摘要
Objective To investigate cloning and expression of β 2 glycoprotein 1 (β 2GP1) recognized by antiphospholipid antibodies and to study the clinical significance of anti β 2GP1 antibodies in patients with autoimmune disease. Methods By using reverse transcription PCR method, two kinds of expression plasmid which expressed β 2GP1 and the fifth domain of β 2 glycoprotein 1 (β 2GP1 D5) proteins respectively were constructed in this study. Their antigenic activities were identified by immunoblots using rabbit anti β 2GP1 antibodies. Anti rβ 2GP1 and anti rβ 2GP1 D5 antibodies in the 112 patents were detected by ELISA using rβ 2GP1 and rβ 2GP1 D5 as coating antigens. Results A significant correlation in statistics (r= 0.667, P<0.01) between the levels of anti rβ 2GP1 and anticardiolipin antibodies (aCL) was found. The presence of anti rβ 2GP1 antibodies was associated with an increased frequency of history of thrombosis and/or recurrent abortion. Anti rβ 2GP1 assay provided better specificity than conventional aCL assay. The binding of anti rβ 2GP1 from the sera of patients with antiphospholipid syndrome (APS) to rβ 2GP1 was inhibited by rβ 2GP1 D5. Meanwhile, of 28 patients who had positive anti rβ 2GP1 antibodies in sera, 27 (96.4%) had positive anti rβ 2GP1 D5 antibodies. Conclusion It is indicated that antigenic epitope of β 2GP1 might be located in its fifth domain. Detection of anti rβ 2GP1 antibodies may be of potential value for evaluating the risk of thrombosis and/or other APS associated symptom.
Objective To investigate cloning and expression of β 2 glycoprotein 1 (β 2GP1) recognized by antiphospholipid antibodies and to study the clinical significance of anti β 2GP1 antibodies in patients with autoimmune disease. Methods By using reverse transcription PCR method, two kinds of expression plasmid which expressed β 2GP1 and the fifth domain of β 2 glycoprotein 1 (β 2GP1 D5) proteins respectively were constructed in this study. Their antigenic activities were identified by immunoblots using rabbit anti β 2GP1 antibodies. Anti rβ 2GP1 and anti rβ 2GP1 D5 antibodies in the 112 patents were detected by ELISA using rβ 2GP1 and rβ 2GP1 D5 as coating antigens. Results A significant correlation in statistics (r= 0.667, P<0.01) between the levels of anti rβ 2GP1 and anticardiolipin antibodies (aCL) was found. The presence of anti rβ 2GP1 antibodies was associated with an increased frequency of history of thrombosis and/or recurrent abortion. Anti rβ 2GP1 assay provided better specificity than conventional aCL assay. The binding of anti rβ 2GP1 from the sera of patients with antiphospholipid syndrome (APS) to rβ 2GP1 was inhibited by rβ 2GP1 D5. Meanwhile, of 28 patients who had positive anti rβ 2GP1 antibodies in sera, 27 (96.4%) had positive anti rβ 2GP1 D5 antibodies. Conclusion It is indicated that antigenic epitope of β 2GP1 might be located in its fifth domain. Detection of anti rβ 2GP1 antibodies may be of potential value for evaluating the risk of thrombosis and/or other APS associated symptom.
