HISTOCHEMICAL-STUDY OF LYMPHOCYSTIS DISEASE IN SKIN OF GILTHEAD SEABREAM, SPARUS-AURATA L

A battery of horseradish peroxidase-conjugated lectins (Con A, WGA and DBA), as well as conventional histochemical techniques (PAS, saponifi cation, Alcian Blue pH 0.1, 1, 2.5, chlorhydric hydrolisis, sialidase, Bromophenol blue, Tioglycollate reduction and Ferric-ferricyanide-FeI II) were used to study the content and distribution of carbohydrates, proteins and glycoconjugate sugar residues on the skin and on the lymp hocystis-infected cells of gilthead seabream, Sparus aurata. Variable amounts of glycoproteins containing sialic acid, N-acetyl-D-glucosamin e, N-acetyl-D-galactosamine, mannose and/or glucose residues were obse rved in the cuticle and mucous cells of the corporal skin, tails and f ins. Germinative and epithelial cells of the epidermis contained glyco gen, proteins, carboxylated groups, as well as glycoproteins with mann ose and/or glucose and N-acetyl-D-galactosamine residues. Hyaline caps ule of the mature lymphocystis-infected cells was strongly stained wit h PAS, Alcian Blue (pH 0.5 and 2.5) and weakly positive with Alcian Bl ue (pH 1). Con A reacted with the granular cytoplasm, specially around hyaline capsule, and with the basophilic intracytoplasmic inc lu a io ns develop ed in mature lymphocystis-infected cells of Sparus aurata s kin. These sugar residues (mannose and/or glucose), as well as N-acety l-D-glucosamine and/or sialic acid and N-acetyl-D-galactosamine were n ot detected in the hyaline capsule of the lymphocystis disease.