LYMPHOCYTE SUBPOPULATIONS IN PERIODONTAL TISSUES

This project will evaluate the proportions and distributions of lymphocyte
subpopulations in human gingiva from sites displaying recent attachment
loss versus periodontal stability. Small interproximal gingival biopsies
will be obtained from three sites in each of 30 patients: 1) site
demonstrating at least 2 mm clinical attachment loss during the previous 3
months; 2) similar site which has shown no recent attachment loss; and 3)
healthy site with minimal pocket depth. Serial frozen sections will be
prepared and commercially available monoclonal antibodies used to identify
surface markers on T, T helper/inducer, T suppressor/cytotoxic, B, and on
activated (IL 2 receptor) T and B lymphocytes. Cells will be labeled
using an avidin-biotin-peroxidase (ABC) system. Double-labeling
experiments will identify subpopulation and activation markers present on
the same lymphocyte. Peripheral blood lymphocytes from each patient will
also be tested with the above antibodies (fluorescent labels) for
comparison. Description of lymphocyte subtypes, activation, and their distribution
relative to an active periodontal pocket is important information in
assessing the role of the immune response in periodontal attachment loss.
In addition, unique immunologic characteristics may become evident and may
be used to identify the active periodontal lesion. Long-term objectives
include combining the above technology with identification of purified
bacterial antigens in tissue using monoclonal or monospecific antibodies.
This would allow for comparative mapping to identify specific
antigen/lymphocyte interactions in situ in various stages of periodontal
disease. These histologic probes would be used in the description of the
immunopathogenesis of periodontal disease and to identify deagnostic
markers of active periodontitis.