Complex sentence: DC-SIGN or CD209 is a C-type lectin receptor present mainly on myeloid and pre-plasmacytoid dendritic cells that mediates dendritic cell rolling interactions with blood endothelium and activation of CD4 + T cells, as well as recognition of pathogen haptens.
Split into simpler sentences: DC-SIGN or CD209 is a C-type lectin receptor present on both macrophages and Dendritic cells. On myeloid and pre-plasmacytoid dendritic cells DC-SIGN mediates dendritic cell rolling interactions with blood endothelium and activation of CD4 + T cells, as well as recognition of pathogen haptens.