Re-examining the proposed lectin properties of IL-2

Early work examining the interactions of IL-2 and the urinary glycoprotein uromodulin led to the suggestion that IL-2 was a lectin with specificity for high-mannose and mannan ligands. Subsequent studies have attributed various roles to these properties, some critical to the cell proliferative activity of IL-2. In an attempt to verify the reported interaction between IL-2 and mannose containing carbohydrate ligands we studied two biologically active forms of IL-2 using various techniques including affinity chromatography, equilibrium dialysis, and NMR methods. Despite previous reports we have not been able to demonstrate that IL-2 possesses the ability to bind carbohydrate.