Lectin histochemistry shows the comparative biosynthesis and cellular biodistribution of alpha L-fucose residues in some tissues of tetrapoda representatives.

Fucose is a monosaccharide that plays several immunological roles. This study investigated the comparative biosynthesis and cellular biodistribution of fucose residues in some tissues of tetrapoda representatives using lectin histochemistry. In this study, the mouse was used as a representative for mammalian, pigeon for avian, lizard for reptilian, and toad for amphibians. The localization of the fucose residues was seen in several cell types of mice ileum, such as villi microfold (M) cells, goblet cells, some of intestinal crypts cells, and lamina propria cells. In other tetrapoda representatives, fucose was only seen in M cells of lizard ileum and some cells of villi lamina propria of pigeon, lizard, and toad. It was also observed in the pancreatic acinar cells of the mouse and some cell aggregations of pancreatic parenchyma of the lizard. Contrarily, it was not seen either in pigeon or in toad pancreases parenchyma. Spleen of all animals showed the fucose residues in some splenic cells in the red pulp only, barring the white pulp. The liver parenchyma of all tetrapoda representatives hadn't fucose residues. The fucose cellular biodistribution in some cells of tetrapoda representatives differed based on the cell type. In the mouse, it was highly seen in the apical cytoplasm of the villi M cells as well as in the cup-like part of goblet cells. In addition, it was seen as "rings" in the granule membranes of the Ulex europeaus agglutinin I (UEAI(+)) cells in the intestinal crypts cells. Furthermore, the UEAI(+) cells in the lamina propria showed fucose granules in their cytoplasm. There is no clear evidence about the relation between the cellular biosynthesis of fucose residues and mucosal immune cells. The role of fucose residues in the pancreatic acinar cells are not well understood and need further investigations. In this study, fucose residues were synthesized in several types of cells in the mouse ileum, spleen and pancreas as compared with other tetrapoda. The data obtained from this study can help us to get more information about the cellular biodistribution and synthesis of fucose residues in several animal species rather than mammalians.