Heparan sulfate (HS) is a linear
polysaccharide found in all animal tissues. It occurs as a
proteoglycan (HSPG) in which two or three HS chains are attached in close proximity to cell surface or extracellular matrix proteins. It is in this form that HS binds to a variety of protein
ligands and regulates a wide variety of biological activities, including developmental processes,
angiogenesis,
blood coagulation, abolishing detachment activity by GrB (Granzyme B), and tumour
metastasis. HS has been shown to serve as cellular receptor for a number of viruses including the
respiratory syncytial virus (Hallak et al. 2000)