Journal: iScience

Article Title: Polystyrene microplastics cross the murine intestine and induce inflammatory cell death after phagocytosis by human monocytes and neutrophils

doi: 10.1016/j.isci.2025.114076

Figure Lengend Snippet: Phagocytosis of 10 μm PS particles is complement-dependent (A) Phagocytosis of 10 μm Nile Red stained PS particles (red) by f-MLF stimulated calceinAM stained neutrophils (green) measured on a Leica Stellaris5 confocal microscope. PS particles were pre-incubated with human pooled serum (HPS). The right graph represents the fluorescent intensity of the green neutrophils (green graph line) and red 10 μm PS particles (white graph line) along the vertical green line in the image on the left. Timepoint shown is 120 min. (B) Phagocytosis of 10 μm Nile Red stained PS particles (red) by f-MLF stimulated calceinAM stained neutrophils (green) on a Leica Stellaris5 confocal microscope. PS particles were pre-incubated with HPS. Images on the right and bottom show the z dimension along the green lines in the XY image on the top left. Timepoint shown is 120 min. (C) Phagocytosis of 10 μm uncolored PS particles (gray) by f-MLF stimulated calceinAM stained neutrophils (green) on a Leica Stellaris5 confocal microscope. PS particles were pre-incubated with HPS or heat-inactivated HPS and subsequently cultured in HPS, HPS +28 μM compstatin, HPS +0.1 mg/mL FcR inhibitor, or heat-inactivated HPS. Timepoint shown is 120 min. Scale bar is 50 μm. Neutrophil phagocytosis at 120 min was manually quantified in two images per 3 different donors. Results are shown as means plus standard deviations. Controls were compared to the different treatments with a paired one-way ANOVA with Dunnett multiple comparison correction. ∗∗ p < 0.01, ∗∗∗ p < 0.001.

Article Snippet: In order to test the requirements of neutrophil phagocytosis of 10 μm PS particles, PS particles were pre-incubated with HPS or heat-inactivated HPS and subsequently cultured in HPS, HPS + 28μM of the complement inhibitor compstatin (Tocris bioscience), HPS + 0.1mg/ml of polyclonal antibodies binding and inhibiting the FcR (eBioscience) or heat-inactivated HPS.

Techniques: Staining, Microscopy, Incubation, Cell Culture, Comparison

Journal: Nature Communications

Article Title: Potent neutralization by antibodies targeting the MPXV A28 protein

doi: 10.1038/s41467-025-66344-0

Figure Lengend Snippet: a Neutralization kinetics of VACV IHDJ by anti-MPXV mAbs at IC 50 concentrations with 1.5% NHS (3% during pre-incubation). NHS and mAbs were added at 10-min intervals from 2 h before to 2 h after infection. b Neutralization in the presence of 1.5% NHS (3% during pre-incubation) and 6 consecutive 4-fold dilutions of C5-IN-1 starting from 10 μM. c Same as ( b ) but with 8 consecutive 5-fold dilutions of a C3 inhibitor AMY-101 starting from 10 μM. d Neutralization in the presence of 1.5% NHS (3% during pre-incubation) or C1q- or C3-depleted human serum. e C1q deposition on VACV IHDJ virions ( ~ 5 × 10⁶ PFU) incubated with 1.5% NHS and 10 μg/mL mAbs. Left panel: flow cytometry plots, pre-gated for virions using GFP followed by staining for C1q-AF647. Right panel: median fluorescence intensity. f-h TEM visualization of mAb and complement factors C1q, and C3 deposition on virions. Purified MV particles were incubated with 10 μg/mL of either mAb 7M1162 anti-H3 ( f ), 8M2110 anti-A28 ( g ) or MGO53 isotype control ( h ) and 1.5% NHS. IgG, C1q, and C3 deposition were visualized using anti-human IgG gold nanoparticles (10 nm) or secondary mouse anti-C1q and mouse anti-C3, followed by labeling with anti-mouse gold nanoparticles (20 nm). Anti-H3 and anti-A28 mAbs are shown in magenta and green, respectively; anti-M1 (7D11) in black; MGO53 in gray. IC 50 concentrations for panels ( a – d ) were: 15 μg/mL (7M1162), 0.125 μg/mL (8M2110), 1.25 μg/mL (10M2146), and 62.5 μg/mL (10M2154). Spearman correlation was used in ( a ) to determine the relationship between pre-incubation times and neutralization. Standard curves were determined by fitting values using simple linear regression for ( a ) and Inhibitor vs. normalized response (Variable slopes) nonlinear regression for ( b - c ). Standard deviation of the mean is shown for all values in ( a – d ). The percentages of complement sources indicated represent the final concentrations in the infected wells. Data are representative of two independent experiments with similar results using technical replicates: n = 3 for ( a ), n = 5 for ( b ), n = 6 for ( c ), and n = 3 for ( d ). Source data are provided as a Source Data file.

Article Snippet: For experiments involving selective complement inhibitors, mAbs and NHS mixtures were incubated with either 6 consecutive 4-fold dilutions, starting from 10 μM of a selective complement C5 inhibitor, C5-IN-1 (Compound 7- MedChemExpress), or 8 consecutive 5-fold dilutions, starting from 10 μM of a selective complement C3 inhibitor, CP40 (AMY-101- MedChemExpress).

Techniques: Neutralization, Incubation, Infection, Flow Cytometry, Staining, Fluorescence, Purification, Control, Labeling, Standard Deviation