Stimulation of Lymphocytes in Vitro by Bacteroides intermedius and Bacteroides (Porphyromonas) gingivalis Sonicates

Abstract

The present study was designed to assess whether the in vitro stimulation of lymphocytes by sonicates of Bacteroides intermedius and Bacteroides (Porphyromonas) gingivalis is antigen specific or non‐specific. In addition, the role of T and B lymphocytes in these responses was assessed. Peripheral blood lymphocytes obtained from healthy volunteers were cultured in the presence of these bacterial preparations and the proliferative response was measured. In similar experiments the response of umbilical cord blood lymphocytes did not exceed background values. In limiting dilution experiments only 1:4000, 1:6800, and 1:8200 of the lymphocytes initially reacted to B. intermedius, which strongly argues for the antigen‐specificity of the response. Purified T cells, in the presence of monocytes, proliferated when stimulated with B. intermedius and B. gingivalis. As for B cell stimulation, the bacterial extracts were capable of inducing IgM production, which appeared to be T cell dependent. These findings support the notion that B. intermedius and B. gingivalis induce specific T cell activation; secondarily, a T cell dependent, polyclonal B cell activation may occur. J Periodontol 1990; 61:217– 223.

The role of the cell‐mediated immune response to Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in periodontitis

“…The frequency of the l? gingivalis-specific cells in periodontitis patients was found to be l in 12,000 in one study (124) and 1 in 6800 in another report (188). After periodontal therapy, the frequency of l?…”

Large-scale Early in vitro Response to Actinobacillus actinomycetemcomitans Suggests Superantigenic Activation of T-cells

“…Previous studies have provided evidence for antigen-specific (Raber-Durlacher et al, 1990;Mahanonda et al, 1991;Nakajima et al, 1999) as well as antigen-non-specific (Bick et al, 1981;Donaldson et al, 1982;Carpenter et al, 1984;Tew et al, 1989;Getka et al, 1996) mechanisms of response to periodontal pathogens. Local production of antibody reactive with non-oral antigens in gingiva has been presented as evidence for antigen-non-specific polyclonal activation of B-cells (Tew et al, 1989).…”

Antigen specificity and T‐cell clonality in periodontal disease

“…On the other hand, other investigators could neither confirm such a relationship nor demonstrate differences in the proliferative response between control subjects and the diseased patients. Raber‐Durlacher et al (158) reported that human umbilical blood lymphocytes, which can be regarded as an immunologically naïve population, showed a significant level of proliferation to polyclonal stimulants such as phytohemagglutinin and concanavalin A, but not to P. gingivalis . On the other hand, peripheral blood lymphocytes from healthy subjects proliferated in response to stimulation with Prevotella intermedia and P. gingivalis and the response was antigen specific (158).…”

“…Raber‐Durlacher et al (158) reported that human umbilical blood lymphocytes, which can be regarded as an immunologically naïve population, showed a significant level of proliferation to polyclonal stimulants such as phytohemagglutinin and concanavalin A, but not to P. gingivalis . On the other hand, peripheral blood lymphocytes from healthy subjects proliferated in response to stimulation with Prevotella intermedia and P. gingivalis and the response was antigen specific (158). These findings suggest that a P. gingivalis‐ specific immune response is generated in adult periodontitis.…”