nuclear fast red counterstain  (Vector Laboratories)

Journal: bioRxiv

Article Title: Early Binding of Anti-Amyloid Antibodies to CAA Drives Complement Activation, Inflammation and ARIA in Mice

doi: 10.64898/2026.03.04.709591

Figure Lengend Snippet: a, Schematic of acute single-dose immunization in 19-month-old APP NL-G-F KI mice (n=3-4/group) with biotinylated 3D6 or IgG2a mAb (25 mg/kg, i.p.), followed by euthanasia at 24 h. b, Brain sections stained with Amylo-Glo (AG) for amyloid, Collagen-IV for blood vessels’ basement membrane, Streptavidin 555 for biotinylated 3D6 or IgG2a, and endothelial marker CD31 in IgG2a and 3D6-biotinylated mAb-injected mice; images taken from the leptomeningeal penetrating vessels along the cortical pial surface. Arrowheads point towards CAA-bound Streptavidin 555, indicative of biotinylated mAb binding; asterisks indicate plaques. c–d , Brain sections labeled with AG and Streptavidin-AF555 showing biotinylated mAb distribution in c, leptomeningeal vessels, and d, large parenchymal arterioles. Arrowheads indicate CAA-associated mAb binding and C1q deposition observed in 3D6-treated mice. e, Schematic of acute immunization in 25-month-old APP NL-G-F KI mice (n= 7-9/group) treated with anti-Aβ 3D6 IgG2a mAb or IgG2a isotype control. f, Brain sections stained for aggregated Aβ, anti-mouse IgG2a (to detect 3D6 and IgG2a), and C1q in IgG2a control- and 3D6-treated mice. Arrows indicate cerebellar meningeal vessel-associated labeling; asterisks mark parenchymal plaque labeling. Adjacent sections were stained with Prussian blue (counterstained with nuclear fast red) for microhemorrhages and H&E for RBC extravasation. g, Triple labeling with AG, anti-mouse IgG2a, and collagen-IV to distinguish plaque (AG⁺AntiMsIgG2a⁺ColIV⁻) and vascular (AG⁺AntiMsIgG2a⁺ColIV⁺) mAb binding in 3D6-treated brain sections. h, Quantification of % cerebellar plaque vs CAA labeling of mAb in a subset of 3D6 treated mice (n=5), *p < 0.05, paired t-test. Scale bar: b=50 µm; c,d,f =100 µm; g = 250 µm.

Article Snippet: After a quick rinse in MilliQ water, sections were counterstained with Nuclear Fast Red Counterstain (Vector Laboratories, Inc, H-3403-500) followed by dehydration steps in ethanol and Histoclear.

Techniques: Staining, Membrane, Marker, Injection, Binding Assay, Labeling, Control

Journal: bioRxiv

Article Title: Early Binding of Anti-Amyloid Antibodies to CAA Drives Complement Activation, Inflammation and ARIA in Mice

doi: 10.64898/2026.03.04.709591

Figure Lengend Snippet: a, Schematic of 7-week treatment in 16.5-month-old APP/PS1dE9;hAPOE4 mice (n = 7-8/group) with 3D6 or IgG2a control mAb. b, Prussian blue-labeled hemosiderin deposits in cortex indicating microhemorrhage (asterisks). Scale bar: 50 µm. c, Quantification of Prussian blue–positive area (%) in the whole sagittal brain section; Mann-Whitney test, p < 0.0005. d, Amylo-Glo (AG)–positive fibrillar amyloid area (%) in cortex; unpaired t-test, p < 0.0005. e, Prussian blue staining with eosin counterstain in cortex showing hemosiderin deposits (asterisks) and red-orange cytoplasm of extravasated RBCs (arrows). Scale bar: 100 µm. f, Immunostaining with anti-mouse IgG2a fluorescently-tagged secondary antibody, C1q and AG in brain sections from 3D6- and IgG2a-treated mice. Scale bar: 50 µm. Representative immunofluorescence staining in the g, cortex and h, cerebellum showing C1q and activated C3 fragments C3b/iC3b/C3c deposition near AG-positive plaques (asterisks) and vascular amyloid (arrow), Scale bar in g & h : 250 µm. Quantification of % immunoreactivity (IR) for i, C1q; j, C1q + CD31 + AG + colocalized area; k, activated C3 fragments C3b/iC3b/C3c; and l, activated C3 fragments + CD31 + AG + colocalization in cerebellum. m, Levels of complement C3 in the plasma following 7-weeks of passive immunization. Unpaired t-test in j, k and Mann-Whitney test for i, l . *p<0.05 and **p<0.005, ***p<0.0005. Data are expressed as mean ± SEM.

Article Snippet: After a quick rinse in MilliQ water, sections were counterstained with Nuclear Fast Red Counterstain (Vector Laboratories, Inc, H-3403-500) followed by dehydration steps in ethanol and Histoclear.

Techniques: Control, Labeling, MANN-WHITNEY, Staining, Immunostaining, Immunofluorescence, Clinical Proteomics

Journal: Acta Physiologica (Oxford, England)

Article Title: Kisspeptin Restores Placental mTOR Signaling and Improves Glucose Homeostasis Mediators Disrupted by Maternal Hypothyroidism in Rats

doi: 10.1111/apha.70188

Figure Lengend Snippet: Assessment of placental morphology in control, hypothyroid, and Kisspeptin‐10 (Kp10)‐treated hypothyroid rats. (A) Photomicrographs of placentas at GD 14 (Hematoxylin & Eosin; Bar = 2.5 mm). (B) Absolute volume of the placental zones at GD 14 and 18. (C) Photomicrographs of PAS staining in the junctional zone (PAS; Fast Green; Bar = 50 μm). (D) Area in pixels stained by PAS at GD 14 and 18. (E) Photomicrographs of the double staining by cytokeratin + vimentin (Streptavidin‐biotin‐peroxidase; Alkaline Phosphatase‐BCIP/NBT; nuclear Fast Red; Bar = 20 μm) (F) Absolute volume of the compartments of the labyrinth zone at GD 14 and 18. (G) Surface area of the vasculature of the labyrinth area at GD 14 and 18. (H) Total fetal capillary length at GD 14 and 18. (I) Fetal capillary area at GD 14 and 18. (J) Fetal capillary diameter at GD 14 and 18. (K) Interhaemal membrane thickness at GD 14 and 18. (L) Theoretical diffusion capacity of the interhaemal membrane at GD 14 and 18. (M) Specific diffusion capacity of the interhaemal membrane at GD 14 and 18. (Mean ± SEM). Significant differences are indicated by * p < 0.05, ** p < 0.01 for one‐way ANOVA followed by SNK test, and # p < 0.05 for Student's t ‐test. BD, basal decidua; GD, gestational day; Gly, glycogen cells; Green bar, interhaemal membraneJZ, junctional zone; LZ, labyrinth zone; MVS, maternal vascular space; PAS, Periodic acid‐Schiff; SpT, spongiotrophoblast; TB, trophoblast; TGC, trophoblast giant cells.

Article Snippet: The next day, sections were kept at room temperature (2 h), and incubated with alkaline phosphatase–conjugated secondary antibody (ab6722, 1:500, Abcam, 1 h) and developed with NBT/BCIP (34 042, Thermo Scientific, 10 min) followed by Fast Red counterstaining (H‐3403, Vector Laboratories, 4 min).

Techniques: Control, Staining, Double Staining, Membrane, Diffusion-based Assay