To explore the role of IL2-GMCSF in the cell interaction, we firstly evaluated the expression of the IL-2 receptor (IL-2R) and the GM-CSF receptor (GM-CSFR) in different cells using qRT-PCR, including C57BL/6 mouse splenocytes, melanoma cell lines B16F10 and B16-GMCSF, an immature DC cell line DC2.4 [39], a T cell hybridoma A1.1, a macrophage cell line RAW264.7 and a myelomonocytic leukemia cell line WEHI-3. Here, CSF2 is linked to melanoma.