[In vitro amplification and identification of immature dendritic cells from murine bone marrow].

OBJECTIVE: To establish a method for in vitro amplification of immature dendritic cells from murine bone marrow, and to identify it with morphological, immunological phenotype determination, and functional examination. METHODS: Dendritic cells from murine bone marrow were cultured with different dosage of rmGM-CSF. The suspending cells were examined with scanning electronic microscope, and the non-sensitized T lymphocyte proliferation was observed by mixed lymphocyte reaction. RESULTS: Dendritic cells (DC) cultured in lower dosage of rmGM-CSF (Gm(low)DC) exhibited typical characteristics of DCs with high expression of CD11c and low expression of CD40 and I-A/I-E, and non-expression of B7-1 on the surface of the cells. The capacity of Gm(low)DC to stimulate the proliferation of non-sensitized T lymphocyte in vitro was weaker than that of Gm(high)DC. CONCLUSION: Gm(low)DC exhibited typical characteristics of DC, immature in cell phenotype and cell functions, suggesting that our methods of immature DCs culturing was feasible. The dosage of rm GM-CSF has direct relationship with the maturation degree of DC. Generally speaking, mature DC was mainly induced by high dosage of rmGM-CSF, while immature DC by low dosage.