Demonstration of the mucosal lectins in the epithelial cells of internal and external body surface tissues in pufferfish (Fugu rubripes)

We have previously identified two novel mannose-specific lectins, skin- and intestine-type pufflectins, in the pufferfish, Fugu rubripes [J. Biol. Chem. 278 (2003) 20882]. In the present study, the localization of the lectins and their producing cells were analyzed with antibody and anti-sense probe that recognize both types of pufflectin. Using immunohistochemistry, pufflectins were detected exclusively in epithelial cells in the skin, gills, oral cavity wall and esophagus, whereas in both mucous and epithelial cells in the intestine. Messenger RNAs for pufflectins were detected only in epithelial cells of these tissues with in situ hybridization, suggesting that epithelial cells are able to produce the lectins. Pufflectins are produced and distributed in cells that cover the external and internal body surfaces, which might mean that Fugu have a common immunological system on both surfaces.