FIG. 1.

ZPS increases surface expression of HLA-DR. Monocytes (4 × 10⁶ cells/ml in a 24-well plate) were incubated in culture medium with Sp1 (50 μg/ml), TT (2 LF/ml), or SEA (10 ng/ml) or in medium alone for different intervals ranging from 1 to 24 h. Surface expression of HLA-DR was then assessed by flow cytometry as described in Materials and Methods. The result shown is representative of three independent experiments with blood from different donors.