Human CD141 dendritic cells generated from adult peripheral blood monocytes.

Human CD141 dendritic cells (DCs), specialized for cross-presentation, have been extensively studied in the development of DC-based therapy against cancer. A series of attempts was made to generate CD141 DCs from cord blood CD34 hematopoietic progenitors to overcome the practical limitation of in vivo rareness. In the present study, we identified a culture system that generates high CD141 DCs. After culture of CD14 monocytes in the presence of granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-4 for 8 days, CD141 was detected on cells that adhered to the bottom of the culture plate. The attached cells exhibited typical features of immature monocyte-derived DCs (moDCs), except for higher CD86 expression, more dendrites and higher granularity compared with those that did not attach. With 3 additional days of culture, increased CD141 expression on the cells was retained along with adhesion ability and partial expression of CLEC9A, a c-type lectin receptor. Furthermore, the cells exhibited effective uptake of dead cells. Interestingly, the attached moDCs differently responded to polyinosinic:polycytidylic acid (poly I:C) stimulation as well as a mixed lymphocyte reaction. Collectively, our findings show that human CD141 DCs can be sufficiently generated from peripheral blood CD14 monocytes, potentiating further investigation into generation of higher yields of cross-priming human DCs in vitro.