High amounts of circulating interleukin (IL)‐6 in the form of monomeric immune complexes during anti‐IL‐6 therapy. Towards a new methodology for measuring overall cytokine production in humanin vivo

摘要

AbstractA patient with plasma cell leukemia was treated with anti‐interleukin (IL)‐6 monoclonal antibodies (mAb) for 2 months. Using chromatography on protein A‐Sepharose, anti‐murine‐IgG‐Sepharose, anti‐IL‐6‐mAb‐Sepharose and gel filtration at pH 2.3, we have demonstrated that the anti‐IL‐6 mAb, by preventing the binding of IL‐6 to its cell membrane receptor and its renal elimination, has induced huge amounts of IL‐6 to circulate in the form of monomeric immune complexes. By using this observation, we have developed a mathematical modelling that allows the determination of the overall daily production of IL‐6 in this patient, which was in the range of 15 μg per day. Overallin vivoproduction of cytokines has never been evaluated