Journal: bioRxiv
Article Title: Nrf2 regulates ICAM-1–mediated neutrophil extracellular trap formation after traumatic brain injury
doi: 10.64898/2026.05.01.722360
Figure Lengend Snippet: Immunofluorescence analysis of NET formation in the pericontusional cortex of wild-type (WT), Nrf2⁻/⁻ , and ICAM-1⁻/⁻ mice following TBI. NETs were identified by co-localization of citrullinated histone H3 (H3Cit, a specific NET marker; red) and Ly6G (neutrophil marker; green). The nuclei were counterstained with DAPI (blue). Scale bar = 250 µm in the panels of first row, and 80 µm in the panels of second through fourth rows. Bar graphs show the quantification of H3Cit (B) and Ly6G (C) positive cells (n = 6/group). (D-F) Western blotting expression of PAD4, Ly6G, and H3Cit 24 hr after injury following genetic disruption of PAD4 (CRISPR/Cas9), pharmacological inhibition with GSK484, or DNase I, and the treatment with phorbol 12-myristate 13-acetate (PMA), or purified NETs in human brain microvascular endothelial cells (hBMVECs) exposed to injury. (E and F) Bar graphs represent densitometric quantification of H3Cit normalized to total H3 (E), and PAD4 and Ly6G normalized to β-actin (F) (n = 6/group). (G-I) Western blotting analysis of PAD4, Ly6G, and histone H3 citrullination in injured hBMVECs under Nrf2-deficient conditions and following inhibition of NET formation or ICAM-1 blockade. (H and I) Bar graphs represent densitometric quantification of PAD4 and Ly6G normalized to β-actin (H) and H3Cit normalized to total H3 (I) (n = 6/group). (J-L) Western blotting analysis of PAD4, Ly6G, and H3Cit expression in brain tissue from WT, Nrf2⁻/⁻ , and ICAM-1⁻/⁻ mice under control and TBI conditions. (K and L) Bar graphs represent densitometric quantification of PAD4 and Ly6G normalized to β-actin (H) and H3Cit normalized to total H3 (I) (n = 8/group). (M-N) Measurement of NET-associated myeloperoxidase (MPO) activity (M) and MPO–DNA complexes (N) in brain tissue lysates from WT, Nrf2⁻/⁻ , and ICAM-1⁻/⁻ mice following TBI (n= 8/group). All values are expressed as mean ± SEM. Statistical analysis was performed using one-way ANOVA in A, B, E, F, H, and I and two-way ANOVA in K-N, followed by Dunnett’s post hoc test. p < 0.05 statistically significant. ***P < 0.001 versus control; # P < 0.05, # P < 0.05 versus control siRNA; $$$ P < 0.001 versus injury in E, F, H, and I. ‘ns’ is not significant.
Article Snippet: Male and female C57/BL6 mice wild-type (WT), Nrf2 knockout ( Nrf2−/− ) mice and ICAM-1 knockout ( ICAM-1−/−) mice (9 weeks old, 20-25 g; Jackson Laboratory, Bar Harbor, ME) were used for this study.
Techniques: Immunofluorescence, Marker, Western Blot, Expressing, Disruption, CRISPR, Inhibition, Purification, Control, Activity Assay