[Low prevalence of anti-annexin V antibodies in antiphospholipid syndrome with fetal loss].
OBJECTIVE
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%.


CONCLUSIONS
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.
Siaka
C
C
Laboratoire d'hémostase, hôpital Claude-Huriez, Lille, France.
Lambert
M
M
Caron
C
C
Amiral
J
J
Hachulla
E
E
Hatron
P Y
PY
Goudemand
J
J
D000022:Abortion, Spontaneous / Q000209:etiology*; D000293:Adolescent; D000328:Adult; D017304:Annexin A5 / Q000276:immunology*; D017152:Antibodies, Antiphospholipid / Q000032:analysis; D016736:Antiphospholipid Syndrome / Q000276:immunology; D001323:Autoantibodies / Q000032:analysis*; D003627:Data Interpretation, Statistical; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D008875:Middle Aged; D011247:Pregnancy; D011248:Pregnancy Complications / Q000276:immunology; D015995:Prevalence; D012680:Sensitivity and Specificity
D017304:Annexin A5; D017152:Antibodies, Antiphospholipid; D001323:Autoantibodies; D007074:Immunoglobulin G; D007075:Immunoglobulin M