Establishment of human peripheral blood T-cell reactive with Porphyromonas gingivalis in severe periolontitis patients

Abstract

The aim of the study was to establish peripheral blood T-cell lines (TCLs) reactive with Porphyromonas gingivalis in severe adult periodontitis patients and also to investigate these cells in terms of their surface phenotypes, specificity and cytokine profiles. Peripheral blood mononuclear cells from 2 periodontitis subjects were activated by heat-killed whole cell P. gingivalis for 9 days and maintained subsequently through the cycle of 1 week rest in enriched medium and rIL-2, and 1 week stimulation with phytohaemagglutinin. The 2 TCLs reactive to P. gingivalis were established in culture up to 6-8 weeks. The specificity of each TCLs was assessed periodically by proliferation assay. Flow cytometric analysis of one TCL revealed approximately 65% CD4+ and 35% CD8+ cells, while the other TCL showed 15% CD4+ and 75% CD8+ cells. IL-4 and IFN-Y production by TCLs were measured with ELISA. Both TCLs reactive to P. gingivalis produced IFN-Y but none of IL-4, hence suggestive of a possible prominence of type 1 T-cells. The role of these cells for the immunopathogenesis of chronic inflammatory periodontal disease remained to be determined.