Table 1.
Important protein markers for prediction of pre-eclampsia.
| Marker | Type of protein | Function | Gestational age | Combinations of markers for prediction |
|---|---|---|---|---|
| PAPP-A | Metalloproteases | Cleaves insulin growth factor from its binding proteins | 11–13 weeks | pp-13, uterine artery Doppler, PIGF, sEng, ADAM12 |
| ADAM12 | Metalloproteases | Modulates the activity of insulin growth factors | 11–14 weeks | PAPP-A, uterine artery Doppler, PIGF, MAP |
| Cystatin C | Cysteine protease inhibitor | Inhibits cysteine proteases cathepsins B and L and involved in trophoblast invasion | 15–20 weeks | β2-Macroglobulin |
| pp-13 | Galectin family of proteins | Placental implantation and maternal vascular remodeling | 9–12 weeks 11–13 weeks |
Individual predictor, PIGF, PAPP-A, uterine artery Doppler, P-selectin |
| Pentraxin-3 | Humoral immune system component | Prevents maternal alloimmunization against the fetus | 11–14 weeks | Individual predictor, uterine artery Doppler |
| P-selectin | Cell surface adhesion molecule | Role in inflammatory reactions and recruitment of leucocytes | 10–14 weeks | Individual predictor, activin A, inhibin A, PTX3, PIGF, pp-13 |
| ADMA | Inhibitor of NO synthase | Reversibly inhibits release of NO | 23–25 weeks | Individual predictor |
| hCG | Hormone | Maintains corpus luteum, promotes progesterone production, and differentiation of cytotrophoblast | Second trimester | Individual predictor, uterine artery Doppler |
| Inhibin A and activin A | Hormone | Development of placenta, trophoblast cell differentiation and regulation of gonadotrophins | Second trimester | PIGF, uterine artery Doppler, PP-13, P-selectin, PTX3, PIGF |
| CRH | Hormone | Stimulates ACTH release | Second trimester | CRH-binding protein |
| VEGF | Proangiogenic factor | Angiogenesis and maintaining placental vasculature | Second trimester | PIGF, sFlt-1, sEng |
| PIGF | Proangiogenic factor | Angiogenesis, maintaining placental vasculature | Second trimester | sFlt-1, VEGF, sEng, PAPP-A, pp -13, activin A, inhibin A, PTX3 |
| sFlt-1 | Antiangiogenic factor | Blood vessel homeostasis, trophoblast cell function | Second trimester | PIGF, VEGF, sEng |
| sEng | Antiangiogenic factor | Angiogenesis, regulates NO synthesis, vasodilation, capillary formation | Second trimester | PIGF, VEGF, sFlt-1, PAPP-A, pp -13 activin A, inhibin A, PTX3 |
ACTH, adrenocorticotropicohormone; ADAM12, A disintegrin and metalloprotease12; ADMA, asymmetric dimethyl arginine; CRH, corticotropin-releasing hormone; hCG, human chorionic gonadotropin; MAP, mean arterial pressure; NO, nitric oxide; pp-13, placental protein-13; PIGF, placental growth factor; PAPP-A, pregnancy-associated plasma protein A; sEng, soluble endoglin; sFlt-1, soluble fms-like tyrosine kinase 1; TGF β, transforming growth factor β; VEGF, vascular endothelial growth factor.