Rabbit Anti-Human SIGLEC1 monoclonal antibody for IHC-P. CD169 or sialoadhesin is a cell adhesion molecule on the surface of some macrophages distributed in the spleen, liver, lymph node, bone marrow, colon, lung, and various inflammatory tissues. It acts as an endocytic receptor mediating clathrin-dependent endocytosis. CD169 predominately binds to neutrophils, but can also bind to monocytes, natural killer cells, B cells and a subset of cytotoxic T cells by interacting with sialic acid molecules on their surfaces of their ligands.