Journal: Frontiers in Immunology

Article Title: Mouse TAPBPR shows functional similarity to human TAPBPR in shaping the MHC-I immunopeptidome

doi: 10.3389/fimmu.2026.1756668

Figure Lengend Snippet: Feature of mouse TAPBPR protein. (A) ClustalWS alignment comparison between mouse TAPBPR (mouse TAPBPR, UniProt Q8VD31 ) and human TAPBPR (UniProt Q9BX59 ) proteins. Blosum62 scoring system was generated by Jalview 2.11.4.0 software. Boxes highlight the peptide editing loop (blue), MHC-I binding sites characterized as TN5, TN6, TC2 and TC3 (red), the free cysteine residue (black), two predicted N-linked glycosylation sites in mouse TAPBPR (purple, with the asparagine indicated by an asterisk) and the cytoplasmic tail regions (yellow). The endogenous mouse TAPBPR sequence in MC-38, B16-F10, and MEF-BL/6–1 cells was confirmed as equivalent to the UniProt reference. (B) Predicted AlphaFold2 structure of mouse TAPBPR (green) bound to H2-D b (blue) with N-linked glycosylations (pink) modelled using GLYCAM ( https://glycam.org ). For H2-D b , only two of the three glycans are visible in the image, with N86 obscured by the orientation depicted. (C) Representative histograms and bar graphs showing mean fluorescence intensity (MFI) of intracellular TAPBPR expression, detected using AnDi3 antibody, on IFNγ-treated wildtype (WT) MC-38, B16-F10, and MEF-BL/6–1 cells compared to TAPBPR knockout (KO) and mouse TAPBPR overexpressed (OE) equivalents, which serve as negative and positive controls, respectively. Error bars show MFI -/+ standard error of mean (SEM) from three independent experiments. *p ≤ 0.05, **p ≤ 0.01 using unpaired t-test. (D) Histograms showing IFNγ inducibility of intracellular TAPBPR expression in WT MC-38 and B16-F10 cells and in cells transduced to overexpress (OE) mouse TAPBPR.

Article Snippet: Murine colon adenocarcinoma MC-38 (Kerfast, Newark, CA 94560, USA), mouse melanoma B16-F10, Lewis lung carcinoma LL/2 and mouse stromal fibroblast MEF-BL/6-1 (ATCC SCRC-1008) cells were maintained in Dulbecco’s Modified Eagle’s medium (DMEM)(CAT: 41966052, GibcoTM, Thermo Fisher Scientific, Paisley, Renfrewshire, UK), supplemented with 10% fetal bovine serum (FBS)(CAT: 10500064, GibcoTM) and 100 units/mL penicillin-streptomycin (CAT: 15140122, GibcoTM) at 37 °C, 5% CO 2 , and humid atmosphere.

Techniques: Comparison, Generated, Software, Binding Assay, Residue, Glycoproteomics, Sequencing, Fluorescence, Expressing, Knock-Out

Journal: Frontiers in Immunology

Article Title: Mouse TAPBPR shows functional similarity to human TAPBPR in shaping the MHC-I immunopeptidome

doi: 10.3389/fimmu.2026.1756668

Figure Lengend Snippet: Mouse TAPBPR interaction partners identified in B16-F10, MC-38 and MEF-BL/6–1 cell lines. Mouse TAPBPR was isolated by immunoprecipitation, using Andi38 antibody, from TAPBPR knockout (KO) or mouse TAPBPR overexpressing (OE) from (A) B16-F10 cells, (B) MC-38 cells, (C) MEF-BL/6–1 cells or (D) MC-38 cells with β2m knocked out. Scatterplots show all proteins identified via mass spectrometry in the mouse TAPBPR pull-downs in cells overexpressing mouse TAPBPR compared to the equivalent TAPBPR KO cell line. Selected significant interaction partners highlighted are TAPBPR (pink), H2-D b (red), H2-K b (yellow), MHC-I (orange), which covers peptides common to H2 molecules and therefore cannot be assigned to a specific MHC-I molecule, β2m (navy) and known components of the MHC-I antigen presentation pathway (purple). (E) Confirmation of mouse TAPBPR binding partners at endogenous TAPBPR levels in MC-38 cells. Immunoblots indicating abundance of mouse TAPBPR (mTAPBPR), MHC-I, β2m, calnexin, tapasin, TAP2, and GAPDH (loading control) in the whole cell lysates and mouse TAPBPR immunoprecipitates (IP: mTAPBPR) from WT MC-38 cells. MC-38 with TAPBPR knocked out (KO) or overexpressing mouse TAPBPR (OE) are included as controls. Cells competent for β2m expression or with β2m knocked down (β2m KD) were compared to assess the importance of the TAPBPR/MHC-I interaction in the observed associations. An antibody-only lane is included to highlight the antibody’s heavy chain used in the immunoprecipitation. N = 1, for tapasin and TAP2 blot. (F) Endogenously expressed mouse TAPBPR exhibits a prolonged association with H2-D b compared to H2-K b in both MC-38 and B16 cells. Immunoblots indicating abundance of mTAPBPR, MHC-I, β2m, calnexin, and GAPDH (loading control) in the whole cell lysate and mTAPBPR immunoprecipitated fraction (IP: mTAPBPR) with Andi 38 from MC-38 or B16-F10 WT cells, and variant cell lines expressing H2-D b only (H2-K b knockout), H-2K b only (H2-D b knockout) or lacking efficient expression of both H2-D d and -K b following β2m knock down (KD). Representative of three independent experiments. Note: Arrowheads indicate the positioning of the major TAPBPR and MHC-I bands in the gels, where background bands were present in the immunoprecipitations. The position of TAPBPR relative to the antibody control also varies due to minor changes in running conditions between experiments. Note: WT cells in F were treated with a non-targeting RNA guide in the RNP.

Article Snippet: Murine colon adenocarcinoma MC-38 (Kerfast, Newark, CA 94560, USA), mouse melanoma B16-F10, Lewis lung carcinoma LL/2 and mouse stromal fibroblast MEF-BL/6-1 (ATCC SCRC-1008) cells were maintained in Dulbecco’s Modified Eagle’s medium (DMEM)(CAT: 41966052, GibcoTM, Thermo Fisher Scientific, Paisley, Renfrewshire, UK), supplemented with 10% fetal bovine serum (FBS)(CAT: 10500064, GibcoTM) and 100 units/mL penicillin-streptomycin (CAT: 15140122, GibcoTM) at 37 °C, 5% CO 2 , and humid atmosphere.

Techniques: Isolation, Immunoprecipitation, Knock-Out, Mass Spectrometry, Immunopeptidomics, Binding Assay, Western Blot, Control, Expressing, Variant Assay, Knockdown

Journal: eBioMedicine

Article Title: A next-generation probiotic strain for gut health: Bacteroides cellulosilyticus LYH2 variant with anti-inflammatory and metabolic advantages

doi: 10.1016/j.ebiom.2026.106232

Figure Lengend Snippet: Effects of B . cellulosilyticus LYH2 and comparator treatments on disease severity, inflammation, and goblet cell number in a DSS-induced colitis mouse model. Six-week-old male C57BL/6J mice were randomly assigned to six groups (n = 7): CON (normal drinking water), DSS (3% DSS in drinking water), Ce (3% DSS and B . cellulosilyticus LYH2 at 1 × 10 9 CFU/mL), JCM (3% DSS and B . cellulosilyticus JCM 15632 at 1 × 10 9 CFU/mL), 5-ASA (3% DSS and 5-aminosalicylic acid at 100 mg/kg), and LR (3% DSS and Lactobacillus reuteri ATCC BAA-2837 at 1 × 10 9 CFU/mL). Bacterial strains and 5-ASA were given by oral gavage every other day for 21 days before DSS exposure. Colitis was then induced with 3% DSS for 8 days, during which bacterial treatments were paused while 5-ASA continued. (A) Body weight ratio during the experiment. (B) Final body weight. (C) DAI scores during DSS treatment. (D) Representative images of colons from each group. (E) Colon length. (F) Serum monocyte chemoattractant protein-1 (MCP-1) levels. (G) Serum interleukin-1β (IL-1β) levels. (H) Serum tumour necrosis factor-α (TNF-α) levels. (I) Serum interleukin-10 (IL-10) levels. (J) Representative H&E-stained colon sections. Scale bars = 200 μm, 10× objective. (K) Histological scores of colonic tissues. (L) Representative AB-PAS-stained colon sections. Scale bars = 200 μm, 10× objective. (M) Goblet cell number per crypt. (N) Relative mRNA expression of inflammatory and chemokine-related genes ( Tnf , Il1b , Mcp1 , and Cxcl10 ) in colon. Data are mean ± SEM (n = 7). Statistical significance was evaluated using either one-way ANOVA followed by Dunnett's post-hoc test (when normality and homogeneity of variance were met) or the Kruskal–Wallis test followed by Dunn's post-hoc test with Bonferroni correction (when these assumptions were violated), for comparisons of each group versus the DSS group. ∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗ P < 0.001.

Article Snippet: Effects of B . cellulosilyticus LYH2 and comparator treatments on disease severity, inflammation, and goblet cell number in a DSS-induced colitis mouse model. Six-week-old male C57BL/6J mice were randomly assigned to six groups (n = 7): CON (normal drinking water), DSS (3% DSS in drinking water), Ce (3% DSS and B . cellulosilyticus LYH2 at 1 × 10 9 CFU/mL), JCM (3% DSS and B . cellulosilyticus JCM 15632 at 1 × 10 9 CFU/mL), 5-ASA (3% DSS and 5-aminosalicylic acid at 100 mg/kg), and LR (3% DSS and Lactobacillus reuteri ATCC BAA-2837 at 1 × 10 9 CFU/mL).

Techniques: Staining, Expressing

Journal: eBioMedicine

Article Title: A next-generation probiotic strain for gut health: Bacteroides cellulosilyticus LYH2 variant with anti-inflammatory and metabolic advantages

doi: 10.1016/j.ebiom.2026.106232

Figure Lengend Snippet: Assessment of pig-derived B. cellulosilyticus LYH2 live bacteria and metabolites on growth performance, colon length, morphology, physical and chemical barriers, and spleen index in a DSS-induced colitis mouse model. Sixty 6-week-old male C57BL/6J mice were randomly divided into four groups (n = 10): CON (normal drinking water), DSS (3% DSS in drinking water), Ce (3% DSS and B. cellulosilyticus LYH2 at 10 9 CFU/mL), and Ce-M (3% DSS and B. cellulosilyticus LYH2-derived metabolites). B. cellulosilyticus LYH2 and its metabolites were orally administered every other day for 21 days before DSS induction, whereas control mice received an equal volume of PBS. All treatments were suspended during the DSS challenge period (7 days). (A) Changes in body weight of mice during DSS processing (n = 10). (B) Changes in Disease Activity Index (DAI) scores of mice during DSS processing (n = 10). (C) Representative images of caecum and colon from mouse in each group. (D) Comparison of colon length among different groups of mice (n = 10). (E) Representative images of colonic morphology from each group (HE staining). The images in the upper row were acquired using a 4× objective (scale bars: 100 μm), while those in the lower row were acquired using a 10× objective (scale bars: 100 μm). (F) Illustrative images depicting the thickness of the colonic mucus layer across different groups. Images were stained with Alcian Blue (AB) and nuclear fast red, and acquired using a 20× objective. Scale bars: 50 μm. (G) Histopathological status of colonic tissues from various groups (n = 10). (H) Thickness of colonic mucus layer across groups (n = 10). (I) Spleen index (spleen weight/body weight) across groups (n = 10). (J–M) Relative mRNA expression levels of Mucin 2 and tight junction proteins occludin, ZO-1, and claudin-1 in colonic tissues across groups (n = 10). (N) Immunofluorescence staining of ZO-1 protein (red) in colonic tissues, with nuclei counterstained by DAPI (blue). Scale bars: 50 μm. (O–Q) Quantification of the median fluorescence intensity (MFI) of tight junction proteins, occludin, ZO-1 and claudin-1 in colonic tissues (n = 3). MFI values were normalised to the mean value of the control group and presented as fold increase. Statistical significance was determined using one-way ANOVA with Tukey's post-hoc multiple-comparison tests. ∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗ P < 0.001.

Article Snippet: Effects of B . cellulosilyticus LYH2 and comparator treatments on disease severity, inflammation, and goblet cell number in a DSS-induced colitis mouse model. Six-week-old male C57BL/6J mice were randomly assigned to six groups (n = 7): CON (normal drinking water), DSS (3% DSS in drinking water), Ce (3% DSS and B . cellulosilyticus LYH2 at 1 × 10 9 CFU/mL), JCM (3% DSS and B . cellulosilyticus JCM 15632 at 1 × 10 9 CFU/mL), 5-ASA (3% DSS and 5-aminosalicylic acid at 100 mg/kg), and LR (3% DSS and Lactobacillus reuteri ATCC BAA-2837 at 1 × 10 9 CFU/mL).

Techniques: Derivative Assay, Bacteria, Control, Activity Assay, Comparison, Staining, Expressing, Immunofluorescence, Fluorescence

Journal: eBioMedicine

Article Title: A next-generation probiotic strain for gut health: Bacteroides cellulosilyticus LYH2 variant with anti-inflammatory and metabolic advantages

doi: 10.1016/j.ebiom.2026.106232

Figure Lengend Snippet: Ffar3 mediates the immunomodulatory effects of B. cellulosilyticus LYH2 and sodium propionate on T-cell homoeostasis, inflammatory responses, and macrophage activation in DSS-induced colitis. (A) Representative flow cytometry plots of peripheral CD3 + T cells gated for CD4 + and CD8 + subsets in WT and Ffar3 −/− mice under CON, DSS, Ce, and NaP conditions. (B) Quantification of circulating T-cell subsets: CD3 + CD8 + , CD3 + CD4 + CD8 - , CD3 + CD4 − CD8 + , and CD3 + CD4 − CD8 - (n = 5). (C) Serum levels of MCP-1, TNF-α, and IL-1β measured by ELISA (n = 5). (D) Relative Ffar3 mRNA expression in colonic mucosa of WT mice by qPCR (n = 5). (E) Relative mRNA expression of M1 macrophage-associated and antigen-presentation genes ( Il1b , Nos2 , Tnf , and Cd86 ) in colonic mucosa of WT and Ffar3 −/− mice (n = 5). (F) Representative immunofluorescence images of CD86 (red) in colon tissue. Nuclei were counterstained with DAPI (blue). Scale bars = 20 μm. (G) Quantification of CD86-positive area fraction in colon (n = 3). Data are mean ± SEM. Statistical significance was analysed by two-way ANOVA considering treatment (T), genotype (KO), and their interaction (T & KO). ∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗ P < 0.001.

Article Snippet: Effects of B . cellulosilyticus LYH2 and comparator treatments on disease severity, inflammation, and goblet cell number in a DSS-induced colitis mouse model. Six-week-old male C57BL/6J mice were randomly assigned to six groups (n = 7): CON (normal drinking water), DSS (3% DSS in drinking water), Ce (3% DSS and B . cellulosilyticus LYH2 at 1 × 10 9 CFU/mL), JCM (3% DSS and B . cellulosilyticus JCM 15632 at 1 × 10 9 CFU/mL), 5-ASA (3% DSS and 5-aminosalicylic acid at 100 mg/kg), and LR (3% DSS and Lactobacillus reuteri ATCC BAA-2837 at 1 × 10 9 CFU/mL).

Techniques: Activation Assay, Flow Cytometry, Enzyme-linked Immunosorbent Assay, Expressing, Immunopeptidomics, Immunofluorescence