B-lymphocyte blastogenesis in response to periodontitis-associated bacteria. Kinetics and proportion of total...

A role for activated B-lymphocytes in mediating the initiation and/or progression of periodontal diseases has been proposed in previous work. The present study was conducted to: (1) assess the proportion of total lymphocyte blastogenic response to selected oral bacteria which is composed of T-cell and B-cell activation, respectively, and (2) to determine whether different kinetic patterns exist for the T-cell vs. the B-cell responses to these bacteria. Using lymphocyte rosetting and culturing techniques, rosette-positive and rosette-negative lymphocyte preparations were examined for blastogenic responsiveness following stimulation with a variety of both Gram-positive and Gram-negative periodontitis-associated bacteria. Results of these studies indicated that both peripheral blood lymphocytes (PBL) from healthy adults and cord blood lymphocytes (CBL) from placental afterbirths responded to these bacteria with similar kinetic patterns. The net PBL blastogenic response appeared to consist of an early B-cell response, which peaked at Days 2 or 3 of culture, followed by a later T-cell response, which peaked at Days 5 to 6 of culture. The B-cell response appeared to be T-cell-dependent in that B-cells cultured alone showed minimal thymidine uptake over the entire 6-day period, but the addition of irradiated T-cells to these B-cell cultures resulted in a greatly enhanced B-cell response.