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M T Rezende

Publications and source records attributed to M T Rezende.

4 recordsLinked to original sources
PubMed1988

In situ correlative immuno-identification of mononuclear infiltrates and invasive bacteria in diseased gingiva.

The purpose of this study was to identify and quantify mononuclear cells and invasive bacteria in consecutive histological sections in diseased gingiva. Gingival biopsies were obtained from sites displaying evidences of severe periodontitis (pocket depth greater than 5 mm, bleeding on probing) in six patients. Specimens were frozen and serially sectioned at 8 micron in a cryostat. Monoclonal antibodies (mAb) directed against membrane markers of mononuclear infiltrate cells and rabbit polyclonal sera against specific bacteria shown to be invasive in association with an immunoperoxidase technique and specific point quantification were used. The mAb panel included Leu 1 (Pan T), Leu 2a (T suppressor/cytotoxic), Leu 3a (T helper/inducer), Leu 6 (Langerhans/dendritic), Leu 7 (NK/K), Leu M3 (monocyte/macrophage), and B7 (B cell). This methodology allows for in situ per cent quantification of mononuclear cell subsets along with identification and quantification of invasive bacteria in the same gingival tissue site. This may be a practical approach to establish the relationship between bacterial invasion and cellular immune response by the host. This technique enabled the characterization of the mononuclear infiltrate in relationship to specifically identified invasive bacteria in diseased gingiva.

Actinobacillus↗
PubMed1987

Bacterial invasion in experimental gingivitis in man.

Gingival biopsies of the mesial papilla area of the first molar were obtained from each patient at 0-, 14- and 21-day intervals during plaque formation. The biopsies were fixed, serially sectioned, and Gram-stained. The incidence and distribution of the bacteria-like structures were studied by microscopy. In all the specimens the bacterial nature of Gram-stained material was substantiated. In the epithelium the highest number of bacteria was found at the outer layer of marginal oral epithelium, sulcular epithelium and apical oral epithelium along with a decreasing pattern of penetration progressing deeper into the layers of tissue. For junctional epithelium the situation was just the opposite. Each subject had significantly higher counts at Day 21 than at Day 14 for both epithelium and connective tissue. Also significantly higher counts were found in connective tissue compared with epithelium. The higher bacterial density of intragingival bacteria was associated with the higher gingival and plaque indices. This study suggests that early stages of gingival inflammation may be mediated by invasion of bacteria.

Bacteria↗
PubMed1987

The presence of bacteria in the oral epithelium in periodontal disease. III. Correlation with Langerhans cells.

Langerhans cells (LC) are cell types found in the skin and gingiva. LC have immunological functions as phagocytic cells and as antigen-presenting cells for T and B lymphocytes. Sections from biopsies of the gingiva in cases of periodontal disease were found to have increased numbers of LC. These biopsies also contained intragingival bacteria. Serial sections of frozen specimens of human gingiva were prepared for staining. Hematoxylin and eosin were used for tissue survey, the Gram stain for assessment of bacterial invasion, anti-Leu-6 monoclonal antibody associated with peroxidase technique (PAP) to identify LC, antibacterial sera to Bacteroides gingivalis and Actinobacillus actinomycetemcomitans associated with peroxidase to specifically identify these two common periodontopathogenic bacteria. Additional positive identification of bacteria was performed by preparing the same histological section containing gram-stained particles for scanning electron microscope and transmission electron microscope LC confirmation. The results suggest that the increased number of LC seen in diseased sites of oral epithelium containing intragingival microorganisms may be one of the host immune mechanisms to penetration by bacteria.

Antibodies, Monoclonal↗