TY - JOUR T1 - Effect of the Gc-derived Macrophage-activating Factor Precursor (preGcMAF) on Phagocytic Activation of Mouse Peritoneal Macrophages JF - Anticancer Research JO - Anticancer Res SP - 2489 LP - 2492 VL - 31 IS - 7 AU - YOSHIHIRO UTO AU - SYOTA YAMAMOTO AU - RYOTA TAKEUCHI AU - YOSHINORI NAKAGAWA AU - KEIJI HIROTA AU - HIROSHI TERADA AU - SHINYA ONIZUKA AU - EIJI NAKATA AU - HITOSHI HORI Y1 - 2011/07/01 UR - http://ar.iiarjournals.org/content/31/7/2489.abstract N2 - Background: The 1f1f subtype of the Gc protein (Gc1f1f protein) was converted into Gc-derived macrophage-activating factor (GcMAF) by enzymatic processing in the presence of β-galactosidase of an activated B-cell and sialidase of a T-cell. We hypothesized that preGc1f1fMAF, the only Gc1f1f protein lacking galactose, can be converted to GcMAF in vivo because sialic acid is cleaved by residual sialidase. Hence, we investigated the effect of preGc1f1fMAF on the phagocytic activation of mouse peritoneal macrophages. Results: We examined the sugar moiety of preGc1f1fMAF with a Western blot using peanut agglutinin (PNA) and Helix pomatia agglutinin (HPA) lectin. We also found that preGc1f1fMAF significantly enhanced phagocytic activity in mouse peritoneal macrophages but only in the presence of the mouse peritoneal fluid; the level of phagocytic activity was the same as that observed for GcMAF. Conclusion: PreGc1f1fMAF can be used as an effective macrophage activator in vivo. ER -