Active Histidine Rich Glycoprotein (HRG)

HRG (Histidine-rich glycoprotein) is a plasma glycoprotein which is distinguished by its high content of histidine and proline. HRG binds a number of ligands such as heme, heparin, heparan sulfate, thrombospondin, plasminogen, and divalent 
metal ions. Thus, a functional binding ELISA assay was constructed to detect the association of rhHRG with heparin. Briefly, Microtiter wells were coated with OVA-conjugated-heparin. rhHRG were diluted serially in 0.01M PBS (pH 7.4). Duplicate samples of 100uL were then transferred to the coated microtiter wells and incubated for 2h at 37°C. Wells were washed with PBST and incubated for 1h with anti-HRG PAb, then aspirated and washed 3 times. After incubation with HRP labeled secondary antibody, wells were aspirated and washed 3 times. With the addition of substrate Solution, wells were incubated 15-25 minutes at 37°C. Finally, add 50µL stop solution to the wells and read at 450nm immediately.
The binding activity of rhHRG with heparin was shown in Figure 1 and this effect was in a dose dependent manner.