Background: Peripheral blood CD8+ T cells expressing interferon gamma and interleukin-4 (IL-4), and lacking CD28 molecules, were responsible for the dynamic interplay between peripheral blood and inflammatory sites.
Introduction: The aim of the current study was to define in Behçet's disease (BD), CD8+ T-cell subsets using CD28 and CD11b monoclonal antibodies, and the characterization of the Tc1/Tc2 ratio and perforin expression.
Methods: Flow cytometry was used for intracytoplasmic cytokines and perforin expression. Effector cells were investigated by adhesion of CD8+ T cells to human microvascular endothelial cells and by chemotaxis using beta-chemokine.
Results: Interferon-gamma-producing CD8+ T cells in active and remission BD patients were increased, which induce a significant increase of the Tc1:Tc2 ratio in BD. CD8(+)CD28(-)CD11b+ T cells were found to be more expanded in BD patients than in age-matched healthy controls. The expression of CD11b molecules in active BD allowed to CD8(+)CD28+/CD8(+)CD28- subsets to adhere to human microvascular endothelial cells, with more efficiency in BD. Using MIP-1alpha, we observed that the migratory process of CD28(-)CD11b(+) is more important in BD. CD28(-)CD11b+ exhibited an increased perforin expression in BD patients.
Conclusion: Taken together these results suggest the presence of immune activation, probably in response to a profound inflammation affecting BD patients. The physiopathological significance of these results were toward autoimmune diseases and/or infectious process.