CD56⁺CD14⁺ cells spontaneously differentiate into enlarged DC-like cells with increased HLA-DR and CD86 expression. (A) Freshly isolated CD56⁺ cells were either immediately analyzed for scatter properties (using gate 4 shown in Figure 1) and HLA-DR as well as CD86 expression (day 0), or (B) CD56⁺ cells (10⁶/mL) were cultured in the absence of exogenous cytokines for 3 days and were then subjected to flow cytometric analysis. During short-term culture CD14⁺ cells with the appearance of intermediate-sized lymphocytes (top left) spontaneously differentiated into enlarged cells with FSC/SSC properties characteristic of DCs (top right) and (B) with strongly increased HLA-DR and CD86 expression. Data are representative of 3 independent experiments with different donors.