1. Immunol Lett. 2009 Jun 4;124(2):77-80. Epub 2009 May 3.

Analysis of sialoadhesin expression on mouse alveolar macrophages.

Ducreux J, Crocker PR, Vanbever R.

Department of Pharmaceutical Technology, Université catholique de Louvain, 1200
Brussels, Belgium.

Sialoadhesin (Sn) is a macrophage-restricted receptor that was first
characterised on mouse resident bone marrow macrophages as a receptor that
mediates the binding, without ingestion, of sheep erythrocytes. Sn is highly
conserved in mammals but its expression on tissue macrophages is heterogeneous.
In the mouse, high levels of erythrocytes binding are shown on macrophages from
lymphoid tissues but a low erythrocytes binding activity is detectable on
macrophages isolated from the broncho-alveolar space. Yet, Sn expression has been
demonstrated on human, rat and pig alveolar macrophages (AM) using methods of
molecular biology. Therefore, the present study aimed to investigate the
expression of Sn on mouse AM in order to confirm the presence of the protein on
this population of murine macrophages. Using cytometrical analyses, we showed
that Sn was expressed on mouse AM surface. Following desialylation, AM largely
bound erythrocytes and this binding was inhibited by 3D6, an anti-mouse Sn
monoclonal antibody, in a dose-dependent manner. This indicates that Sn is
expressed on mouse AM but that the sialic acid binding activity mediated by this 
molecule is naturally masked by endogenous sialic acid within the glycocalyx on
the cell surface.

PMID: 19406152 [PubMed - indexed for MEDLINE]