Lymphocyte blastogenesis to plaque antigens in human periodontal disease. I. Populations of varying severity of disease.

This study undertook to correlate lymphocyte transformation to human dental plaque antigens with clinical estimates of periodontal disease. Forty-eight patients with periodontal conditions ranging from normal gingivae to severe periodontitis were examined clinically. Oral cleanliness was determined by the Plaque Index System (Sflness & Loe 1964) and gingival health was assessed using the criteria of the Gingival Index System (Loe & Silness 1963). Pocket depth and loss of periodontal attachment from the cementoenamel junction (Ramfjord 1959, Glavind & Loe 1967) were also measured. Triplicate microcultures of peripheral blood lymphocytes were stimulated with four different concentrations of human plaque antigens. The uptake of 'H-thymidine during blastogenesis was measured by liquid scintillation counting. There was nO' correlation between the stimulation by most of the isolated plaque antigens or pooled plaque and the periodontal conditions as determined by plaque index, gingival index, pocket depth and loss of attachment. However, there was a significant, although low, correlation between clinical parameters and the stimulation of peripheral hlood lymphocytes hy B. melaninogenicus and A. viscosus. Stimulation with B. melaninogenicus correlated more highly with pocket depth and loss of attachment, while stimuiation with A. viscosus and A. naeslundii correlated more highly with plaque and gingivitis scores. The possible role of these organisms in the pathogenesis of periodontal disease involving cellular immunity was discussed as was the interpretation of data obtained in blastogenesis using peripheral blood lymphocytes and its relevance to the local phenomenon of delayed hypersensivity.