Characterization of human monocyte-derived macrophages which were alternatively activated in the presence of IL-4 and allergen. A, Surface marker expression of HLA-DR and CD86 measured by flow cytometry after 48 h of polarization as mean fluorescence intensity (MFI). B, mRNA expression of M2 markers measured by RT-PCR as fold induction compared with control macrophages. Bars indicate mean values; data were analyzed with one way ANOVA (n = 5). **P < .01, and *** P < .001.