ASSOCIATION OF AMYLOID-P PROTEIN WITH PATHOLOGY IN PERIODONTAL TISSUES

The lesion of chronic periodontitis is characterized by the persistenc e of perivascular collections of degenerate plasma cells. In this stud y, immunohistochemical demonstration of amyloid P (AP) component was u sed to define the distribution of this protein in established periodon titis lesions and in biopsies of non-destructive marginal gingivitis. Quantitative assessment of AP indicated significantly higher levels in periodontitis than in gingivitis for all regions of the tissue. This was associated with pathology as determined by the intensity of plasma cell accumulation and the extent of connective tissue matrix degradat ion. AP was concentrated in the deep connective tissue areas but periv ascular accumulation was also noted, as was deposition associated with nerve bundles and, occasionally, in the extracellular matrix of the l ining epithelium. These findings have potential significance in relati on to the pathology of chronic periodontitis as AP has been shown to i nteract in a calcium-dependent manner with a number of ligands includi ng fibronectin, elastic fibres, C-4 binding protein and amyloid fibril s.