Lectin compositions and methods for modulating an immune response to an antigen

A composition comprising a nucleic acid molecule encoding a fusion polypeptide, said fusion polypeptide comprising

• a first amino acid sequence which is selected from:
• a carbohydrate binding domain of a collectin;
• a carbohydrate binding domain of a galectin;
• a carbohydrate binding domain of a C-type lectin;
• or an amino acid sequence which can bind to a carbohydrate on a glycoprotein, said carbohydrate being chosen from the group:
• D-mannose, D-glucose, D-fucose, L-fucose, N-acetyl-beta-D-glucosamine, N-acetyl-beta-D-glucosamine, a sialic acid;
• and
• a second amino acid sequence comprising a ligand for a cell surface polypeptide, said ligand being chosen from the group:
• a ligand for a cytokine receptor, a ligand for CD40, a ligand for an adhesion molecule, a ligand for a defensin receptor, a ligand for a heat shock protein receptor, a ligand for a counterreceptor for a T cell costimulatory molecule.