Purity ~95% (SDSPAGE). The MMR (macrophage mannose receptor) is also called MR due to its presence on cells other than macrophages, and is designated CD206, Mrc1 (mannose receptor C type 1), or CLEC13D (Ctype lectin domain family 13, member D) (1-4). CD206 is a 175kD endocytic receptor that is expressed on M2 alternatively activated tissue macrophages including tumor-associated macrophages (TAMs), inflammatory dendritic cells in selected lymphoid organs, and liver, splenic, lymphatic, and dermal microvascular endothelial cells (1, 2, 58). The 1463 amino acid (aa) rat CD206 precursor contains a signal sequence (26aa), an extracellular domain (ECD) containing an Nterminal cysteinerich domain, a fibronectin type II (FNII) domain, eight Ctype lectin domains (CTLDs), and several Nglycosylation sites (1369aa), a transmembrane segment and a short (47aa) cytoplasmic domain (24). Metalloproteinases can mediate the shedding of the soluble ECD (2). The rat CD206 ECD shares 96% aa sequenc