Selective expression of human fascin (p55) by dendritic leukocytes.

Abstract

Dendritic cells are a heterogeneous group of antigen presenting leukocytes with distinctive cell morphology and function. The highly developed capacity of dendritic cells to present antigens and the way in which cells of variable maturity differ in their ability to take up, process, and present antigens have been well characterized (1–6). Dendritic cells are derived from cells in bone marrow in vivo and are released to peripheral blood and tissues (7,8), but dendritic cells can be generated in vitro from CD34 positive precursor cells (9–13). The position of dendritic cells in the hierarchy of hematopoietic cells remains to be established but the study of human blood dendritic and progenitor dendritic cells has been restricted by the lack of selective markers for this specialized subset of antigen presenting cells. Recently, an evolutionary conserved human actin-binding protein, fascin (p55), was demonstrated to be highly expressed by circulating blood dendritic cells (14). In the course of studying the development, migration and tissues distribution of dendritic cells we took advantage of a novel monoclonal antibody against p55 to examine the differential expression of p55 in immature, circulating, and tissue dendritic cells.