Abstrakt: |
The present study was designedto assess whether the in vitro stimulation of lymphocytes by sonicates of Bacteroides intermediusand Bacteroides (Porphyromonas) gingivalisis 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. intermediusand 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. intermediusand B. gingivalisinduce specific T cell activation; secondarily, a T cell dependent, polyclonal B cell activation may occur. J Periodontol 1990; 61:217– 223. |