Journal: Bioactive Materials

Article Title: Apolipoprotein E knockout attenuates vascular graft fibrosis by reducing profibrotic macrophage formation through low-density lipoprotein receptor related protein 1

doi: 10.1016/j.bioactmat.2026.01.029

Figure Lengend Snippet: Profibrotic macrophages increasing fibroblast proliferation via their secreted IGF-1. (a) Dot plots of Igf1 expression in C2 and the other subgroups of macrophages in regenerated aortas 30 and 90 days after graft implantation in WT and Apoe −/− rats. (b) Igf1 expression score in macrophages in regenerated aortas 30 and 90 days after graft implantation in WT and Apoe −/− rats. ∗∗∗∗ indicates p < 0.0001, unpaired t -test. (c) Quantification of IGF-1 concentration in regenerated aortas 30 and 90 days after graft implantation in WT and Apoe −/− rats. ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each time point and each group, five different samples from five different animals were analyzed (n = 5). UMAP of fibroblasts in regenerated aortas 30 days (d) and 90 days (e) after graft implantation in WT and Apoe −/− rats, heatmap of cell cycle (Ccnd1, Ccnd2, and Ccnd3) scores in UMAP of fibroblasts, and box plots of cell cycle scores in fibroblasts. ∗∗∗∗ indicates p < 0.0001, unpaired t -test. (f) Immunofluorescence staining of Ki67 in regenerated aortas 30 and 90 days after graft implantation in WT and Apoe −/− rats. L indicates lumens. (g) Quantification of Ki67 positive cells in regenerated aortas. ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each time point and each group, five different images from five different animals were analyzed (n = 5). (h) Quantification of IGF-1 in culture mediums of WT and APOE KO macrophages after their culture on PCL scaffolds for 48 h by ELISA. ∗∗ indicates p < 0.01, unpaired t -test. For each group, three different samples were analyzed (n = 3). (i) Immunofluorescence staining of Ki67 in WT and APOE KO fibroblasts after treatment with IGF-1 (10 ng/mL) for 24 h. Cells were counterstained with phalloidin. (j) Quantification of proliferation of WT and APOE KO fibroblasts treated with IGF-1 (10 ng/mL) for 24 h using cell counting kit-8 (CCK-8). ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each group, three different samples were analyzed (n = 3). (k) Quantification of proliferation of WT fibroblasts treated with conditioned medium (CM) with or without IGF-1 blocking antibody (Ab, 1 μg/mL) for 24 h using CCK-8. CM were medium conditioned by WT macrophages cultured on PCL scaffolds for 48 h ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each group, three different samples were analyzed (n = 3).

Article Snippet: Exogenous APOE (0.25 μg/mL, MCE, HY-P701096), TGF-β1 (10 ng/mL, MCE, HY-P7117), IGF-1 (10 ng/mL, MCE), conditioned medium by macrophages, or IGF-1 blocking antibody (1 μg/mL, Invitrogen, MA5-18035) was added into culture medium and incubated with WT or APOE KO fibroblasts for 24 h.

Techniques: Expressing, Concentration Assay, Immunofluorescence, Staining, Enzyme-linked Immunosorbent Assay, Cell Counting, CCK-8 Assay, Blocking Assay, Cell Culture

Journal: Bioactive Materials

Article Title: Apolipoprotein E knockout attenuates vascular graft fibrosis by reducing profibrotic macrophage formation through low-density lipoprotein receptor related protein 1

doi: 10.1016/j.bioactmat.2026.01.029

Figure Lengend Snippet: Downregulation of APOE by AAV ameliorating fibrosis during vascular regeneration after graft implantation in vivo . (a) Illustration of a strategy of adventitial delivery of AAV-shRNA(Apoe) to inhibit APOE levels in regenerated aortas after graft implantation in vivo . Two weeks after graft implantation in vivo , AAV-shRNA(Apoe) were injected into the adventitia of the regenerated aortas, which were then harvested for analysis three weeks later. (b) M mode images of ultrasound detection of regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks. Arrow heads indicate movement of vascular walls. (c) Tensile tests of regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks. (d) Quantification of RI, PI, and compliance of regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks. ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each group, six different images from six different animals were analyzed (n = 6). (e) Quantification of elastic modulus of regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks. ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each group, six different images from six different animals were analyzed (n = 6). (f) H&E, MTC and EVG staining of regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks. (g) Immunofluorescence staining of COL I, COL III, elastin, αSMA, and eNOS in regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks. L indicates lumens. Arrow heads indicate capillaries. Quantification of adventitia thickness (h), collagen positive areas according to MTC staining (i), elastin positive areas according to EVG staining (j), COL I positive areas (k), COL III positive areas (l), and number of capillaries (m) in adventitial areas of regenerated aortas. (n) Immunofluorescence staining of CTSD and CD68 in regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks. (o) CD68 and CTSD double positive cells in regenerated aortas. ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each group, six different samples from six different animals were analyzed (n = 6). (p) WB results of APOE, CTSD and SPP1 levels in regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks and quantification of levels of APOE, CTSD and SPP1 in regenerated aortas. ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each group, six different samples from six different animals were analyzed (n = 6). (q) Quantification of IGF-1 concentrations in regenerated aortas treated with PBS, AAV-shRNA(NC), and AAV-shRNA(Apoe) for 3 weeks by ELISA. ∗∗ indicates p < 0.01, Tukey's post-hoc test. For each group, six different samples from six different animals were analyzed (n = 3).

Article Snippet: Exogenous APOE (0.25 μg/mL, MCE, HY-P701096), TGF-β1 (10 ng/mL, MCE, HY-P7117), IGF-1 (10 ng/mL, MCE), conditioned medium by macrophages, or IGF-1 blocking antibody (1 μg/mL, Invitrogen, MA5-18035) was added into culture medium and incubated with WT or APOE KO fibroblasts for 24 h.

Techniques: In Vivo, shRNA, Injection, Staining, Immunofluorescence, Enzyme-linked Immunosorbent Assay

Journal: npj Imaging

Article Title: Development and validation of an activatable PET radiotracer reporting extracellular myeloperoxidase activity for the detection of unstable atherosclerotic plaque

doi: 10.1038/s44303-026-00156-9

Figure Lengend Snippet: a , b Blood kinetics of [ 68 Ga]Ga-IEMA up to 90 min after intravenous administration of the radiotracer (102.6 ± 1.5 µL, 8.2 ± 3.8 MBq) into Apoe –/– mice without (non-TS Apoe –/– , n = 6) and with Tandem Stenosis (TS) surgery (TS Apoe –/– , n = 8) as measured by in vivo positron emission tomography (PET) imaging of the left ventricle. Image analysis using an exponential two-phase decay model shows that [ 68 Ga]Ga-IEMA was eliminated from the blood in a biexponential manner typical of radiotracers with extracellular distribution and renal clearance, as indicated in ( b ). c Reversed-phase HPLC of urine directly after collection from non-TS Apoe –/– ( n = 3) and TS Apoe –/– ( n = 4) mice 90 min after administration of [ 68 Ga]Ga-IEMA (104.8 ± 3.8 µL, 11.4 ± 2.6 MBq) showing intact radiotracer at 10.8 min and the formation of a new compound eluting at 10.0 min. Representative chromatograms for urine obtained from non-TS Apoe –/– and TS Apoe –/– mice are shown. d Percentage of total signal (peaks at 10.8 and 10.0 min) present in the peak at 10.0 min. * P < 0.05 (Mann–Whitney test).

Article Snippet: Male apolipoprotein E gene-deficient ( Apoe –/– ) mice purchased originally from Charles Rivers Laboratories (Edinburgh, UK) were housed and bred in the Biological Service Facility at King’s College London.

Techniques: In Vivo, Positron Emission Tomography, Imaging, MANN-WHITNEY

Journal: npj Imaging

Article Title: Development and validation of an activatable PET radiotracer reporting extracellular myeloperoxidase activity for the detection of unstable atherosclerotic plaque

doi: 10.1038/s44303-026-00156-9

Figure Lengend Snippet: a Representative in situ images after dissection show (i) the presence of atherosclerotic lesions in the brachiocephalic artery (BCA) known to contain stable lesions in both Apoe –/– mice without (non-TS) and with Tandem Stenosis (TS); (ii) the selective presence of atherosclerotic lesions known to have characteristics of unstable plaque in Segment I (Seg I) of TS but not the corresponding lesion-free anatomical location in non-TS mice (white arrow); and (iii) the lesion-free left carotid artery (LCA) (scale bar = 0.5 mm). b Representative whole-body coronal images of in vivo PET imaging with [ 68 Ga]Ga-IEMA in non-TS ( n = 6) and TS Apoe –/– mice ( n = 8) 50–60 min after administration of the radiotracer (102.6 ± 1.5 µL, 8.2 ± 3.8 MBq). c Transverse images at the level of Seg I and contralateral LCA show increased retention of [ 68 Ga]Ga-IEMA in Seg I compared with the anatomical location corresponding to Seg I in control non-TS Apoe –/– mice, where plaque is absent (white arrow) (scale bar = 2 cm). d Zoomed images taken at the level of Seg I and the BCA from three different mice per group showing increased signal due to increased retention of [ 68 Ga]Ga-IEMA in Seg I (yellow box) compared with the BCA in TS Apoe –/– mice (green box). The images also confirm a lack of retention [ 68 Ga]Ga-IEMA in the site corresponding to Seg I in non-TS Apoe –/– mice (broken yellow box) (scale bar = 0.5 mm). e Maximum standardized uptake value (SUV max ) of Seg I and BCA obtained from in vivo PET images 50–60 min post-injection of [ 68 Ga]Ga-IEMA in non-TS Apoe –/– (open squares) and TS Apoe –/– mice (filled circles). * P < 0.05 (ANOVA with a Tukey post hoc test). T trachea.

Article Snippet: Male apolipoprotein E gene-deficient ( Apoe –/– ) mice purchased originally from Charles Rivers Laboratories (Edinburgh, UK) were housed and bred in the Biological Service Facility at King’s College London.

Techniques: In Situ, Dissection, In Vivo, Imaging, Control, Injection