Technetium Tc-99m tilmanocept receptor (CD206, mannose receptor) (CD206)

Technetium-based radiopharmaceuticals such as technetium Tc‑99m tilmanocept are used for mapping the lymphatic system and guiding sentinel lymph node biopsy. These agents consist of a dextran backbone with multiple units of diethylenetriaminepentaacetic acid (DTPA) chelating technetium‑99m and multiple mannose residues that specifically bind to CD206 receptors on macrophages/dendritic cells within regional lymph nodes. After peritumoral injection, these molecules rapidly clear from the injection site via afferent lymphatics and accumulate at draining ("sentinel") nodes. Gamma cameras detect emitted radiation from bound technetium, allowing precise intraoperative localization of relevant nodes for biopsy or surgical planning. This technique improves staging accuracy in cancers with potential nodal spread while minimizing unnecessary extensive dissections. The key molecular target enabling this process is the CD206/mannose receptor expressed by reticuloendothelial cells within nodal tissue.

Other names

Mannose receptorMacrophage mannose receptorC-type lectin domain family 13 member D (MRC1)CD206

Radiolabeled agents such as technetium Tc‑99m tilmanocept bind selectively to mannose receptors (CD206) on macrophages and dendritic cells within lymph nodes. This allows localization of these nodes by gamma camera imaging due to emission of gamma rays from technetium decay.