It is disputed to what extent tumor necrosis factor-alpha is present in the thyroid follicular epithelial cells and/or in the interstitial cells in different disorders of the thyroid gland. We describe the immunohistochemical detection of tumor necrosis factor-alpha using formaldehyde fixed and paraffin embedded tissue and a polyclonal anti-serum with high tumor necrosis factor-alpha neutralising activity. We examined the distribution of tumor necrosis factor-alpha in interstitial cells and follicular epithelial cells in thyroid carcinomas, adenomas, non-toxic multinodular goiters and autoimmune thyroid diseases. Tumor necrosis factor-alpha was demonstrated in thyroid follicular epithelial cells, most frequently in non-toxic multinodular goiters (six of seven patients) and less frequently in adenomas (three of nine patients), papillary carcinomas (two of five patients), follicular carcinomas (one of five patients), Hashimoto's disease (one of six patients) and Grave's disease (one of seven patients). Tumor necrosis factor-alpha producing interstitial cells were found in two thirds of patients with all six thyroid diseases.

The immunohistochemical localization of heparan sulphate, collagen type I, III and IV, laminin, tenascin, plasma- and cellular fibronectin was studied in tooth germs from human fetuses. The lamina basalis ameloblastica or membrana preformativa, which separates the pre-ameloblasts from the pre-dentin and dentin, contained heparan sulphate, collagen type IV, laminin and fibronectin. Enamel reacted with antifibronectin, but the reaction varied depending on the type of fibronectin and the source of antibody. In early pre-dentin, collagen type I, laminin, tenascin and fibronectin were present. In late pre-dentin and dentin collagen type I was found in intertubular dentin and in the zone between enamel and dentin. The close relationship between collagen type I in dentin and fibronectin in immature enamel is interesting, as it may contribute to the stabilization of the amelodentinal interface. In dental pulp, collagen type IV and laminin were found in the endothelial basement membranes. Collagen type I and III, tenascin and fibronectin were localized to the mesenchymal intercellular matrix. The results of this study have supported the assumption that the lamina basalis ameloblastica is a basement membrane, and have lead to the suggestion that ameloblasts are producers of fibronectin or a fibronectin-like substance.

We describe the distribution of interleukin-6 and interleukin-1 alpha in thyroid tissues obtained from patients with autoimmune diseases or neoplastic thyroid disorders employing immunohistochemistry in sections from paraffin embedded tissue blocks. Interleukin-6 was found in thyroid follicular epithelial cells (TFEC) from papillary carcinomas (four of five patients) but not in follicular carcinomas (five patients). Interleukin-6 was also detected in non-toxic multinodular goiters (four of seven patients), in patients with Graves' disease who did not have an early recurrence of hyperthyroidism after surgery (three of four patients), in follicular adenomas (five of nine patients), in Hashimoto's thyroiditis (two out of six patients, both belonging to a group of three with an early stage of the disease), and in paraadenomatous tissues (in three of nine patients). Interleukin-1 alpha positive TFEC were found less frequently than interleukin-6, and only in tissues with interleukin-6 positive TFEC. Only few interleukin-6 and interleukin-1 alpha positive interstitial cells were found, even in the lymphocyte infiltrates (in both the autoimmune, benign or malignant disorders). In conclusion, both interleukin-6 and interleukin-1 alpha could be demonstrated in TFEC from patients with autoimmune diseases, benign neoplasms or papillary carcinoma, whereas follicular cancer tissues were without interleukin-6 and interleukin-1 alpha. In contrast with previous studies, interleukin-6 and interleukin-1 alpha were demonstrated in TFEC from patients with both Graves' disease and Hashimoto's thyroiditis, and the presence of these cytokines was related to the stage of the autoimmune process.

The primary aim of the present study was a localization of hyaluronan (HA) in human deciduous tooth germs in the bell stage. HA was compared to the content of chondroitin sulfates (CSs). HA was detected with a biotin-labeled HA-binding protein (HABP) and CS with a monoclonal antibody. As controls, enzyme digestions were carried out. Furthermore, the glycosaminoglycans were investigated histochemically with enzyme digestions followed by alcian blue staining. The investigation showed a considerable content of HA in the stellate reticulum, although CS was also found, primarily when treatment with protease was omitted. The dental papilla contained both HA and CS, while the predentin and the dentin contained only CS. The enamel did not contain any CS, but some staining with HABP was observed along the borderline between the ameloblasts and the enamel. The significance of HA in the stellate reticulum is discussed. The importance of carrying out investigations with and without protease digestions is stressed.

A quantitative immunocytochemical method is described for measuring intracellular thyroglobulin in human thyrocytes grown in monolayer, based on the imidazole-enhanced 3,3'-diaminobenzidine/peroxidase reaction. The influence of ten different fixatives on the content of thyroglobulin immobilized on nitrocellulose filters and in single cells and the influence of thyrotropin and interleukin-1 beta (IL-1 beta) on the amount of intracellular thyroglobulin were evaluated. The most suitable fixatives for single cells were 2% carbodiimide, Lison's 'Gendre fluid' and 2 or 4% paraformaldehyde, whereas Bouin, Carnoy A and B, formalin-calcium and Lillie's formaldehyde-acetic acid-alcohol fixative all resulted in reduction of intracellular thyroglobulin. Two per cent glutaraldehyde caused a considerable reduction (p less than 0.0001). Nitrocellulose filters were not suitable for evaluation of the fixatives, since the results did not correspond to those obtained with single cells. Thyrotropin (1 U/l) increased intracellular thyroglobulin, whereas addition of interleukin-1 beta to the culture medium for three days caused a dose-dependent reduction with a plateau level at 2 x 10(-6) gl-1 (10(4) U/l) of interleukin-1 beta. It is concluded that changes in intracellular thyroglobulin concentration caused by either thyrotropin or IL-1 beta can be quantified under experimental circumstances where samples for measurements of thyroglobulin-mRNA or extracellular thyroglobulin are difficult or impossible to obtain.