Figure 5.
Competition SPR corroborates ApoE’s recognition of 3-O-S in LMWHS Array. (A) Scheme for competition SPR. (B) SPR competition with chemically desulfated heparin. The inhibition of ApoE/Heparin interactions by chemically desulfated heparin indicates that the 6-O-S group plays a large role compared to the 2-O-S group. Whereas fully sulfated heparin almost completely abolishes ApoE3 binding to the heparin chip, 2-O-desulfated heparin retains about 60% ApoE binding, while 6-O-S desulfated heparin retains 80% binding and N-desulfated heparin retains 70%. (C) The 3-O-Sulfated Oligo-19 inhibits ApoE3-HS binding with an IC50 of 0.4 μM, compared to (D) oligo-20, which inhibits ApoE-HS binding with an IC50 of 2.2 μM. Error bars are ± SEM.