Journal: Frontiers in Immunology

Article Title: Erythrocytes of the common carp are immune sentinels that sense pathogen molecular patterns, engulf particles and secrete pro-inflammatory cytokines against bacterial infection

doi: 10.3389/fimmu.2024.1407237

Figure Lengend Snippet: (A) Flow cytometry analysis of the head kidney leukocytes (HKLs, positive control), and red blood cells (RBCs), after incubation with RPMI 1640 or carboxylate-modified latex beads. Distinct populations of HKLs, RBCs, and latex beads were identified based on their side scatter area (SSC-A) versus forward scatter area (FSC-A) profiles, as shown in the top row. The bottom row illustrates the level of green fluorescence intensity (y-axes), representing the fluorescence of latex beads in the FITC channel, versus FSC-A (x-axes) for the same corresponding experimental conditions presented in the top row. A single gated subpopulation is included in each plot: host cells in the top row and latex bead-associated host cells in the bottom row. We included the proportion/percentage of each subpopulation out of total events next to their corresponding plots which e.g., enumerates the number of phagocytic HKLs or latex bead-associated RBCs. (B) Fluorescence microscopy images of (from left to right): beads only, head kidney leukocytes incubated with beads, and the erythrocytes incubated with beads after 1 hour. These images are derived from the same specimens included in (A) .

Article Snippet: The analysis of the images and the 3D model was done on Microscopy Image Browser (MIB MATLAB 2.84) ( ) software and Amira (Thermo Fisher Scientific, USA) platform for visualization, processing, and analysis of 3D models.

Techniques: Flow Cytometry, Positive Control, Incubation, Modification, Fluorescence, Microscopy, Derivative Assay

Journal: Frontiers in Immunology

Article Title: Erythrocytes of the common carp are immune sentinels that sense pathogen molecular patterns, engulf particles and secrete pro-inflammatory cytokines against bacterial infection

doi: 10.3389/fimmu.2024.1407237

Figure Lengend Snippet: Immunofluorescence of the erythrocytes incubated with carboxylate-modified latex beads (A, B) . Erythrocytes were stained with Hoechst33258 (DNA; blue), CellMask (RBC membranes; red), and incubated with latex beads (Alexa Fluor™ 555; orange). All pictures were also captured and merged using differential interference contrast (DIC). Apart from adherence of beads to the surface of RBCs (A, B) , beads were also internalized within the membrane accompanied by co-staining with a membrane-specific dye (CellMask™) of the RBCs: (C) subcellular presence of beads (indicated by white arrowheads) within an erythrocyte. (D) Erythrocytes forming filamentous membrane extensions in the presence of beads (also indicated by white arrowheads). Scale bars: 10 μm. (E) Transmission electron microscopy (1-4) and the serial block face-scanning electron microscopy (SBF-SEM) (5-6) of the erythrocytes incubated with carboxylate-modified polystyrene latex beads (0.5 μm) for 1h (1), 2h (2-3) or 4h (4). The electron micrographs show the adhesion of the beads to the erythrocytes (1-2) or engulfment of the beads (red arrows) (3-4). Scale bars: 2 μm. (5-6) Segmented portion of 3D SBF-SEM of bead engulfment by erythrocytes. Organelle segmentation is color-coded. Red: erythrocytes, Turquoise: latex beads. Scale bars: 1µm.

Article Snippet: The analysis of the images and the 3D model was done on Microscopy Image Browser (MIB MATLAB 2.84) ( ) software and Amira (Thermo Fisher Scientific, USA) platform for visualization, processing, and analysis of 3D models.

Techniques: Immunofluorescence, Incubation, Modification, Staining, Membrane, Transmission Assay, Electron Microscopy, Blocking Assay