The antigen recognized by ER-TR9 has recently been shown to be the murine analogue of the human DC SIGN (Dendritic Cell - Specific ICAM3 Grabbing Non Integrin), named SIGN R1. Antigen Distribution: Isolated Cells: The antigen is found on a subpopulation of phagocytic macrophages isolated from the spleen and showing acid phosphatase and moderate non-specific esterase activity. These phagocytes selectively ingest neutral polysaccharides such as Ficoll. Tissue Sections: Subpopulation of resident macrophages in the splenic marginal zone which are in the proximity of a certain B cell subpopulation (µ+, d-). It is also found on a subpopulation of macrophages localized in the medullary sinuses and trabecular sinuses of lymph nodes. Furthermore, macrophage subpopulations in other organs, such as some connective tissue macrophages in the dermis, may also show ER-TR9 antigen expression.

Monoclonal antibody ER-TR9 is a very useful marker for the identification of macrophage subpopulations present in the marginal zone of spleen and lymph node medulla. ER-TR9 is also useful when studying phagocytosis of polysaccharides since the antibody selectively inhibits uptake of these glycans by macrophages.

 This product was previously labelled as SIGN Related 1