title: S-antigen immunoreactivity in human pineal glands and pineal parenchymal tumors. A monoclonal antibody study.
abstract: Using a four-step immunoperoxidase (PAP) method and the monoclonal antibody MAbA9-C6 (MAbA9-C6), which defines an epitope of the retinal S-antigen (S-Ag), we investigated the S-Ag immunoreactivity in human fetal, newborn, infantile and adult pineal glands and in 13 human pineal parenchymal tumors. S-Ag immunoreactivity was demonstrated in a few cells in one of the four fetal and in both infantile glands. Eight of nine adult pineal glands contained isolated MAbA9-C6-positive cells. In two of seven pineocytomas showing neuronal or gangliogliomatous differentiation a few scattered cells displayed S-Ag positivity; two of four pineoblastomas contained small groups of strongly immunoreactive neoplastic cells; two malignant pineocytomas did not demonstrate any S-Ag immunoreactivity. Our results indicate that isolated cells in human pineal gland retain some of the cytochemical characteristics of photoreceptor cells recognized by the MAbA9-C6, and that S-Ag immunoreactivity may be occasionally expressed in pineal parenchymal tumors.
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D000941:Antigens; D000951:Antigens, Neoplasm; D019393:Arrestin; D001932:Brain Neoplasms / Q000276:immunology* / Q000473:pathology; D005136:Eye Proteins; D005333:Fetus; D006801:Humans; D007124:Immunoenzyme Techniques; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D010870:Pineal Gland / Q000276:immunology*; D010871:Pinealoma / Q000276:immunology* / Q000473:pathology
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens; D000951:Antigens, Neoplasm; D019393:Arrestin; D005136:Eye Proteins