Pamidronate infusion in patients with systemic sclerosis results in changes in blood mononuclear cell cytokine profiles

Summary A single infusion of pamidronate was given to patients with systemic sclerosis (scleroderma, SSc) to assess effects on cytokine production by peripheral blood mononuclear cells (PBMC) and lymphocyte subsets. Eighteen patients with SSc received a single intravenous dose of 60 mg of pamidronate and were followed for 6 months. Assessment of cytokine production [interferon (IFN)-γ, interleukin (IL)-10, transforming growth factor (TGF)-β1, tumour necrosis factor (TNF)-α and IL-4] by PBMC and lymphocyte subsets by flow cytometry was carried out before and after the pamidronate infusion. Unstimulated PBMC produced increased amounts of IFN-γ and TNF-α and reduced levels of TGF-β1 for up to 24 weeks after the infusion. γδ T cells from patients with SSc were activated in vitro and produced increased IFN-γ. The effects of pamidronate on modulation of cytokine profiles in patients with SSc may merit future study.