Type I IFN-profile in platelets. A schematic model describing interactions between immune complexes (ICs), interferonα (IFNα), and cells supported by the experiments reported here. RNA and DNA containing ICs induce IFNα production from plasmacytoid dendritic cells (pDCs) in the circulation (1). IFNα induces increased expression of type I IFN-regulated genes and proteins in the megakaryocytes in the bone marrow (2-3). The platelets are released from the megakaryocytes and enter the circulation (4).