Abstract: Tumor necrosis factor α(TNFα) is recognized as the principal inflammatory mediator in the pathogenesis of endotoxemia and dyscracia. Removal of TNFα with immunoadsorbent is one of the focus in the study of anti-TNFα therapy. In the present study, γ-globulin IgG was immobilized onto agarose beads to produce a new type TNFα adsorbent. The affinity mechanism of IgG ligand was studied by means of IgG molecule modification with chemical reagents. The results showed that amino group had a significant influence on the adsorption capacity; carboxyl and indole groups had a negative effect; guanidine and imidazole groups had no effect on adsorption capacity. Furthermore, 1,6-hexamethylene diamine(DAH) was used as a spacer to link agar gel support and IgG ligand which was favourable for reducing the steric hindrance and elevating the adsorption capacity. The IgG immobilized adsorbent showed a strong specificity as well as high efficacy and therefore had a potential for clinical application.

Key words: TNFα, IgG, Modification, Mechanism