Sialoadhesin, a macrophage sialic acid binding receptor for haemopoietic cells with 17 immunoglobulin-like domains

EMBO J. 1994 Oct 3;13(19):4490-503.


Sialoadhesin is a macrophage-restricted adhesion molecule of 185 kDa that mediates sialic acid-dependent binding to cells. It is expressed strongly by macrophages in lymphoid and haemopoietic tissues where it is likely to mediate cell-cell interactions. Here we report the molecular cloning of murine sialoadhesin and show that it is a new member of the immunoglobulin (Ig) superfamily with 17 Ig-like domains. COS cells transfected with a cDNA encoding full-length sialoadhesin bound mouse bone marrow cells in a sialic acid-dependent manner. Alternatively spliced cDNAs, predicting soluble forms of sialoadhesin containing the first three or 16 Ig-like domains of sialoadhesin, were expressed in COS cells and the respective proteins purified. When immobilized on plastic, the 16-domain form bound cells in a sialic acid-dependent manner, suggesting that sialoadhesin can function in both secreted and membrane-bound forms. The most similar proteins in the database were CD22, myelin-associated glycoprotein, Schwann cell myelin protein and CD33. Like sialoadhesin, CD22 mediates sialic acid-dependent cell adhesion. The sequence similarity of sialoadhesin to CD22 and related members of the Ig superfamily indicates the existence of a novel family of sialic acid binding proteins involved in cell-cell interactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Bone Marrow Cells
  • Carbohydrate Sequence
  • Cell Adhesion Molecules / chemistry*
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / physiology*
  • Cell Line
  • Cloning, Molecular
  • Erythrocytes / physiology
  • Humans
  • Immunoglobulins / chemistry
  • Macrophages / physiology*
  • Membrane Glycoproteins / chemistry*
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / physiology*
  • Mice
  • Mice, Inbred BALB C
  • Molecular Sequence Data
  • Receptors, Immunologic / chemistry*
  • Receptors, Immunologic / genetics
  • Receptors, Immunologic / physiology*
  • Sequence Homology, Amino Acid
  • Sialic Acid Binding Ig-like Lectin 1


  • Cell Adhesion Molecules
  • Immunoglobulins
  • Membrane Glycoproteins
  • Receptors, Immunologic
  • SIGLEC1 protein, human
  • Sialic Acid Binding Ig-like Lectin 1
  • Siglec1 protein, mouse

Associated data

  • GENBANK/Z36233
  • GENBANK/Z36234
  • GENBANK/Z36293