RT Journal Article SR Electronic T1 β-Galactosidase Treatment Is a Common First-stage Modification of the Three Major Subtypes of Gc Protein to GcMAF JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 2359 OP 2364 VO 32 IS 6 A1 YOSHIHIRO UTO A1 SYOTA YAMAMOTO A1 HIROTAKA MUKAI A1 NORIKO ISHIYAMA A1 RYOTA TAKEUCHI A1 YOSHINORI NAKAGAWA A1 KEIJI HIROTA A1 HIROSHI TERADA A1 SHINYA ONIZUKA A1 HITOSHI HORI YR 2012 UL http://ar.iiarjournals.org/content/32/6/2359.abstract AB 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 preGc1f1fMAF, a full Gc1f1f 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 (preGc1s1sMAF and preGc22MAF) on the phagocytic activation of mouse peritoneal macrophages. Results: We demonstrated the presence of Gal-GalNAc disaccharide sugar structures in the Gc1s1s protein by western blotting using peanut agglutinin and Helix pomatia agglutinin lectin. We also found that preGc1s1sMAF and preGc22MAF significantly enhanced the phagocytic activity of mouse peritoneal macrophages in the presence and absence of mouse peritoneal fluid. Conclusion: We demonstrate that preGc1s1sMAF and preGc22MAF proteins can be used as effective macrophage activators.