Control of Mac-2 surface expression on murine macrophage cell lines

Eur J Immunol. 1994 Jan;24(1):216-21. doi: 10.1002/eji.1830240134.


Mac-2 antigen, a 32-kDa murine macrophage cell-surface protein expressed on thioglycollate-elicited peritoneal exudate cells at higher levels than other macrophages, is a member of the S-(soluble) galactoside-binding lectin family with homologies to carbohydrate-binding proteins of other cell types. Murine macrophage cell lines can be ordered in a linear differentiation sequence according to their expression of Mac-2 and other surface markers (Leenen et al., Differentiation 1986. 32: 157.) We show here that antigen expression in macrophage cell lines can be regulated at the level of protein secretion. WEHI-3 cells, classified as immature macrophages by virtue of their low level of surface Mac-2 expression synthesize similar amounts of the antigen as more mature J774.2 and P388.D1 cells that express high amounts of surface Mac-2, but unlike these latter cell lines WEHI-3 cells fail to secrete the protein. Exogenously added Mac-2 binds efficiently to WEHI-3 cells and putative Mac-2-binding carbohydrates are expressed equally on WEHI-3, J774.2 and P388.D1 cells as judged by binding of plant lectins of known carbohydrate-binding specificities. Mac-2 secretion and surface expression in WEHI-3 cells is not significantly enhanced by calcium ionophore A23187, a powerful stimulator of Mac-2 secretion in other cells and a moderate stimulator in J774.2 and P388.D1 cells. WEHI-3 cells provide a valuable system for studying the mechanism of intracellular transport and secretion of Mac-2, a protein that lacks a signal sequence and does not enter the classical secretory pathway.

MeSH terms

  • Animals
  • Antibodies, Monoclonal
  • Antigens, Differentiation / biosynthesis*
  • Antigens, Differentiation / isolation & purification
  • Blotting, Western
  • Cell Line
  • Electrophoresis, Polyacrylamide Gel
  • Flow Cytometry
  • Galectin 3
  • Lectins
  • Macrophages / cytology*
  • Macrophages / immunology*
  • Mice
  • Precipitin Tests


  • Antibodies, Monoclonal
  • Antigens, Differentiation
  • Galectin 3
  • Lectins