The function of elevated plasma fibronectin in preeclampsia.

Total plasma fibronectin is elevated in preeclampsia due to vascular injury release, increased production, or enzymatic degradation resulting in multimers. To examine the etiology of the fibronectin increase in preeclampsia, we quantified plasma fibronectin in nonpregnant women, pregnant women from 28 to 42 weeks' gestation, latent labor, and preeclampsia by both nephelometry and turbidimetry. Western blotting and gel electrophoresis were used to examine the structural integrity of the fibronectin molecule. In addition, functional assays explored the potential for dysfunctional fibronectin. Fibronectin was elevated in pregnant patients compared with nonpregnant patients and exhibited a further significant increase with preeclampsia. The increase was not a result of degradation to multimers but possibly to increased variants. Notably, fibronectin function, as defined by collagen binding, may be impaired during pregnancy and preeclampsia. It appears that the clinical pathophysiology of preeclampsia may be related to dysfunctional fibronectin measured by collagen binding.