Lectin binding pattern in normal human labial mucosa.

The pattern of lectin binding in normal human labial mucosa was examined by light and electron microscopy using eight different lectins (ConA, LCA, WGA, UEA-1, RCA-1, SBA, DBA and PNA) and compared with the patterns in normal human skin and oesophageal mucosa. As seen by light microscopy, ConA, LCA, and WGA stained cell membranes in all layers of the mucosae. RCA-1 stained the plasma membrane of cells in the basal and middle layers, whereas cells in the superficial layers showed little positive staining. UEA-1, SBA, and PNA stained the cells in the middle layers weakly in some cases. No positive staining for DBA was seen. By electron microscopy, reaction product indicating ConA-binding sites was observed in the plasma membrane, cisternae of the endoplasmic reticulum, nuclear envelope and the Golgi apparatus. Binding of LCA, WGA, and RCA-1 was observed in the plasma membrane. These results show that the binding pattern of PNA, SBA, and RCA-1 in labial mucosa is different from that in the normal skin or oesophageal mucosa, although the labial mucosal epithelium, epidermis, and oesophageal epithelium are all stratified squamous epithelia. These differences in the cell-surface sugar residues are likely to be related to the possible functional differences in these tissues.

Immunohistochemical localization of amylase in sialoadenitis and salivary gland tumors.

Immunohistochemical demonstration of alpha-amylase has been made in sialoadenitis-involved tissue and salivary gland tumors, as well as in normal salivary glands. Immunoreactive alpha-amylase with trypsin pretreatment was confined to irregularly staining serous acinar cells in the parotid and submandibular glands, and to demilunes in sublingual glands. In obstructive adenitis, staining was irregular from high to negative in acini in early or intermediate stages. Dilated ductal segments contained cells positive for alpha-amylase in the early stage following obstruction. Pleomorphic adenomas were usually negative for alpha-amylase but in rare cases tumor epithelia stained variably positive; i.e., staining occurred throughout the cytoplasm or at the periphery or apical part of the tumor cells. Luminal cavities of tubular and duct-like structures contained alpha-amylase-positive material. Epithelia in Warthin's tumor were also negative in general; however, scattered single or grouped tumor cells containing alpha-amylase were found. Mucoepidermoid tumors were also negative, though slightly positive cells were found intermingled among the negative squamous and mucous tumor cells. Cystic lesions in mucoepidermoid tumor were sometimes positive in the wall cells together with material secreted into the lumen.

Bullous pemphigoid--a scanning electron microscopic study.

Skin blisters at different stages were taken from 4 patients with bullous pemphigoid and studied mainly by scanning electron microscopy. The under-surface of the roof of the newly formed blisters was composed of columnar or cuboidal epidermal cells. Their intercellular space was dilated. Most of the cells were degenerated and shed off into the blister fluid. The under-surface of the roof of the fully developed blisters was composed of flattened epidermal cells which were polygonal in shape. These findings suggest that the basal cells are degenerated and shed off into the blister fluid, so that the prickle cells become flattened and directly face the blister fluid during blister formation.

Lectin-binding pattern in extramammary Paget's disease by horseradish peroxidase (HRP)-labeling method--specific staining with Dolichos biflorus agglutinin (DBA).

Lectin-binding pattern in extramammary Paget's disease was studied using seven different lectins (Con A, WGA, RCA-I, PNA, SBA, DBA, and UEA-I) by means of the horseradish peroxidase (HRP)-labeling method. By light microscopy it was observed that Con A, WGA, RCA-I, and DBA stained almost all the extramammary Paget cells, while PNA, SBA, and UEA-I stained only some of them. Normal keratinocytes and tumor cells from other diseases such as mammary Paget's disease, malignant melanoma, squamous cell carcinoma, basal cell epithelioma, Bowen's disease, and seborrheic keratosis were positively stained with Con A, WGA, and RCA-I, but not with DBA except in some of the mammary Paget's cells. By electron microscopy it was observed that DBA stained the cell membrane and the Golgi apparatus of the extramammary Paget cells. The present results suggest that DBA is a specific lectin for glycoconjugates in extramammary Paget cells.

Distribution of glycoconjugates in normal human skin using biotinyl lectins and avidin-horseradish peroxidase.

Lectin binding patterns in normal human skin were studied using five different biotinyl lectins and avidin-horseradish peroxidase. The staining pattern was specific for each lectin. In the epidermis, peanut agglutinin (PNA) and soybean agglutinin (SBA) preferentially stained the cell membranes of keratinocytes in the spinous and granular cell layers, indicating changes in the saccharide residues during keratinocyte differentiation. In the secretory segment of an eccrine sweat gland, the superficial cells gave a strong granular staining with Ricinus communis agglutinin (RCA). Dolichos biflorus agglutinin (DBA) and SBA, on the other hand, strongly stained the basal cells. With these lectins, two types of cells in the secretory segment were clearly distinguished. These results show that (1) PNA and SBA binding sites increase during the course of keratinocyte differentiation, and (2) RCA, DBA, and SBA are good markers to distinguish two types of cells in the secretory segment of an eccrine sweat gland.