Effects of mannose and mannose derivatives on the clearance of IgG antibody-coated erythrocytes in the rat.

摘要: The effects of D-mannose, mannose dimers, mannan, or lactotransferrin [a glycoprotein containing alpha-(1,6) linkages] infusion on the clearance IgG-coated, 99mTc-labelled, autologous red blood cells (IgG-RBC) by spleen and liver were investigated in rat. Untreated rat RBC labelled with 111In simultaneously injected to correct for 99mTc present contained each organ. In normal rats, mean specific uptake (per g) IgG-RBC was about 10 times higher than g). Consistent curves IgG-RBC, splenic those significantly decreased after injections, compared that measured rats control receiving i.v. physiological saline, 5% 15% glucose. contrast, remained unchanged under otherwise identical experimental conditions. blockade induced mannan derivatives dose-dependent, C3-independent spontaneously reversible within 42 hr. Splenic macrophages isolated from mannose- mannan-treated animals expressed a receptor activity Fc domain IgG, whereas no consistent effect C3 receptors noted. These data show transient impairment Fc(IgG)-receptor function injection D-mannose derivatives. They support concept simple sugar compounds can exhibit immunoregulatory activities vivo, as has been already shown vitro.