title: Anti-coagulation effect of Fc fragment against anti-β2-GP1 antibodies in mouse models with APS.
abstract: Anti-beta (2)-glycoprotein I (anti-β2-GP1) is one of the important pathogenesis factors responsible for thrombosis formation in patients with antiphospholipid syndrome (APS). Administration of intravenous immunoglobulin (IVIg) is a common method used to inhibit the abnormal antibody levels and decrease the mortality of APS in emergency situations. We hypothesize that the Fc fragment of IgG is the molecular structure responsible for these effects. The present study investigates the beneficial effects of both recombinant and natural human Fc fragments of heterogeneous IgG against human anti-β2-GP1 antibodies in mouse models with APS. Results showed that both recombinant and natural human Fc fragments moderately but significantly decreased the levels of serum anti-β2-GP1 antibodies and had anti-coagulation effects in human β2-GP1-immunized mice. Furthermore, both recombinant and natural human Fc fragments inhibited thrombosis formation and decreased mortality in mouse models infused intravenously with human anti-β2GP1 antibodies from patients with APS. Findings suggest that the Fc fragment might be one of the active structural units of heterogeneous IgG. Thus, recombinant human Fc fragment administration may be a useful treatment for individuals with APS.
authors.affiliation: Medical Research Center, Southwestern Hospital, The Third Military Medical University, Chongqing 400038, PR China.
authors.forename: Weidong
authors.initials: W
authors.lastname: Xie
authors.forename: Yaou
authors.initials: Y
authors.lastname: Zhang
authors.forename: Cunya
authors.initials: C
authors.lastname: Bu
authors.forename: Shijing
authors.initials: S
authors.lastname: Sun
authors.forename: Shaoliang
authors.initials: S
authors.lastname: Hu
authors.forename: Guoping
authors.initials: G
authors.lastname: Cai
mesh_terms: D000818:Animals; D017152:Antibodies, Antiphospholipid / Q000097:blood*; D000925:Anticoagulants / Q000008:administration & dosage / Q000276:immunology / Q000627:therapeutic use*; D016736:Antiphospholipid Syndrome / Q000097:blood / Q000188:drug therapy* / Q000276:immunology; D004195:Disease Models, Animal; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007116:Immunization, Passive; D007141:Immunoglobulin Fc Fragments / Q000008:administration & dosage / Q000276:immunology / Q000627:therapeutic use*; D016756:Immunoglobulins, Intravenous / Q000008:administration & dosage / Q000276:immunology / Q000627:therapeutic use; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000276:immunology / Q000627:therapeutic use; D053482:beta 2-Glycoprotein I / Q000276:immunology*
chemical_list: D017152:Antibodies, Antiphospholipid; D000925:Anticoagulants; D007141:Immunoglobulin Fc Fragments; D016756:Immunoglobulins, Intravenous; D011994:Recombinant Proteins; D053482:beta 2-Glycoprotein I