Serum protein microarray analysis of patients with preeclampsia

The present study identified novel factors related to preeclampsia. Serum samples were analyzed using a membrane-based human cytokine microarray technology in patients with preeclampsia. Serum was collected from 29 healthy pregnant subjects, 16 gestational hypertensive patients and 31 patients with preeclampsia. The samples for microarray analysis were randomly selected from 8 subjects, 5 patients with preeclampsia and 3 healthy pregnant controls. Serum was analyzed using a custom human cytokine microarray (RayBio® Custom Human Cytokine Array) designed to analyze 120 specific cytokines simultaneously. The levels of sTNF-R1, Axl and TIMP-2 were further measured by sandwich enzyme-linked immunosorbent assay (ELISA). In microarray analysis, there were no significant differences in most of the measured parameters among the two study groups, except in serum TNF-R1, Axl and TIMP-2 (P=0.021, P=0.034 and P=0.040, respectively). ELISA showed that the serum TNF-R1 levels were significantly higher in preeclampsia patients (288.06±78.30 pg/ml) compared to patients with gestational hypertension (229.81±47.65, P=0.005) and healthy pregnant subjects (247.48±59.00, P=0.009). Serum Axl levels were markedly higher in patients with preeclampsia (2.28±0.25 ng/ml) compared to patients with gestational hypertension (2.05±0.21 ng/ml) and healthy pregnant subjects (2.11±0.28, P=0.005). Additionally, preeclamptic patients had higher TIMP-2 levels (3.33±1.01  ng/ml) as compared to gestational hypertensive patients (3.13±0.56 ng/ml) and healthy pregnant women (3.00±0.49 ng/ml), but there was no pronounced difference between the three groups (F=1.285, P=0.283>0.05). Our results demonstrated that two biological processes related to inflammatory response and endothelium activation are involved in the pathogenesis of preeclampsia.