[The biological characteristics of peripheral blood CD123+ myeloid dendritic cell].

AIM

To investigate the biological characteristics of CD123(+)DC derived from cord blood monocytes in myeloid culture system.

METHODS

The monocytes isolated from peripheral blood were cultured with GM-CSF and IL-4 to induce DC for 7 days, and the related phenotype of DC was analyzed by flow cytometery. CD123(+)DC were purified with magnetic cell sorting separation technique. The morphological properties of CD123(+)DC was observed under confocal laser-scanning microscope and scan electron microscope. The concentration of IL-12 secreted by DC was analyzed by ELISA. The function of endocytosis and antigen presentation was evaluated by uptaking FITC-dextran and allogeneic mixed T lymphocyte reaction (MLR).

RESULTS

FACS analysis showed the high expression of CD86 and CD11C, moderate expression of CD1a and CD123, low levels of CD83 on DC after induction by GM-CSF and IL-4 for 7 days, while the expression of CD304 was rather low. Well-distributed CD123 and CD11C were detected on DC. Purified CD123(+)DC showed typical morphology of immature DC with similar short cytoplasmic projections as CD123(-)DC. CD123(+)DC secreted lower level of IL-12, and exhibited more significant endocytosis and less antigen presentation function than that of CD123(-)DC(P<0.05).

CONCLUSION

CD123(+)DC induced with GM-CSF and IL-4 might be more early phase of immature myeloid DC along with the DC differentiation, with special biological characteristics.