Flow cytometric analysis of different adhesion molecules expression on circulating CD14(-) and CB64(-) human dendritic cell precursors

Blood dendritic cell precursors (DCps) are identified as mononuclear leukoc ytes expressing HLA-DR but lacking the characteristic antigens associated w ith T cells (CD3), NK cells (CD16 and CD56) and B cells (CD19). Dendritic c ell precursors are distinguished from monocytes by their lack of expression of CD64 rather than of CD14. This study investigated whether CD14(-) DCps differed from CD64(-)DCps, which were predominantly CD14(+), in their expre ssion of five well-characterised adhesion molecules. There were significant ly fewer cells expressing CD11b, CD18 and CD29 in the CD64(-)DCp population compared with CD14(-) DCps, and this CD64(-) DCp subpopulation also had a lower expression of CD11b and CD18. Our results suggest that the two DC pre cursor subpopulations may differ from one another in their binding characte ristics to blood vessel walls and to other leukocytes.