1. Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom, Micromass UK Ltd., Floats Road, Wythenshawe, Manchester, M23 9LZ, United Kingdom, and Laboratory of Molecular Immunology, Rega Institute, University of Leuven, Minderbroederstraat 10, 3000 Leuven, Belgium