Differential Th1/Th2 balance in peripheral blood lymphocytes from patients suffering from flea bite-induced papular urticaria

BackgroundThe Th1/Th2 balance has not been characterized in patients suffering from flea bite-induced papular urticaria (FBPU). Our aim was to improve understanding of the immunopathogenesis of CD4+ and CD8+ T-cells in humans suffering from flea bite-induced papular urticaria.MethodsPeripheral blood mononuclear cells were obtained from 18 pediatric patients and 10 age-matched healthy controls. Cellular phenotypes, intracellular production of interferon gamma (IFNγ) and interleukin-4 (IL-4) in T-cells stimulated with polyclonal stimuli was determined by flow cytometry following short-term in vitro stimulation.ResultsThe results revealed lower frequencies of IFNγ-secreting (p = 0.02) and higher frequencies of IL-4-secreting (p = 0.03) CD4+ T-cells in patient lymphocyte cultures compared to healthy control cultures in the presence of polyclonal stimuli. This is the first description of differential cytokine patterns in papular urticaria patients.ConclusionPatients suffering from papular urticaria have an atopic status compared to healthy children.