Journal: Acta Pharmaceutica Sinica. B
Article Title: Clostridium perfringens alpha toxin drives pathological NETosis via immature neutrophil mobilization and functional reprogramming
doi: 10.1016/j.apsb.2025.09.011
Figure Lengend Snippet: CPA directly induces NETosis in both murine and human neutrophils in vitro . (A) Representative immunofluorescence images of purified neutrophils from mice stimulated in vitro with PBS, CPA, or PMA (positive control). Cells were stained for CitH3 (red) and MPO (green). Scale bar = 10 μm. (B) Representative immunofluorescence images of purified neutrophils from humans stimulated in vitro with PBS, CPA, or PMA (positive control). Cells were stained for CitH3 (red) and MPO (green). Scale bar = 10 μm. (C) Flow cytometric analysis of intracellular ROS production in mice PBMCs stimulated in vitro with PBS, CPA, or Rosup (positive control). Histograms show DCFH-DA fluorescence within the gated neutrophil population. (D) Flow cytometric analysis of intracellular ROS production in human PBMCs stimulated in vitro . Histograms show DCFH-DA fluorescence within the gated neutrophil population. (E) Relative mRNA expression of NETs-associated genes in stimulated mice PBMCs ( Tlr4 , Padi4 , Hmox1 , Nfe2l2 , and Cybb ) and human PBMCs ( TLR4 , PADI4 , HMOX1 , NFE2L2 , and CYBB ), as determined by qPCR. Data are mean ± SD, n = 3. Statistical significance was determined using one-way ANOVA followed by Tukey’s multiple comparisons test (∗ P < 0.05; ∗∗ P < 0.01; ∗∗∗ P < 0.001 vs. PBS-treated. ns, not significant). (F) Representative Western blot detecting PAD4 and CitH3 protein levels in lysates from stimulated mice PBMCs and human PBMCs ( n = 3). (G) Densitometric quantification of the protein bands shown in (F). Data are mean ± SD, n = 3. Statistical significance was determined using one-way ANOVA followed by Tukey’s multiple comparisons test (∗ P < 0.05; ∗∗∗ P < 0.001 vs. PBS-treated. ns, not significant). (H) Caspase-3 activity measured by flow cytometry within the gated neutrophil population of stimulated mice PBMCs and human PBMCs. Data are mean ± SD, n = 3. Statistical significance was determined using an unpaired two-tailed t- test ( vs. PBS-treated. ns, not significant). (I) Flow cytometric analysis of apoptosis in stimulated mice PBMCs and human PBMCs using Annexin V and 7-AAD staining. Representative dot plots are shown. The bar graph shows the quantification of the live cell percentage (Annexin V − /7-AAD - ) within the gated neutrophil population. Data are mean ± SD, n = 3. Statistical significance was determined using an unpaired two-tailed t- test (∗∗∗ P < 0.001 vs. PBS-treated. ns, not significant).
Article Snippet: Cell apoptosis was measured using an Annexin V-PE/7AAD apoptosis kit (MULTISCIENCES, AT104-100, Hangzhou, China) and Cleaved Caspase-3 (Asp175) Antibody (Alexa Fluor® 488 Conjugate) (Cell Signaling Technology, 9669S, Danvers, MA, USA).
Techniques: In Vitro, Immunofluorescence, Purification, Positive Control, Staining, Fluorescence, Expressing, Western Blot, Activity Assay, Flow Cytometry, Two Tailed Test