Cellular activities in the regulation of growth or adhesion/migration involve protein (lectin)-carbohydrate recognition at the cell surface. Members of the galectin family of endogenous lectins additionally bind distinct intracellular ligands. These interactions with protein targets explain the relevance of their nuclear and cytoplasmic presence. Expression profiling for galectins and accessible binding sites is a histochemical approach to link localization with cellular growth properties. Non-cross-reactive antibodies for the homodimeric (proto-type) galectins-1, -2 and -7 and the chimera-type galectin-3 (Gal-3) as well as the biotinylated lectins were tested. This analysis was performed with the FaDu squamous carcinoma cell line and long-term cultured human and porcine epidermal cells as models for malignant and normal cells of squamous cell epithelial origin. A set of antibodies was added for phenotypic cell characterization. Strong nuclear and cytoplasmic signals of galectins and the differential reactivity of labeled galectins support the notion of their individual properties. The length of the period of culture was effective in modulating marker expression. Cytochemical expression profiling is a prerequisite for the selection of distinct proteins for targeted modulation of gene expression as a step toward functional analysis.

• MeSH
• Cell Differentiation physiology   MeSH
• Cell Nucleus metabolism   ultrastructure   MeSH
• Epithelial Cells metabolism   MeSH
• Phenotype MeSH
• Galectins metabolism   MeSH
• Humans MeSH
• Cell Adhesion Molecules metabolism   MeSH
• Swine MeSH
• Growth Substances metabolism   MeSH
• Carbohydrates physiology   MeSH
• Signal Transduction physiology   MeSH
• Carcinoma, Squamous Cell metabolism   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Galectins MeSH
• Cell Adhesion Molecules MeSH
• Growth Substances MeSH
• Carbohydrates MeSH

Craniopharyngioma is a rare benign tumour originating from Rathke's pouch. This paper reports a tumour case studied with a set of markers defining protein-carbohydrate recognition. Expression of endogenous lectins and their reactive glycoligands is under differentiation-dependent control in many cell types. These parameters can be related to the degree of cell differentiation in tumours. Therefore, the expression patterns of endogenous lectins, namely galectins-1, -3, and -7, in the craniopharyngioma case were determined. Galectins-1 and -3 were also used to reveal glycoconjugates in cells and extracellular matrices, an approach that has heretofore relied largely on plant lectins. The staining pattern of craniopharyngioma is compared with that of two other types of ectodermally derived tumours, namely basal and squamous cell carcinomas. Clusters of polygonal and flattened cells with morphological characteristics of differentiated cells in the craniopharyngioma and the majority of poorly differentiated cells in squamous cell carcinomas were reactive with galectin-3. No binding of this probe was observed in cells of basal cell carcinomas and the majority of craniopharyngioma cells. In view of the lack of accessible binding in the basal layer of normal squamous epithelia where proliferative cells (including stem cells) are located, galectin-3 binding could be used to distinguish basal from suprabasal cells of squamous epithelial cells.

• MeSH
• Neoplasms, Basal Cell metabolism   pathology   MeSH
• Cell Differentiation physiology   MeSH
• Adult MeSH
• Epithelium metabolism   pathology   MeSH
• Epitopes MeSH
• Phenotype MeSH
• Microscopy, Fluorescence MeSH
• Galectins metabolism   MeSH
• Histocytochemistry MeSH
• Keratins metabolism   MeSH
• Craniopharyngioma metabolism   pathology   MeSH
• Lectins MeSH
• Humans MeSH
• Antibodies, Monoclonal MeSH
• Biomarkers, Tumor MeSH
• Pituitary Neoplasms metabolism   pathology   MeSH
• Polysaccharides metabolism   MeSH
• Carcinoma, Squamous Cell metabolism   pathology   MeSH
• Binding Sites MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Male MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH
• Research Support, Non-U.S. Gov't MeSH
• Comparative Study MeSH
• Names of Substances
• Epitopes MeSH
• Galectins MeSH
• Keratins MeSH
• Lectins MeSH
• Antibodies, Monoclonal MeSH
• Biomarkers, Tumor MeSH
• Polysaccharides MeSH

BACKGROUND/AIM: Components of the tear fluid contribute to the biochemical defence system of the eye. To reveal whether the immune mediator and lipopolysaccharide binding galectin-3 is present in tears, tear samples were collected from eyes in healthy and pathological states. Investigation of expression of galectin-3 and galectin-3 reactive glycoligands in normal human conjunctival and corneal epithelia was also initiated as a step to understand the role of galectin-3 in ocular surface pathology. METHODS: Immunoblot analysis using either a rabbit polyclonal or a mouse monoclonal antibody against galectin-3 was employed to detect galectin-3 in tear fluid. Galectin-3 expression in tissue specimens was detected by immunocytochemistry employing A1D6 mouse monoclonal antibody, and galectin-3 reactive glycoligands were visualised by lectin histochemistry using labelled galectin-3. RESULTS: Galectin-3 was found only in tears from patients with ocular surface disorders. It was expressed in normal corneal and conjunctival epithelia but not in lacrimal glands. Inflammatory leucocytes and goblet cells found in galectin-3 containing tear fluid also expressed galectin-3. Galectin-3 binding sites were detected on the surface of conjunctival and corneal epithelial cells co-localising with desmoglein. CONCLUSIONS: This study revealed expression of galectin-3 in tear fluid obtained from patients with eye diseases. The role of this endogenous lectin (produced by inflammatory as well as epithelial cells) in antimicrobial action and inflammation modulation could be expected.

• MeSH
• Antigens, Differentiation analysis   MeSH
• Electrophoresis, Polyacrylamide Gel MeSH
• Fluorescent Antibody Technique MeSH
• Galectin 3 MeSH
• Immunoblotting MeSH
• Conjunctiva metabolism   MeSH
• Leukocytes metabolism   MeSH
• Humans MeSH
• Luminescent Measurements MeSH
• Eye Diseases metabolism   MeSH
• Goblet Cells metabolism   MeSH
• Epithelium, Corneal metabolism   MeSH
• Tears chemistry   MeSH
• Blotting, Western MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Antigens, Differentiation MeSH
• Galectin 3 MeSH