This gene encodes a member of the immunoglobulin superfamily. The encoded protein is a lectin-like adhesion molecule that binds glycoconjugate ligands on cell surfaces in a sialic acid-dependent manner. It is a type I transmembrane protein expressed only by a subpopulation of macrophages and is involved in mediating cell-cell interactions. Alternative splicing produces a transcript variant encoding an isoform that is soluble rather than membrane-bound; however, the full-length nature of this variant has not been determined.