Detection of anti-recombinant beta 2-glycoprotein 1 and anti-recombinant beta 2-glycoprotein 1 fifth-domain antibodies in sera from patients with systemic lupus erythematosus.
Two kinds of plasmid expression vectors which expressed beta 2-glycoprotein 1 (beta 2GP1) and the fifth domain of beta 2-glycoprotein 1 (beta 2GP1-D5) were constructed respectively in this study. The antigenicity of recombinant beta 2GP1 (r beta 2GP1) and beta 2GP1-D5 (r beta 2GP1-D5) was identified by immunoblots using rabbit anti-beta 2GP1 antibodies, and the recombinant proteins were purified. Both anti-r beta 2GP1 and anti-beta 2GP1-D5 antibodies in 112 patients were detected by ELISA using r beta 2GP1 and r beta 2GP1-D5 as coating antigens. A significant statistical correlation (r = 0.667, P < 0.01) between the levels of anti-beta 2GP1 and anticardiolipin (ACL) antibodies was found. The presence of anti-r beta 2GP1 antibodies was associated with an increased frequency of history of thrombosis and/or recurrent abortion; hence anti-r beta 2GP1 assay provided better specificity than conventional ACL assay. Detection of anti-r beta 2GP1 antibodies may be of potential value in evaluating the risk of thrombosis and/or symptoms associated with other antiphospholipid syndromes (APS). The binding of anti-r beta 2GP1 from the sera of patients with APS to r beta 2GP1 was inhibited by r beta 2GP1-D5. Meanwhile, of 28 patients who had positive anti-r beta 2GP1 antibodies in sera, 27 (96.4%) had positive anti-r beta 2GP1-D1 antibodies. This indicated that the antigenic epitope of beta 2GP1 may be located in its fifth domain.
Department of Clinical Immunology, Jin-ling Hospital, School of Medicine, Nanjing University, China.
C D
CD
Yang
S L
SL
Chen
N
N
Shen
M
M
Qi
F
F
Xu
D000026:Abortion, Habitual / Q000276:immunology; D017153:Antibodies, Anticardiolipin / Q000032:analysis; D001053:Apolipoproteins / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis*; D003001:Cloning, Molecular; D017931:DNA Primers / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology*; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D012313:RNA / Q000032:analysis; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D012008:Recurrence; D013927:Thrombosis / Q000276:immunology; D053482:beta 2-Glycoprotein I
D017153:Antibodies, Anticardiolipin; D001053:Apolipoproteins; D001323:Autoantibodies; D017931:DNA Primers; D006023:Glycoproteins; D007074:Immunoglobulin G; D011993:Recombinant Fusion Proteins; D053482:beta 2-Glycoprotein I; D012313:RNA