These ligands circulate throughout the body owing to weak affinity for HSGAG (heparan sulphate glycosaminoglycan), and they require α-klotho–β-klotho proteins as cofactors for their activity.
Based on neurite outgrowth assays, we have previously isolated, cloned, and produced as recombinant proteins two ligands of heparan sulfate proteoglycans (HSPGs), HMGB1 (high-mobility group B1; ...