BACKGROUND: The aim of this study was to establish a culture method for mouse dendritic cells (DCs) in vitro and observe their morphology at different growth stages and their ability to induce the proliferation of T lymphocytes.

MATERIAL AND METHODS: Granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) were used in combination to induce differentiation of mouse bone marrow (BM) mononucleocytes into DCs. The derived DCs were then assessed for morphology, phenotype, and function.

RESULTS: The mouse BM-derived mononucleocytes had altered cell morphology 3 days after induction by GM-CSF and IL-4 and grew into colonies. Typical dendrites appeared 8 days after induction. Many mature DCs were generated, with typical dendritic morphology observed under scanning electron microscopy. Expression levels of CD11c, a specific marker of BM-derived DCs, and of co-stimulatory molecules such as CD40, CD80, CD86, and MHC-II were elevated in the mature DCs. Furthermore, the mature DCs displayed a strong potency in stimulating the proliferation of syngenic or allogenic T lymphocytes.

CONCLUSIONS: Mouse BM-derived mononucleocytes cultured in vitro can produce a large number of DCs, as well as immature DCs, in high purity. The described in vitro culture method lays a foundation for further investigations of anti-tumor vaccines.

Keywords: Bone Marrow Cells - ultrastructure, Cell Culture Techniques - methods, Cell Shape, Dendritic Cells - ultrastructure, Lymphocyte Activation - immunology, Lymphocyte Culture Test, Mixed, T-Lymphocytes - cytology, Time Factors