Immunohistochemical localization of chondroitin sulfate and dermatan sulfate proteoglycan in human gingival connective tissue

This study investigated the immunohistochemical localization of chondroitin sulfate (chondroitin, 4-sulfate and 6-sulfate) and dermatan sulfate proteoglycan (PG) in human gingival connective tissue, using monoclonal antibodies. Dermatan sulfate was found to be widespread in connective tissue, with an especially strong response shown in collagen fiber bundles under the epithelial basement membrane. Chondroitin 4-sulfate occurred widely in connective tissue but showed only a weak response. Chondroitin 6-sulfate was located in peripheral blood vessels. Chondroitin was not detected in gingival connective tissue.     

Elastic and oxytalan fibres in normal and inflamed dog gingivae

Consecutive sections of normal and inflamed dog gingivae were stained for elastic and oxytalan fibres using Victoria blue and aldehyde fuchisin with and without prior oxidation in potassium monopersulphate. Elastic fibres were present beneath the oral epithelium but absent beneath the junctional epithelium. Fibres stainable after oxidation were related particularly to the basement membrane regions of the oral and junctional epithelia and small blood vessels and persisted in inflammatory lesions. It is suggested that there is a different distribution of elastic and oxytalan fibres in free gingivae and that the latter may help stabilise blood vessels and the epithelial attachment under functional pressures.     

Immunohistochemical study of chondroitin sulfate and dermatan sulfate proteoglycan in dental pulp and dentin

We investigated the localization of chondroitin sulfate and dermatan sulfate proteoglycans in the dental pulp and dentin of rats, using a combination of an immunohistochemical technique coupled with specific enzymatic digestion. Chondroitin 4-sulfate and dermatan sulfate were found to be widespread in pulpal connective tissue, predentin and dentinal tubules. The response to predentin was found to be particularly strong. Chondroitin 6-sulfate was stretched in pulpal connective tissue and predentin, but showed only a weak response.     

Langerhans cells in oral epithelium of chronically inflamed human gingivae

This study describes the histopathological features and the distribution of oral epithelial Langerhans cells in 19 gingival biopsies originating from an adult Tanzanian population characterized by very poor oral hygiene and severe gingival inflammation. Light-microscopically, all biopsies contained often large inflammatory connective tissue infiltrates, 6 of which predominantly contained plasma cells while the rest were dominated by lymphocytes. Seven specimens contained peculiar accumulations of round lymphoid and dendritic cells in the lower cell layers of the oral epithelium. These phenomena have not previously been demonstrated in human gingiva and deserve further attention in studies on the pathogenesis of periodontal diseases. Immuno-histochemical staining with OKT6, OKT4 and OKT8 antibodies showed markedly increased numbers of OKT6-positive cells in 7 specimens and clusters of OKT4- and OKT8-positive cells in the oral epithelium of 4 specimens. High numbers of OKT6-positive cells were not related to the presence of intra-epithelial, non-keratinocyte infiltrates or large connective tissue infiltrates. The variable numbers of oral epithelial Langerhans cells may therefore result from different bacterial antigens elucidating different responses or, alternatively, reflect different responses to similar plaque antigens penetrating the surface of the oral epithelium.     

Microcirculation and micromorphology of healthy and inflamed gingivae

Inflammation changes the microcirculatory and micromorphological dynamics of human gingiva. Laser Doppler flowmetry (LDF) and a replica technique for scanning electron microscopy (SEM) were used to examine the facial soft tissues of six maxillary anterior teeth, before and after treatment, in 12 patients exhibiting clinically healthy tissues and in 12 others with moderate gingivitis. All patients received oral hygiene instructions and scaling. The gingiva in the gingivitis group became healthy within 3 months after treatment. LDF results were recorded at the free gingivae, interdental gingivae, attached gingivae, and alveolar mucosae of the six maxillary anterior teeth. The gingival blood flows in the gingivitis group before treatment were significantly different from those in the healthy gingiva group. Flows were restored to the same level as the healthy gingiva, with no significant difference, at P 0.01, 3 months after treatment. However, there were significant differences among sites during the same period. In addition, blood flow was reduced to a normal level after the inflammation subsided. Initially, the gingival morphology of the inflamed sites exhibited irregular free gingival margins, in contrast to that of healthy gingivae, which were characterized by rounded margins closely adapted to the tooth. One month post-treatment, the gingivae exhibited a wrinkled appearance, but they had reverted to normal micromorphology by 3 months post-treatment. The replica impression technique can be used to record gingival micromorphology both before and after reduction of inflammation.     

Immune components in normal and inflamed human dental pulp.

Normal and inflamed human pulpal tissues were examined for the presence of humoral immune components. The results indicate that normal pulpal tissue is essentially devoid of components necessary for localized immunoglobulin synthesis as shown by the absence of any immunoglobulin-containing cells (ICC). Tissue fluorescence was observed only in the unwashed samples and mainly with the fluoresceinated IgG reagent. This fluorescence was essentially eliminated by prewashing prior to the application of the fluoresceinated antiserums. On the other hand, inflamed pulpal tissues showed the presence of various ICC. IgG ICC were preponderant, constituting more than 60 per cent of ICC observed. Significant numbers of IgA and IgE ICC were also observed in each sample examined; whereas IgM ICC were present in only 3 of 12 specimens. At the tissue level, fluorescence was observed both in unwashed and prewashed tissues, predominantly with the labelled IgG antiserum. The presence of ICC, as well as extracellular immunoglobulin in inflamed pulpal tissue suggests that the potential exists for immune mechanisms to contribute to the pathological periapical changes seen as sequelae to pulpal inflammation.     

Presence of leukocytes in crevices of healthy and chronically inflamed gingivae

The presence of leukocytes within the crevices of clinically healthy and chronically inflamed gingivae has been studied in human and dog. Cellular samples were obtained from the gingival crevices by the "Styroflex" technique. The area on the styroflex film showing the presence of leukocytes was determined and a differential count of the cells performed. Biopsies were also taken from dogs with clinically healthy gingivae.
Neutrophils, lymphocytes and monocytes were regularly found in samples from clinically healthy gingivae even when histological sections failed to show any inflammatory infiltrates in the gingival connective tissue. The differential counts showed 95–97 % neutrophils, 1–2 % lymphocytes and 2–3 % monocytes. Increased numbers of leukocytes were found in the crevices of chronically inflamed gingivae. However, the proportions of the various leukocytes were the same as those found in the crevices of clinically healthy gingivae. The results of the present investigation support the view that only quantitative differences exist between clinically healthy and chronically inflamed gingivae.     

Electron microscopy of acid phosphatase in the exudate from inflamed gingivae

An ultrastructural study on human gingival fluid made it possible to localize acid phosphatase in polymorphonuclear leucocytes, bacteria and to a lesser degree in histiocytes. The polymorphonuclear leucocytes with autophagic bodies, and the histocytes contained intact and ruptured lysosomes as well as phagocytic vacuoles with engulfed bacteria. The surface of leucocyte cell membranes sometimes presented a positive enzymatic reaction. Large bodies, rich in acid phosphatase were observed in mast cells. In the epithelial cells scattered fine lead precipitates were noted and the epithelial nuclei sometimes reacted positively. In Gram positive bacteria, acid phosphatase was localized between the cytoplasmic membrane and the cell wall, whereas in Gram negative bacteria a positive reaction was observed in the outer layers of the cell wall. Bacteria without cell walls were surrounded by a lead precipitate. In addition, lead stainings were located in the bacterial cytoplasm. The major acid phosphatase activity seemed to be related to the leucocytes and the micro-organisms.     

Localization of chondroitin sulphate and dermatan sulphate in human dental pulps — an immunohistochemical study

The distribution of dermatan sulphate and chondroitin sulphate in human dental pulps has been assessed using monoclonal antibodies and immunoperoxidase localization techniques. The pulpal tissues were reacted with specific antibodies following pretreatment of the sections with chondroitinase ACII or chondroitinase ABC. Both the 4- and 6-sulphated isomers of chondroitin sulphate were detected in the tissues studied. Very little derrmatan sulphate could be detected. These glycosaminoglycans appeared throughout the pulpal connective tissues with a particularly strong localization to the region adjacent to the odontoblastic and predentine layers. Such distribution strongly implicates chondroitin sulphate in the mineralization process of human dentine.     

Copper-zinc superoxide dismutase activity in normal and inflamed human dental pulp tissue.

Information regarding the presence of the free radical scavenging (inactivating, dismutating) enzyme superoxide dismutase in human dental pulp was sought. Free radicals, such as the superoxide anion radical (O2-) and the hydroxyl anion radical (OH.), are powerful biological oxidants produced by phagocytes during the normal tissue response to injury and infection. Also produced is hydrogen peroxide (H2O2), an aggressive oxygen species formed by the reaction of superoxide with itself, i.e., a dismutation in which one molecule of O2- is oxidized by the other. These three reactive oxygen intermediates serve as part of the normal host biological defense mechanism for the inactivation of microorganisms and the breakdown of their toxic products. Both normal and inflamed dental pulps were assayed for the presence of this enzyme. Superoxide dismutase activity was identified in the normal pulpal tissues. There was a slight decrease in activity with age. In the inflamed pulpal tissues, enzyme activity was markedly and significantly increased in comparison to that in the normal tissues. These observations indicate that human dental pulp possesses an endogenous defense mechanism designed to protect the tissue components (cells and matrix) from the toxic effects of the reactive oxygen intermediates. In this regard, the inflammatory response of this specialized and somewhat isolated (compartmentalized) tissue is not unlike that seen in other connective tissues.     

成人正常、炎症牙髓组织匀浆中IL-8含量的测定

目的:研究成人正常、炎症牙髓组织中IL-8(Interleuk in-8)的含量,同时探讨IL-8在牙髓炎症机制中的作用和意义。方法:采用ELISA法分别对成人正常、慢性牙髓炎、急性牙髓炎牙髓组织中IL-8的含量进行测定。结果:3组成人牙髓标本中均能检测到IL-8,其中正常组IL-8含量最低,为0.0026±0.0011 ng/mg;慢性牙髓炎组IL-8的含量升高为0.0120±0.0032 ng/mg;而急性牙髓炎组IL-8含量最高,为0.0224±0.0097 ng/mg;各组间均有显著性差异。结论:成人炎症牙髓组织中IL-8的含量高于正常牙髓,IL-8可能参与并调节成人牙髓炎的病理形成过程。     

Lactate dehydrogenase (LDH) isoenzyme pattern in normal and inflamed human dental pulp.

Enzyme variants may serve an adaptive role in providing the correct vectorial properties for the metabolism of a tissue, or broadening its environmental tolerance range. To determine if the LDH isoenzyme pattern of human dental pulp changes during inflammation, supernatants from normal and inflamed dental pulp homogenates were separated by polyacrylamide gel electrophoresis. Inflamed pulps had a higher M subunit content and a markedly increased enzyme activity. These results might reflect adaptive changes at the enzyme level associated with a partial shift towards anaerobic metabolism during inflammation of the pulp.