Effect of IgG dimer concentration on the binding ability of IgG Fc fragment in IVIG to THP-1 cell surface receptors

Abstract

Objective To investigate the effect of immunoglobulin G (IgG) dimer concentration of intravenous immunoglobulin (IVIG) on the binding ability of IgG Fc fragment to THP-1 cell surface receptors. Methods Firstly, protein purification and high performance liquid chromatography (HPLC) were used to prepare different concentrations of IgG dimers. After that, IgG dimer was added to IVIG to prepare IVIG containing different concentrations of IgG dimer. Finally, based on the method established in our laboratory, we analyzed the effect of IgG dimer concentration in IVIG on the binding ability of IgG Fc fragment to THP-1 cell surface receptors. Results When the concentration of IgG dimer in IVIG was 1.11%-10.30%, its binding ability to Fc receptors on the surface of THP-1 cell was 97.67%-135.33%, and this binding ability was positively correlated with the concentration of IgG dimer. When the IgG dimer concentration exceeded 13.22%, the binding ability had no correlation with the IgG dimer concentration. Conclusion A certain concentration of IgG dimer can promote the binding ability of the IgG Fc fragment in IVIG to receptors on the surface of THP-1 cells, which needs further verification from animal experiments and clinical data.

Keywords

• ivig
• igg dimer
• igg fc fragment
• thp-1 cells
• receptor binding ability