Background information
CD304 (BDCA-4/Neuropilin-1)1 is specifically expressed by PDCs in human blood1–5, bone marrow6, and cord blood11. Exclusive expression of CD304 (BDCA-4/Neuropilin-1) on PDCs allows their direct isolation. In blood and bone marrow, CD304 (BDCA-4/Neuropilin-1)+ PDCs are CD4+, CD45RA+, CD303 (BDCA-2)+, CD141 (BDCA-3)dim, CD1c (BDCA-1)–, and CD2–. They lack expression of lineage markers (CD3, CD14, CD16, CD19, CD20, CD56) and neither express myeloid markers such as CD13 and CD33, nor Fc receptors such as CD32, CD64, or FcεRI. Their lymphoid origin is indicated by their plasmacytoid morphology and the expression of the pre-T cell receptor α-chain. Freshly isolated CD1c (BDCA-1)+ or CD141 (BDCA-3)++ myeloid blood dendritic cells and monocytes do not express CD304 (BDCA-4/Neuropilin-1), but expression of CD304 (BDCA-4/Neuropilin-1) is induced on myeloid blood dendritic cells and monocytes upon culturing.1, 6 In inflamed tonsils, CD304 (BDCA-4/Neuropilin-1) expression is, apart from PDCs, also detected on some other cells, primarily follicular B helper memory T cells.6
CD304 (BDCA-4) was shown to be identical to neuropilin-1 (NP-1).6 Neuropilin-1 has formerly been discovered to be expressed on numerous nonhematopoietic cell types including neurons, endothelial and tumor cells.
Unlike binding of antibodies to CD303 (BDCA-2), binding of antibodies to CD304 (BDCA-4/Neuropilin-1) does not have a substantial effect on IFN type I production in PDCs after induction by, e.g., influenza virus.5, 6, 14
Downstream applications
Isolated CD304 (BDCA-4/Neuropilin-1)+ PDCs were used, for example, to examine expression of Toll-like receptors4, 7, 8, 12, chemokine receptors3, 8, 10, or antigens, e.g., EMR2,9 and for studies on dendritic cell activation4, migration3, cytokine production4, 6, 8, and T cell polarization4, 6, 13. Functional and phenotypical analysis was performed, e.g., of PDCs isolated from PMBCs and synovial fluid from psoriatic arthritis and rheumotoid arthritis patients15.
Columns
MS, LS, or autoMACS® Columns.
Overview
The CD304 (BDCA-4/Neuropilin-1) MicroBead Kit has been developed for the enrichment of plasmacytoid dendritic cells (PDCs) from PBMCs by positive selection.
