Introduction: The current study investigates the Th1/Th2 cell cytokine expression in Wegener's Granulomatosis (WG) with the aim to establish whether a specific cytokine pattern exists.Materials and Methods: We produced and characterised T cells from nasal biopsies, bronchoalveolar lavage fluid and peripheral blood of patients with active systemic vasculitis (WG). We then analysed expression and secretion of IFN-gamma and IL-4 in these T cell populations by RT-PCR and ELISA.Results: We generated seven CD4+ T cell clones from nasal biopsy tissue which all produced IFN-gamma and no IL-4. In T cell clones derived from bronchoalveolar fluid, two clones secreted predominantly IFN-gamma and one clone predominantly IL-4. Further we also determined IFN-gamma and IL-4 secretion in sorted CD4+ and CD8+ T cell subsets isolated from eleven patients with WG, eight patients with systemic lupus erythematodes (SLE) and 10 healthy subjects following stimulation with PMA and MoAbs raised against CD3. Higher amounts of IFN-gamma were found in CD4+ and CD8+ T cells from WG patients when compared to healthy controls. With regard to the SLE patients there was a statistical increase in IL-4 secretion when compared to T cells from healthy donors or WG.Conclusion: These initial data demonstrate that mainly IFN-gamma is expressed in T cell clones from nasal biopsies and bronchoalveolar fluid of WG patients raising the possibility that a type 1 (Th1-like) profile of immune response predominates in WG.