Maturation and function of plasmacytoid dendritic cells

Dendritic cells (DCs) are comprised of a number of subsets with distinct functions. An example is plasmacytoid DCs (PDCs), also known as type I interferon-producing cells. Other studies have demonstrated some heterogeneity in PDCs. While it is known that proliferating progenitors exist in the bone marrow, little attention has been paid to intermediate stages of PDC development. Here we show PDCs express. We here show that Ly49Q, a lectin-type natural killer cell inhibitory receptor, is expressed on Gr-1+ cells including PDCs in spleen and bone marrow. It is found that different expression levels of Ly49Q define sequential developmental stages of PDCs in bone marrow. Functional roles of PDC subsets in T cell activation are also investigated in reference to human PDCs.