Granulocyte‐macrophage colony‐stimulating factor induces a unique set of STAT factors in murine dendritic cells

摘要

AbstractCytokine‐mediated signaling pathways were studied in mouse dendritic cells (DC) by analysis of the activation pattern of STAT factors. Electrophoretic mobility shift assays were performed to detect STAT isoform‐specific complexes. Granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) simultaneously induced complexes containing STAT1, STAT3, STAT5A, STAT5B and STAT6. In non‐DC, a similar broad activation pattern of STAT factors by GM‐CSF or other cytokines has not been observed so far. By comparison, in peritoneal macrophages, GM‐CSF induced a complex with the properties of a truncated form of STAT5. Other cytokines tested on DC either failed to induce STAT factors [interleukin (IL)‐1β, IL‐2, IL‐15], or activated the same STAT factors as observed in peritoneal macrophages (IL‐4, IFN‐γ). Our results implicate a specific effect of GM‐CSF on STAT signaling in DC which might account for the cell type‐specific effect of this cytok