Journal: Bioactive Materials

Article Title: Targeting VEGFR2 inhibition within a spatially-confined conduit promotes nerve self-resolution and alleviates mechanical allodynia

doi: 10.1016/j.bioactmat.2026.03.009

Figure Lengend Snippet: Prevention of neuroma formation by a spatially confined conduit filled with GelMA MAVP MPS. ( A ) Illustration of 3D-printed GelMA MPs loaded with MAVP and the proposed mechanism of action within the neural conduit. ( B ) Representative images and ( C ) quantitative scores of autotomy behavior over 12 weeks (n = 6). ( D ) Representative gait footprints at 12 weeks post-surgery. ( E ) Quantification of left hindlimb stance duration (n = 6) and ( F ) maximum contact area (n = 6). ( G ) IF staining of p-VEGFR2 activation and ( H ) IF staining of neovascularization marker RECA-1. (I) Quantification of p-VEGFR2-positive area percentage (n = 6). and ( J ) quantification of RECA-1-positive area percentage (n = 6). ( K ) Regenerated nerve length measurements (n = 6). Mean values are shown and error bars represent ± s.d., as analyzed by one-way ANOVA followed by the Tukey-Kramer test in ( C , E , F , I , J and K ). Biological replicates were used for all experiments. ns, p > 0.05, ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001, ∗∗∗∗p < 0.0001.

Article Snippet: The following primary antibodies were used for the subsequent steps: anti-Yap (mouse, 1:200, Santa sc-376830); anti-p-VEGFR2 (rabbit, 1:100 Invitrogen, PA5-105765); α-SMA (rabbit, 1:200, Proteintech 14395-1-AP); Reca-1 (mouse, 1:200, Santa sc-52665); anti-CD31 (mouse, 1:200, Santa sc-13537); anti-Ki67 (rabbit, 1:150, Cell Signaling 9129S); anti-NF-200 (mouse, 1:200, Sigma, SAB4200747); anti-MBP (rabbit, 1:200, Abcam ab218011); anti-F4/80 (mouse, 1:200, Santa sc-377009); Iba-1 (rabbit, 1:150, Abcam ab178846); anti-CGRP (rabbit, 1:400, Abcam ab283568); anti-TRPA1 (mouse, 1:200, Santa sc-376495); anti-CD86 (rabbit, 1:200, Proteintech 30691-1-AP); CD206 (rabbit, 1:200, Proteintech 18704-1-AP).

Techniques: Staining, Activation Assay, Marker

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: The schematic illustrates the nebulized inhalation of an integrated nanovesicle system (Res-PD-L1@nmEVs) alleviated inflammation, oxidative stress injury, neutrophil activation, and promote mitochondrial integrity to mitigate lung ischemia-reperfusion injury and MRSA-induced bacterial pneumonia.

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: Activation Assay

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: Characterization of Res-PD-L1@nmEVs . (A) Schematic illustration of the Res-PD-L1@nmEVs synthesis procedure. (B-D) Representative transmission electron microscopy (TEM) images, dynamic light scattering (DLS) size distributions, and zeta potential measurements of nEVs, PD-L1@mEVs, PD-L1@nmEVs, and Res-PD-L1@nmEVs. (E) PD-L1 expression in PD-L1-overexpressing MSCs (OE-PD-L1) and negative control (NC) MSCs, and CD11b expression in HL60 cells before and after DMSO stimulation, as determined by Western blot. (F) Expression levels of neutrophil membrane markers (CD11b, CXCR2, RAGE, TLR2) and the exosomal marker CD63 in the four EV types. (G) Fluorescence co-localization images of DiO-labeled nEVs (green) and DiL-labeled PD-L1@mEVs (red) after fusion, demonstrating hybrid vesicle formation. (H) Size stability of Res-PD-L1@nmEVs stored at 4 °C and 37 °C for 7 days. (I-K) Binding and neutralization capacity of Res-PD-L1@nmEVs against inflammatory cytokines (TNF-α, IL-6, IL-1β) in vitro. ∗ vs. 0ug/ml; # vs. 100 μg/ml, p < 0.05, n = 5.

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: Transmission Assay, Electron Microscopy, Zeta Potential Analyzer, Expressing, Negative Control, Western Blot, Membrane, Marker, Fluorescence, Labeling, Binding Assay, Neutralization, In Vitro

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: Res-PD-L1@nmEVs Attenuate Inflammation and Oxidative Damage in Lung Epithelial Cells In Vitro . (A-B) Flow cytometric analysis and quantification (B) of DiO-labeled Res-PD-L1@nmEVs uptake by BEAS-2B cells under H/R conditions after pretreatment with different endocytic inhibitors (chlorpromazine, chloroquine, and filipin) or incubation at 4 °C. (C) mRNA expression levels of IL-6, TNF-α, and IL-1β in BEAS-2B cells with or without H/R injury following pretreatment with Res, nEVs, PD-L1@mEVs, PD-L1@nmEVs, or Res-PD-L1@nmEVs. (D-E) Representative fluorescence images (D) and quantitative analysis (E) of cell proliferation assessed by BrdU incorporation (red; nuclei stained with DAPI, blue). Scale bar: 50 μm. (F-G) Apoptosis rates detected by flow cytometry (F) and flow cytometric analysis of Annexin V-positive BEAS-2B cells under the indicated conditions (G). (H–K) Fluorescence microscopy images and quantitative analysis of intracellular nitric oxide (NO, green) (H-I) and reactive oxygen species (ROS, red) (J-K). Scale bar: 100 μm. (L) Flow cytometry analysis of intracellular ROS levels. (M − O) Levels of malondialdehyde (MDA) (M), superoxide dismutase 2 (SOD2) activity (N), and glutathione (GSH) content (O) in cells. (P-Q) Cell migration ability evaluated by wound healing assay under different treatments. ∗ vs. Control; # vs. H/R; & vs. H/R + PD-L1@nmEVs, p < 0.05.

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: In Vitro, Labeling, Incubation, Expressing, Fluorescence, BrdU Incorporation Assay, Staining, Flow Cytometry, Microscopy, Activity Assay, Migration, Wound Healing Assay, Control

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: Res-PD-L1@nmEVs Restores Mitochondrial Homeostasis and Improves Energy Metabolism BEAS-2B cells were pretreated with Res, nEVs, PD-L1@mEVs, PD-L1@nmEVs, or Res-PD-L1@nmEVs followed by H/R stimulation for subsequent analysis. (A) Representative immunofluorescence images showing the expression and localization of PINK1 (green) and the mitochondrial marker TOMM20 (red), indicating activation of mitophagy. Nuclei were stained with DAPI (blue). Scale bar: 50 μm. (B) Quantitative analysis of PINK1 fluorescence intensity. (C) Expression and localization of autophagy-related proteins LC3B and Beclin-1 detected by immunofluorescence. (D-E) Quantitative analysis of LC3B (D) and Beclin-1 (E) fluorescence intensity. (F) Mitochondrial membrane potential assessed by JC-1 staining and flow cytometry. (G) Oxygen consumption rate (OCR) profiles of lung epithelial cells under different treatments. (H-K) Key mitochondrial respiration parameters: basal respiration (H), maximal respiration (I), proton leak (J), and ATP production (K). (L) Representative confocal microscopy images of mitochondria stained with MitoTracker (green) and lysosomes stained with LysoTracker (red), demonstrating mitochondrial-lysosomal colocalization. Scale bar: 5 μm ∗ vs. Control; # vs. H/R; & vs. H/R + PD-L1@nmEVs, p < 0.05.

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: Immunofluorescence, Expressing, Marker, Activation Assay, Staining, Fluorescence, Membrane, Flow Cytometry, Confocal Microscopy, Control

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: Res-PD-L1@nmEVs Suppresses Neutrophil Activation HL60 cells were differentiated into neutrophil-like cells using DMSO and subsequently stimulated with TNF-α to induce activation under conditions simulating IRI. The effects of Res, nEVs, PD-L1@mEVs, PD-L1@nmEVs, and Res-PD-L1@nmEVs on neutrophil activation were evaluated. (A) Cell surface PD-1 expression analyzed by flow cytometry. (B) Representative immunofluorescence images of CD206 expression (red). Nuclei were stained with DAPI (blue). Scale bar: 50 μm. (C) Flow cytometric analysis of cell surface CD206 expression. (D) Flow cytometric analysis of cell surface CD95 expression. (E-G) Levels of myeloperoxidase (MPO) (E), neutrophil elastase (NE) (F), and MMP-9 (G) in neutrophil culture supernatants, measured by ELISA. (H-J) BEAS-2B cells were co-cultured with neutrophils in the presence or absence of TNF-α stimulation. Apoptosis levels (I) and migration capacity (J) of BEAS-2B cells were assessed under different treatment conditions. ∗ vs. Control; # vs. TNF-a; & vs. TNF-a+PD-L1@nmEVs, p < 0.05.

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: Activation Assay, Expressing, Flow Cytometry, Immunofluorescence, Staining, Enzyme-linked Immunosorbent Assay, Cell Culture, Migration, Control

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: Nebulized Res-PD-L1@nmEVs Target and Attenuate Lung Ischemia-Reperfusion Injury (A) Experimental timeline: rats undergoing lung IRI received nebulized treatments (Res, nEVs, PD-L1@mEVs, PD-L1@nmEVs, or Res-PD-L1@nmEVs) before ischemia and after reperfusion, with sample collection 2 h post-reperfusion. (B) Ex vivo organ fluorescence imaging 24 h after intravenous or bronchial nebulization of DiR-labeled Res-PD-L1@nmEVs. (C) In vivo lung distribution of nebulized DiL-labeled PD-L1@mEVs and PD-L1@nmEVs evaluated using a small animal dynamic imaging system. Blue: CD31 (vascular marker), Red: DiL. (D-E) Quantitative fluorescence intensity in ex vivo organs (heart, liver, spleen, lungs, kidneys) at 0–24 h after bronchial nebulization of DiR-labeled Res-PD-L1@nmEVs in Sham and IRI groups. (F-G) Representative H&E-stained lung sections (F) and corresponding lung injury scores (G). (H) Lung wet/dry weight ratio. (I-K) Levels of inflammatory cytokines in lung tissue. (L-N) Pulmonary oxidative stress markers: T-SOD2 activity (L), GSH/GSSG ratio (M), and MDA content (N). (O) Representative fluorescence images of ROS in lung tissue. Scale bar: 50 μm. (P-R) Immunofluorescence staining and co-localization of tight junction proteins Occludin-1 (green) and ZO-1 (red) in lung tissues (DAPI: blue). Scale bar: 50 μm. Quantitative analysis of ZO-1 (Q) and Occludin-1 (R) fluorescence intensity. ∗ vs. Sham; # vs. IRI; & vs. IRI + PD-L1@nmEVs, p < 0.05.

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: Ex Vivo, Fluorescence, Imaging, Labeling, In Vivo, Marker, Staining, Activity Assay, Immunofluorescence

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: Res-PD-L1@nmEVs Suppresses Neutrophil Activation and Preserves Mitochondrial Integrity via PD-L1 Delivery (A-B) Rats subjected to lung IRI received nebulized administration of different formulations (Res, nEVs, PD-L1@mEVs, PD-L1@nmEVs, or Res-PD-L1@nmEVs) before ischemia and after reperfusion. Lung tissues were collected 2 h post-reperfusion. (A) Representative immunofluorescence images showing the expression and localization of CD11b (green), MPO (red), and PD-1 (yellow) in lung sections across treatment groups. (B) Enlarged view of the IRI group from (A). (C-D) mRNA levels of CD95 (C) and CD206 (D) in lung tissues. (E-F) Levels of myeloperoxidase (MPO) (E) and matrix metalloproteinase-9 (MMP-9) (F) in bronchoalveolar lavage fluid (BALF). (G-I) (G) Representative transmission electron microscopy (TEM) images of lung tissues (scale bar: 2 μm). (H) Proportion of damaged mitochondria. (I) Average number of mitophagic events per cell. (J) Immunofluorescence co-localization of mitochondrial marker TOMM20 (red) and EpCAM (green) in lung tissues (nuclei stained with DAPI, scale bar: 50 μm). (K-L) Protein expression levels of Beclin-1 (K) and LC3 (L) in lung tissues, with insets showing immunofluorescence co-localization of Beclin-1 (green) and LC3 (red) across treatment groups (nuclei stained with DAPI, scale bar: 50 μm). ∗ vs. Sham; # vs. IRI; & vs. IRI + PD-L1@nmEVs, p < 0.05.

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: Activation Assay, Immunofluorescence, Expressing, Transmission Assay, Electron Microscopy, Marker, Staining

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: Transcriptomic Analysis Reveals the Mechanism of Res-PD-L1@nmEVs Against IRI-Induced Lung Injury (A-B) Transcriptome sequencing of lung tissues from the Res-PD-L1@nmEVs-treated IRI group (N = 3) and the IRI-only group (N = 3). (A) Volcano plot and (B) heatmap display differentially expressed genes (DEGs) between the IRI + Res-PD-L1@nmEVs and IRI groups. (C-D) GO term and KEGG pathway enrichment analyses of upregulated DEGs after Res-PD-L1@nmEVs treatment. (E-F) GO term and KEGG pathway enrichment analyses of downregulated DEGs following Res-PD-L1@nmEVs treatment. (G-J) Gene Set Enrichment Analysis (GSEA) revealed enrichment in energy metabolism pathways (G) (TCA cycle and oxidative phosphorylation), biosynthetic pathways (H) (ribosome, amino acid biosynthesis, DNA replication), immune pathways (I) (allograft rejection, PD-L1 expression and PD-1 checkpoint pathway), and inflammatory responses (J) (chemokine signaling pathway, ECM-receptor interaction, cytokine-cytokine receptor interaction).

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: Sequencing, Phospho-proteomics, Expressing

Journal: Bioactive Materials

Article Title: Inhalable PD-L1-engineered hybrid cellular vesicles suppress excessive neutrophil activation and restore mitochondrial homeostasis to alleviate ischemia–reperfusion lung injury and pneumonia

doi: 10.1016/j.bioactmat.2026.03.024

Figure Lengend Snippet: Res-PD-L1@nmEVs Effectively Attenuates MRSA-Induced Pneumonia (A-B) Rats with MRSA-induced pneumonia received three bronchial nebulization treatments over one week with different formulations (Res, nEVs, PD-L1@mEVs, PD-L1@nmEVs, or Res-PD-L1@nmEVs). (A) Representative H&E-stained lung sections and (B) corresponding lung injury scores are shown (n = 5). (C) TUNEL staining of lung tissues to assess apoptosis. (D) Representative micro-CT images of anesthetized rats. (E-G) Flow cytometric analysis of immune cell proportions in lung single-cell suspensions: CD8 + T cells (E), neutrophils (F), and classical monocytes (G). (H-J) Plasma levels of inflammatory cytokines IL-6 (H), IL-1β (I), and TNF-α (J) (n = 5). (K) Immunofluorescence staining of tight junction proteins Occludin (green) and ZO-1 (red) in lung tissues (nuclei stained with DAPI). Scale bar: 50 μm. (L-N) Pulmonary function parameters: lung compliance (L), airway resistance (M), and oxygenation index (N) (n = 4). ∗ vs. Sham; # vs. MRSA; & vs. MRSA + PD-L1@nmEVs, p < 0.05.

Article Snippet: For assessing PD-L1 overexpression efficiency, the primary antibodies included PD-L1 (ET1701-4, HUABIO, China) and β-actin (66009-1, Proteintech, China).

Techniques: Staining, TUNEL Assay, Micro-CT, Single Cell, Clinical Proteomics, Immunofluorescence

Journal: Bioactive Materials

Article Title: Spatiotemporally engineered microneedle for microenvironment remodeling propels mucosal regeneration after tracheal mucosal injury

doi: 10.1016/j.bioactmat.2026.01.026

Figure Lengend Snippet: Gel-AgNA/MgGA MN promote mucosal regeneration. (a) HE and Safranin O staining of rabbit tracheal samples harvested at Day 10 post-operation after treated with Gel, Gel-AgNA, Gel-MgGA, and Gel-AgNA/MgGA MN. (b) IF staining of CK14 (marker of basal cells, red) and AC-Tub (marker of cilia cell, green). (c) IF staining of ZO-1 (marker of tight junctions, orange). (d, e) Quantitative analysis of regenerated epithelial coverage and thickness (n = 9). (f) Masson and Sirius Red staining for collagen evaluation after various treatments (n = 5). Quantitative analysis of collagen volume fraction (g) and fiber orientation (h) . The pentagram indicates luminal side of trachea.

Article Snippet: Immunofluorescence staining of CK14 (Abcam, ab181595), AC-Tub (Proteintech, 66200-1-Ig), ZO-1 (Proteintech, 21773-1-AP), and Immunohistochemical (IHC) staining for CD31 (Servicebio, S1002) were conducted to reveal the conditions of mucosal regeneration, according to previous literature [ ].

Techniques: Staining, Marker

Journal: Bioactive Materials

Article Title: A foam cell-targeted lipophagy restoration strategy stabilizes vulnerable atherosclerotic plaques

doi: 10.1016/j.bioactmat.2026.02.041

Figure Lengend Snippet: Schematic of the anti-atherosclerotic mechanism of OPN-HMCN@MLT. ( A ) The study commenced with the synthesis of mesoporous carbon nanospheres (MCN) functionalized with an OPN-binding peptide and hyaluronic acid to construct the OPN-HMCN nanoplatform. The OPN-binding peptide was designed to recognize OPN enriched in the extracellular matrix and on the surface of foam cells, thereby enabling selective accumulation in OPN-rich pathological regions. Following OPN recognition, OPN-HMCN@MLT undergoes CD44-dependent endocytosis. Melatonin (MLT), a lipid autophagy–promoting agent, was subsequently encapsulated within the nanocarrier to form OPN-HMCN@MLT. Firstly, the released MLT can bind to and upregulate the expression of PPARα and PPARγ, which then promote the expression of downstream genes (ABCA1, ABCG1, ACOX-1, and CTP1A) and trigger the lipophagy. ( B ) Subsequently, its lipophagy-enhancing effects, including ABCA1/G1-mediated cholesterol efflux and CTP1A/ACOX-1-mediated mitochondrial fatty acid oxidation, were studied to confirm the reversal of foam cell formation. ( C ) These effects eventually promote foam cells to reverse into macrophages. Abbreviations: MCN, mesoporous carbon nanoparticle; OPN, osteopontin; MLT, melatonin; LDL, low-density lipoprotein; ox-LDL, oxidized low-density lipoprotein; PA, Photoacoustic.

Article Snippet: To block nonspecific binding, membranes were incubated with 5% skim milk for 1 h. Thereafter, membranes were incubated overnight at 4 °C with primary antibodies against ABCA1, ABCG1, ACOX1, CPT1A, LC3 (ab192890, 1:2000, abcam), LAMP1 (84658-5-RR, 1:8000, Proteintech), PPARα (66826-1-Ig, 1:3000, Proteintech), PPARγ (66936-1-Ig, 1:10000, Proteintech), P62 (18420-1-AP, 1:10000, Proteintech), MCAD (55210-1-AP, 1:3000, Proteintech), LCAD (17526-1-AP, 1:10000, Proteintech), tubulin (80762-1-RR, 1:10000, Proteintech), GAPDH (60004-1-Ig, 1:50000, Proteintech), and β-actin (66009-1-Ig, 1:20000, Proteintech).

Techniques: Binding Assay, Construct, Expressing