Interleukin-4 affects the mature phenotype and function of rat bone marrow-derived dendritic cells.

Granulocyte macrophage‑colony stimulating factor (GM‑CSF), and GM‑CSF plus interleukin‑4 (GM‑CSF + IL‑4) are two commonly‑used cytokine therapies for the generation of bone marrow‑derived dendritic cells (DCs). However, the mechanisms underlying IL‑4 involvement in DC generation and maturation remain unclear. In order to investigate the effect of IL‑4 on DC generation, DCs from rat bone marrow progenitors were generated using GM‑CSF, with and without IL‑4. GM‑CSF + IL‑4 DCs exhibited more mature phenotypes, and the levels of naïve allogeneic T cell stimulation were greater compared with GM‑CSF DCs. Phosphorylated signal transducer and activator of transcription 6 (p‑STAT6), the active form of STAT6, was expressed in GM‑CSF + IL‑4 DCs but not in GM‑CSF DCs. The present study demonstrated that IL‑4 influences DC morphology and immune function, and that this process may be associated with the activation of STAT6.