Specific lymphocytotoxic destruction of autologous epithelial cell targets in recurrent aphthous stomatitis

Concepts of the immunopathogenesis of recurrent aphthous stomatitis (RAS) based on lesion histology suggest an early role for CD4+ T cells. Other in vitro studies show enhanced destruction of epithelial targets by peripheral blood mononuclear cells (PBMC) from RAS subjects. The present project aimed to extend these studies under conditions simulating the in vivo situation. Epithelial cells were cultured and induced to express class I and class II major histocompatibility complex (MHC) antigens with gamma interferon (gamma-IFN). Co-cultures with autologous PBMC showed evidence of specific destruction of epithelial targets in RAS patients when compared with a control group. Co-culture with CD4+ enriched cells also showed specific epithelial cell lysis. Effector cells pre-incubated with interleukin-2 (IL-2) did not produce increased destruction of epithelial cells. This study has supported previous work and identified an early role of CD4+ cells.