Affiliation: | a Genzyme Corp., 153 Second Avenue, Waltham, MA 02451, USA b AnorMED, Inc., 200-20353 64th Avenue, Langley, British Columbia, Canada V2Y 1N5 c Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium |