Characterization of a mouse monoclonal antibody to vimentin by indirect immunofluorescence microscopy and immunoblotting.

A murine IgM monoclonal antibody, termed MC15A13G was produced after immunization of Balb/c mouse with Swiss mouse dental papillae. This antibody, characterized by immunoblotting analysis and indirect immunofluorescence microscopy, recognized a 57 Kda protein identified as vimentin in different cell types with no cross reaction with other cytoskeletal proteins.

Odontoblast differentiation and the formation of the odontoblast layer.

Origin, cell kinetics, and phenotypic aspects of odontoblast cell lineage are described. Epithelial-mesenchymal interactions regulate odontoblast differentiation. These interactions appear to be mediated by the extracellular matrix. Possible molecular mechanisms of cell-matrix interactions are discussed. Questions still unanswered are recommended for investigation.

The extracellular matrix of the dental pulp and dentin.

The dental pulp is a loose connective tissue, characterized by its specific anatomical location. Its extracellular components are obvious subjects for study, since such components are largely responsible for the physiological properties of the tissue. Several clinically important processes occur extracellularly, e.g., defense mechanisms such as inflammatory reactions and formation of calcified tissue. The dental mesenchyme has a crucial role during early tooth morphogenesis. The dental pulp, or rather the dental papilla, seems to have only an indirect role during dentinogenesis. This review discusses proteoglycans and glycosaminoglycans, fibronectin and other non-collagenous proteins, and the different types of collagen that have been studied in pulp connective tissue. With regard to its biochemical constituents, the pulp is similar to other loose connective tissues. Collagen type I is the major fibrous component, but collagen type III also constitutes a large portion. Fibronectin is present, as is a high content of proteoglycan. In the proteoglycans, all normally occurring connective tissue glycosaminoglycans can be demonstrated. The composition of the pulpal extracellular matrix during tooth development is quite different from that of the mature tooth. Thus, it is important not to draw any too-far-reaching conclusions about the situation in human pulp from results obtained by studying pulp from animal teeth with ongoing dentinogenesis. In spite of their common ancestry, pulp and dentin differ considerably in extracellular matrix composition. Proteoglycans and collagen type I are present in dentin. No type III collagen or fibronectin can be found in the dentin, although it is present in the dental pulp.(ABSTRACT TRUNCATED AT 250 WORDS)

An investigation of S-100 protein in embryonic dental papillae of rats.

We attempted to identify S-100 protein, a marker of neural crest tissue, within cells of the developing dental papillae of 18-day rat fetuses by means of the immunoperoxidase technique. Although there is experimental evidence that dental papillae are derived from neural crest, no marker protein was identified in this study.

Glycosaminoglycans in embryonic mouse teeth and the dissociated dental constituents.

The nature, amounts and distribution of glycosaminoglycans (GAG) before and during odontoblast terminal differentiation were studied. GAG have been isolated from intact mouse tooth germs and from dissociated dental epithelia and dental papillae after labeling with [3H]glucosamine or 35SO2-(4) asd precursor. The kinds and relative amounts of 3H-labeled GAG were analyzed by chromatography on a DEAE-cellulose column and cellulose thin-layer sheets. The amounts of individual GAG relative to total GAG were determined from the elution profiles, whereas their nature was identified by the selective removal of chromatographic peaks after enzymatic or chemical degradation. We found hyaluronate and probably a minute quantity of heparan sulfate in the dental epithelium, while hyaluronate, heparan sulfate, and chondroitin sulfate were the main types of GAG in the dental papilla. The chondroitin sulfate recovered was further fractionated by cellulose thin-layer chromatography into two isomers, namely chondroitin-2-sulfate (the major component) and chondroitin-6-sulfate. Changes in the elution profile from DEAE-cellulose chromatography of tooth GAG extracted from different developmental stages suggest that modifications of GAG occur during odontogenesis. Alcian blue staining localized large amounts of hyaluronate and sulfated GAG along the epithelio-mesenchymal junction. Tissue specificity and changing patterns of GAG were demonstrated during odontogenesis.

Mobility of concanavalin A receptors and distribution of cytoplasmic actin in odontogenic epithelial and mesenchymal cells.

The distribution of concanavalin A (Con A) surface receptors and cytoplasmic actin in the same cell was studied in monolayer cultures of 2 odontogenic epithelial cells of different developmental age and in ecto-mesenchymal cells derived from the same tooth germ. Con A receptors were demonstrated by fluorescein-isothiocyanate-labelled Con A (FITC-Con A) and cytoplasmic actin by a specific anti-actin autoantibody (AAA) traced with a rhodamine-labelled goat anti-human globulin (R-AHG). All 3 cell types, incubated with FITC-Con A at 37 degrees C for increasing time periods, showed progressive changes in staining patterns from clusters, caps to perinuclear globules. Capping was seen in the majority of immature epithelial cells at 120--180 min, in cells of more mature epithelium at 180--240 min and in ecto-mesenchymal cells at 240--360 min. Binding of FITC-Con A to cell surfaces resulted in sequential changes in AAA staining from filamentous to an aggregated or diffuse pattern, co-capping of aggregated or diffusely stained areas with those capped by FITC-Con A, presence of aggregated or diffusely stained areas in sites similar to the perinuclear globules stained by FITC-Con A, to final re-emergence of filamentous staining. Prior treatment of cells with cytochalasin B or colchicine promoted capping in epithelial but not in ecto-mesenchymal cells while presence of either drug throughout the staining procedure inhibited capping. The results show that Con A receptors are more mobile in epithelial compared to ecto-mesenchymal cells and in immature epithelial cells compared to their more mature counterparts, and that binding and mobility of Con A receptors on the cell surface is associated with redistribution of cytoplasmic actin. The cytochalasin B and colchicine experiments suggest that both microfilaments and microtubules may have synergistic roles in the opposing functions of receptor anchorage and mobility, and that the relative receptor immobility of ectomesenchymal compared to epithelial cells may be attributed to firmer receptor anchorage to the cytoskeleton.

[Morphometric studies in the dento-periodontal region under physiological conditions]. / Morphometrische Untersuchungen im dento-parodontalen Bereich unter physiologischen Bingungen

The morphometric method [6] has again proven reliable in the objective evaluation of clinical conditions of periodontal soft tissue even in longitudinal studies. In three-dimensional examination, criteria for the definition of the physiomorphological condition in the dento=gingival region could be established. The interdental region essentially determines the surface morphology of the interdental soft tissue. The interdental region was examined radiogically by using mehtods developed by the author and correlated with results of the evaluation in mesio-distal direction.