of 4 independent experiments. Tubulin (TUB) was used as a loading control.G) HEK293T cells were transfected with control (ev) or TMED2 plasmid and then used in the ERMIT assay with AGR2 WT (n=3).H) Western blot analysis (left panel) and quantification (right panel) of AGR2 intracellular expression in total cell lysate (TCL) upon TMED2 silencing. Data are representative of 4 independent experiments. Tubulin (TUB) was used as a loading control.I) HEK293T cells were silencing for TMED2 and then used in the ERMIT assay with AGR2 WT (n=3).
Figure 4A) The ERMIT-based validation of the complex formation between AGR2 and LYPD3 or CD59, but not OS9. The monomeric AGR2 E60A was used as bait, while LYPD3, CD59 and OS9 were used as prays (n=6).B-C) Expression and subcellular localization of CD59-GFP WT and C94S.D and E) Co-immunoprecipitation of CD59-GFP WT or CD59 C94S mutant with AGR2 WT (D) or AGR2 AA mutant (E) in HEK293T cells.F-I) FACS analysis of CD59 WT (F and G) or CD59 C94S (H and I) total (F and H) and membrane (G and I) expression in HEK293T cells silenced for AGR2 (siAGR2) and TMED2 (siTMED2) when compared to control (siGL2) cells (F and H) or silenced for TMED2 (siTMED2) and overexpressing AGR2 WT or AGR2 AA mutant (G and I). Data are representative of three to four independent experiments. Membranous CD59 expression was detected with anti-GFP APC. ns: non-statistically significant; for F (*): p=0.0385, (***): p=0.0003 (left panel) and p=0.0002 (right panel), respectively; for G (*): p=0.0334, (**) p=0.0036 and (***) p=0.0003; for H (*): p=0.0171 and (**): p=0.0084; and for I (**) p=0.0086 (left panel) and p=0.0076 (right panel), respectively.
Figure 5A) Formation of GFP-LC3 autophagic puncta in TMED2 overexpressing HEK239T cells as monitored using confocal microscopy (right panel). DAPI was used for nuclear staining visualization. Percentage of GFP-LC3 puncta in control (CTL) and TMED2 overexpressing HEK293T cells as quantified from three independent experiments by counting 240 GFP-LC3 positive cells for each condition (left panel). (**): p=0.0032.B) Western blot detection (left panel) and quantification (right panel) of LC3 level in control and TMED2 overexpressing HEK293T cells treated or not with 50 µM chloroquine for 2 hours. Actin (ACT) served as a loading control. (*): p=0.0498.C) Western blot analysis of AGR2 expression in control and TMED2 overexpressing HEK293T cells upon autophagy inhibition with 20 µM and 10 µM chloroquine treatment. Actin (ACT) served as a loading control.D) HEK293T cells were transfected with control (ev) or TMED2 plasmid and then used in the ERMIT assay with AGR2 WT the presence of gradual amounts of chloroquine.E) Western blot analysis of secreted AGR2 upon TMED2 overexpression. eAGR2, extracellular AGR2; iAGE2, intracellular AGR2.F) Representative pictures of extracellular vesicles (EVs) heterogeneity purified from conditioned media of HEK293T cells transfected with control (ev) or TMED2 plasmid and analyzed by cryo-electron microscopy. Right upper panel: western blot analysis of CD63 in total medium (left) and in the purified extracellular vesicles fraction purified from media conditioned by control and TMED2 overexpressing cells (middle) and western blot analysis of AGR2 levels (right) in extracellular vesicles enriched from culture media conditioned by control and TMED2 overexpressing cells.G) Western blot analysis of secreted AGR2 upon TMED2 silencing eAGR2, extracellular AGR2; iAGE2, intracellular AGR2. H) Quantification of extracellular AGR2 level (eAGR2) in cells silenced for TMED2 (siTMED2), compared to control (siGL2). Data are representative of three independent experiments and are presented as extracellular-to-intracellular AGR2 ratio. (**): p=0.0029.I) Secretion of AGR2 wild-type (wt), E60A and ∆45 mutant as determined by Western blot. eAGR2, extracellular AGR2; iAGE2, intracellular AGR2.
Figure 6A) Representative histological H&E staining of sections of the proximal colon and ileum of WT and TMED2 hypomorph mice.B) Immunohistological analysis of AGR2 and MUC2 expression in the proximal colon of WT and TMED2 hypomorph mice.C) Semi-quantitative analysis of AGR2 and MUC2 expression in the proximal colon of WT (blank bars) and TMED2 hypomorph mice (black bars) (n=6).D) Freshly isolated PBMCs were placed in Boyden chambers towards media conditioned by cells overexpressing AGR2 WT, E60A, ∆45 or AGR2 AA mutants and incubated for 24 h. Migrating cells were then characterized and quantified by flow cytometry using FCS/SSC parameters or CD14 monocyte marker. (**): p=0.0016.E and F) Freshly isolated PBMC were placed in Boyden chambers towards media conditioned by cells overexpressing TMED2 and either AGR2 WT (E) or AGR2 AA mutant (F) and incubated for 24 h. Migrating cells were then characterized and quantified For E (*): p=0.0461 (AGR2WT/TMED2) and 0.018 (AGR2WT/TMED2 + blocking Ab) respectively; (**): p=0.0053 and (***): p=0.0048; for F (***): p=0.0007.G) Freshly isolated PBMC were placed in Boyden chambers towards media conditioned by cells silenced for TMED2 and incubated for 24 h. Migrating cells were then characterized and quantified (*): p=0.0149.H) Freshly isolated PBMC were placed in Boyden chambers towards decreased doses of recombinant AGR2 and incubated for 24 h. CCL2 cytokine was used as positive control for monocyte migration. ns: non-statistically significant, (*): p=0.0171, (**): p=0.0084, (***): p=0.0003.I) Impact of AGR2 blocking antibodies on AGR2-mediated monocytes migration was tested using Boyden chambers as described above. The concentrations of recombinant human AGR2 was of 200 ng/ml and decreasing amounts of antibodies were used from 20 µg to 1 µg. The non-relevant antibody (Isotype) was used at the maximal dose of 20 µg. Data are representative of three independent experiments. ns: non-statistically significant, (*): p=0.0165 (Ab=20μg/ml), 0.0223 (Ab=10μg/ml) and 0.0493 (Ab=5μg/ml), respectively.
Figure 7A) Selective enrichment of AGR2 modulators in colonic Crohn's disease (CD). Percentage of tested genes with altered expression in colonic biopsies from patients with Ulcerative Colitis (UC, n=8) and colonic CD (CC, n=15) and in ileal biopsies from patients with ileo-colonic CD (IC, n=9).B) Hierarchical clustering of the AGR2 modulator genes significantly deregulated in non-inflamed colonic mucosa from patients with Crohn's Disease (CD) versus healthy controls (C) (dChip software t-Test)C) TMED2 mRNA expression in healthy controls (CT), colonic Crohn's disease (CC) and ulcerative colitis (UC).D) Representative immunohistological analysis of TMED2 in non-inflamed colonic biopsies from healthy controls and patients with active CD.E) Representative immunohistological analysis of CD163 (scavenger receptor present in macrophages), AGR2, and TMED2 in non-inflamed colonic biopsies from healthy controls and patients with active or quiescent CD.F) Semi-quantitative analysis of CD163, AGR2, and TMED2 immunostaining in colonic mucosa from healthy controls (C) and patients with quiescent (Q) or active (A) CD. Three random sections from each patient of the four groups were scored. Final IHC scores (AxB range to 0-9) combine the percentage of positively labelled cells. A: % of IHC positive labeled cells - 0 (0%), 1 (<30%), 2 (30 to 60%), 3 (>60%)) and the intensity of the reaction product. B: 0 (no reaction), 1 (weak), 2 (mild), 3 (strong) in most of the examined fields. All values are mean ± S.E.M.