PURPOSE: Annexin V, a protein with potent anticoagulant activity has a calcium-dependent binding affinity for phospholipids. Annexin V is distributed in many organs, especially in the placenta and endothelium. Various studies have shown that placental annexin V is decreased in women with anti-phospholipid syndrome. It has been suggested that annexin V might be a target of anti-phospholipid antibodies and that the subsequent decrease in annexin V might be associated with obstetrical complications. We investigated the presence of anti-annexin V antibodies in the plasma of women with anti-phospholipid syndrome and obstetrical complications. METHODS: Twenty-three patients with at least one spontaneous abortion were included in the study. Anti-cardiolipin antibodies and lupus anticoagulant were present in 87% and 30% of the patients, respectively. A group of 40 healthy women were included in the control group. Anti-annexin V IgG and IgM antibodies were measured by ELISA. RESULTS: The IgG mean OD was 0.07 +/- 0.013 in patients and 0.042 +/- 0.06 in the control group. There was no significant difference between the two groups (P = NS). Only two out of the 23 patients and two out of the 40 healthy women were positive for IgG (OD > 0.25). The sensitivity of the assay was poor (8.7%). Even when the threshold was adjusted according to the mean OD in control subjects +2 SD, the sensitivity was still poor, reaching only 13%. CONCLUSION: The prevalence of anti-annexin V was low in patients with anti-phospholipid syndrome and repetitive spontaneous abortions. Anti-annexin V assay does not appear to be sensitive enough for the identification of anti-phospholipid antibodies that might be involved in the decrease in annexin V leading subsequently to thrombosis risk.
PURPOSE:Annexin V, a protein with potent anticoagulant activity has a calcium-dependent binding affinity for phospholipids. Annexin V is distributed in many organs, especially in the placenta and endothelium. Various studies have shown that placental annexin V is decreased in women with anti-phospholipid syndrome. It has been suggested that annexin V might be a target of anti-phospholipid antibodies and that the subsequent decrease in annexin V might be associated with obstetrical complications. We investigated the presence of anti-annexin V antibodies in the plasma of women with anti-phospholipid syndrome and obstetrical complications. METHODS: Twenty-three patients with at least one spontaneous abortion were included in the study. Anti-cardiolipin antibodies and lupus anticoagulant were present in 87% and 30% of the patients, respectively. A group of 40 healthy women were included in the control group. Anti-annexin V IgG and IgM antibodies were measured by ELISA. RESULTS: The IgG mean OD was 0.07 +/- 0.013 in patients and 0.042 +/- 0.06 in the control group. There was no significant difference between the two groups (P = NS). Only two out of the 23 patients and two out of the 40 healthy women were positive for IgG (OD > 0.25). The sensitivity of the assay was poor (8.7%). Even when the threshold was adjusted according to the mean OD in control subjects +2 SD, the sensitivity was still poor, reaching only 13%. CONCLUSION: The prevalence of anti-annexin V was low in patients with anti-phospholipid syndrome and repetitive spontaneous abortions. Anti-annexin V assay does not appear to be sensitive enough for the identification of anti-phospholipid antibodies that might be involved in the decrease in annexin V leading subsequently to thrombosis risk.
Authors: B de Laat; R H W M Derksen; I J Mackie; M Roest; S Schoormans; B J Woodhams; P G de Groot; W L van Heerde Journal: Ann Rheum Dis Date: 2006-01-31 Impact factor: 19.103
Authors: Marta P Baleva; Zhivka P Karagyozova; Milena K Nikolova-Vlahova; Krasimir V Nikolov; Petar K Nikolov Journal: Cent Eur J Immunol Date: 2014-10-14 Impact factor: 2.085