β-Galactosidase treatment is a common first-stage modification of the three major subtypes of Gc protein to GcMAF

Anticancer Res. 2012 Jun;32(6):2359-64.

Abstract

Background: The 1f1f subtype of the group-specific component (Gc) protein is converted into Gc protein-derived macrophage-activating factor (GcMAF) by enzymatic processing with β-galactosidase and sialidase. We previously demonstrated that preGc(1f1f)MAF, a full Gc(1f1f) protein otherwise lacking a galactosyl moiety, can be converted to GcMAF by treatment with mouse peritoneal fluid. Here, we investigated the effects of the β-galactosidase-treated 1s1s and 22 subtypes of Gc protein (preGc(1s1s)MAF and preGc₂₂MAF) on the phagocytic activation of mouse peritoneal macrophages.

Results: We demonstrated the presence of Gal-GalNAc disaccharide sugar structures in the Gc(1s1s) protein by western blotting using peanut agglutinin and Helix pomatia agglutinin lectin. We also found that preGc(1s1s)MAF and preGc₂₂MAF significantly enhanced the phagocytic activity of mouse peritoneal macrophages in the presence and absence of mouse peritoneal fluid.

Conclusion: We demonstrate that preGc(1s1s)MAF and preGc₂₂MAF proteins can be used as effective macrophage activators.

MeSH terms

  • Animals
  • Blotting, Western
  • Humans
  • Macrophage Activation / physiology*
  • Macrophage-Activating Factors / metabolism*
  • Macrophages / metabolism
  • Mice
  • Phagocytosis / physiology
  • Vitamin D-Binding Protein / metabolism*
  • beta-Galactosidase / metabolism*

Substances

  • Macrophage-Activating Factors
  • Vitamin D-Binding Protein
  • beta-Galactosidase