DC acquisition of allogeneic HLA class I molecules.

DCs from (A) HLA-A2–negative or (B) HLA-DR*0101–negative individuals were cultivated on a monolayer of nonirradiated melanoma cells expressing the HLA-A2 or the HLA-DR*0101 allele, respectively (right panels). As a control, DCs were cocultured with HLA-unrelated melanoma cells (left panels). After 20 hours of cocultivation, the expression of the allogeneic HLA molecules on the cell surface of DC populations was analyzed by flow cytometry using mAbs specific for CD83 and (A) HLA-A2 or (B) DR0101 molecules.