Cytokine induction of a human acute myelogenous leukemia cell line (KG-1) to a CD1a(+) dendritic cell phenotype

Dendritic cells (DC) are highly specialized antigen-presenting cells locate d in many nonlymphoid tissues, and Langerhans cells (LC), a specialized for m of DC, are found in the skin. LC as antigen-presenting cells play a criti cal role in the induction of allergic contact dermatitis, LC research is di fficult because few LCs can be isolated from human skin, so efforts have fo cused on obtaining DCs from alternative sources. Mononuclear cells from per ipheral blood and CD34(+) stem cells from human cord blood and marrow can b e induced to form phenotypic and functional DCs, but experiments of this ty pe are expensive and the DC yield is low. We report here the induction of t he myeloid leukemia cell line (KG-1) to a DC morphology and phenotype by cu lturing the cells in a defined cytokine cocktail, Morphologically, the KG-1 -derived DCs are large irregularly shaped cells with prominent dendritic pr ocesses and hair-like cytoplasmic projections, Phenotypically, the KG-1-der ived DCs lack lineage-specific markers, and express MHC class II, costimula tory molecules CD80 and CD86, and CD83, Functionally, KG-1-derived DCs are capable of phagocytosing latex microspheres and are able to induce a potent allogeneic T-cell response. Within the KG-1-derived DCs, a subpopulation m aintains the DC phenotype and morphology described above but further develo ps CD1a(+) marker expression similar to that of resident skin-derived LCs, These findings illustrate that phenotypic, morphologic andfunctional DCs ca n be derived from the KG-1 cell line.