Morphology of mucosa-associated lymphoid tissue in odontocetes

• Published in: Microscopy research and technique Vol. 79; no. 9; pp. 845 - 855
• Main Authors: Silva, Fernanda M. O., Guimarães, Juliana P., Vergara-Parente, Jociery E., Carvalho, Vitor L., Carolina, Ana, Meirelles, O., Marmontel, Miriam, Oliveira, Bruno S. S. P., Santos, Silvanise M., Becegato, Estella Z., Evangelista, Janaina S. A. M., Miglino, Maria Angelica
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.09.2016; Wiley Subscription Services, Inc
• Subjects: Adults; Arteries; cetaceans; Constants; Females; immunology; Lymphocytes; lymphoid system; MALT; Morphology; Pulmonary arteries; Transmission electron microscopy; cetaceans; immunology; MALT; lymphoid system
• ISSN: 1059-910X; 1097-0029
• DOI: 10.1002/jemt.22712

This study describes the mucosa‐associated lymphoid tissue (MALT) in odontocetes from the Brazilian coast and freshwater systems. Seven species were evaluated and tissue samples were analyzed by light, scanning and transmission electron microscopy, and immunohistochemistry. Laryngeal tonsil was a palpable oval mass located in the larynx, composed of a lymphoepithelial complex. Dense collections of lymphocytes were found in the skin of male fetus and calf. Clusters of lymphoid tissue were found in the uterine cervix of a reproductively active juvenile female and along the pulmonary artery of an adult female. Lymphoid tissues associated with the gastrointestinal tract were characterized by diffusely arranged or organized lymphocytes. The anal tonsil was composed of an aggregate of lymphoid tissue occurring exclusively in the anal canal, being composed of squamous epithelium branches. MALT was present in different tissues and organic systems of cetaceans, providing constant protection against mucosal pathogens present in their environment.