Expression of CEACAM1 by immature and mature MDDCs.

<p><b><i>A)</i></b> The histograms show the log fluorescence intensity of CEACAM1 on the surface of immature and mature MDDCs labeled with either mouse anti-human CEACAM1-speciifc mAb D14HD11 (bold line profiles), or an isotype-matched control mAb (solid gray profiles), followed by fluorochrome-conjugated goat-anti-mouse secondary Ab. HeLa cells transfected with CEACAM1 cDNA (HeLa/cDNA) or empty plasmid vector (HeLa/Neo) were used as positive and negative staining controls of CEACAM1 expression, respectively. Peripheral CD14⁺ monocytes, CD19⁺ B cells, and C1R cells were also included for comparison of surface expression of CEACAM1 and expression phenotypes. The data show one representative staining from five healthy blood donors. <b><i>B)</i></b> Summarized data of CEACAM1 expression determined by flow cytometric analysis from five healthy blood donors. Fluorescence intensity was obtained from CEACAM-1 specific D14HD11 mAb staining subtracted from isotype-matched control mAb staining. The number shows the average fluorescence intensity. <b><i>C)</i></b> Western blot analysis of CEACAM1 protein expression. Equal amounts of protein extracts from peripheral CD19⁺ B cells, C1R cells, purified peripheral CD14⁺ monocytes, iMDDCs (harvested from day 7 cultures), and CD40LT-matured MDDCs were subjected to Western blot analysis using D14HD11 as a primary mAb and a secondary Ab labeled with HRP. The blot was reprobed with β-actin Ab as loading controls (lower panel). Data are representative for three independent experiments.