Rahul K. Nelli
1 , Tyler A. Harm
1, Chris Siepker
1, Jennifer M. Groeltz-Thrush, Brianna Jones, Ning-Chieh Twu, Ariel S. Nenninger, Drew R. Magstadt, Eric R. Burrough, Pablo E. Piñeyro, Marta Mainenti, Silvia Carnaccini, Paul J. Plummer, and Todd M. Bell
Figure 3. Respiratory tract tissues from a US dairy cow infected with highly pathogenic avian influenza A(H5N1) virus, labeled with IAV-Np (yellow pseudocolor, DyLight 594), individually duplexed with MAL-I (red pseudocolor, Alexa Fluor 647), MAL-II (red pseudocolor, Alexa Fluor 647), and SNA (red pseudocolor, Alexa Fluor 647) using fluorescent staining. Representative merged images are shown for IAV-Np and MAL-I (A, D, G, J), IAV-Np and MAL-II (B, E, H, K), and IAV-Np and SNA (C, F, I, L). IAV-Np labeling was not detected within the respiratory tissue sections. Intense, granular to punctate, cytoplasmic MAL-I, MAL-II, and SNA labeling was observed in goblet cells (arrowheads) and glands of the trachea (A–C). Similar goblet cell labeling (arrowheads) for MAL-I (D) and MAL-II (E) was observed in the bronchi with weak SNA labeling (F). Multifocal, moderate, fibrillar, apical, membranous MAL-I (A) and MAL-II (B) labeling (white arrows) was observed on the tracheal epithelium. The respiratory epithelium of the bronchi, bronchioles, and alveoli had diffuse, moderate to intense, apical, fibrillar MAL-I labeling (white arrows) (D, G, J). The respiratory epithelium of the bronchi had multifocal, moderate, fibrillar, apical MAL-II labeling (white arrows) (E). The respiratory epithelium of the bronchioles and alveoli had diffuse MAL-II labeling (white arrows) (H, K). Intraluminal secretory material (asterisks) in the bronchi and bronchioles were intensely labeled with MAL-I and MAL-II (G, H). Membranous, granular SNA labeling (yellow arrows) was observed in intraepithelial and lamina proprial round cells in the trachea and bronchi (C, F). Scale bars indicate 50 μm. IAV-Np, influenza A virus nucleoprotein; MAL, Maackia amurensis lectin; SNA, Sambucus nigra lectin.