Up-regulation of costimulatory molecules in clinical AML samples.

(A) Thirty clinically isolated AML cells were incubated with SB for 48 hours to detect the altered expression of CD80, CD86, HLA-DR, HLA-ABC, and ICAM-1 by flow cytometry. Relative fluorescence intensity of medium-treated (SB⁻) and SB-treated (SB⁺) cells are shown as open and closed circles, respectively. Statistical significance of each expression between medium-treated and SB-treated samples was analyzed by the Wilcoxon rank sum test, and P is shown. (B) Four of 30 samples exhibited more than a 3-fold increase in the expression (MFI) of CD86. The data of 3 of these 4 samples (UPN 8133, 8576, and 8646) are shown as the highest responders.