Expression of Sn on THP-1 cells and monocyte-derived macrophages.
Either whole blood, THP-1 cells, or monocyte-derived macrophages were labeled with the indicated mAbs followed by FITC-conjugated F(ab′)2 goat antimouse IgG. Monocytes were gated according to their characteristic forward and side scatter profiles following lysis of RBCs. Sn was expressed by THP-1 cells but was undetectable on the surface of monocytes. In comparison, the myeloid antigens CD14 and CD18 are expressed at high levels on both cell populations. Monocytes cultured for 6 days with autologous serum expressed only low levels of Sn, whereas addition of IFN-γ and TNF-α for 2 days of culture led to significant Sn expression. The data are representative of 2 to 3 experiments.
