Phenotypic analysis of monocytes and MDDC.

PBMCs were isolated from fresh donor blood buffy coats. After an aggregation step, the cells were cultured with or without 25 ng/ml IL-4 and 50 ng/ml GM-CSF for 5 days to derive MDDC or monocytes, respectively. Expression of several cell surface markers was analyzed flow cytometrically with specific PE-labeled mAbs. Data represent mean % positive cells ± standard error of the mean (SEM) from 5 different donors. The expression level of each marker was compared between monocytes and MDDC and the corresponding p-value was calculated with a paired t-test.