Immunohistochemical staining of IGF-I, IGF-binding proteins-1 and -3, and transforming growth factor beta-3 in the umbilical cords of preeclamptic patients

Abstract

Background. To detect the immunoreactivity of insulin-like growth factor-I, insulin-like growth factor-binding proteins-1 and -3 and transforming growth factor beta-3 in the umbilical cords of normal and preeclamptic patients. Methods. Umbilical cords were obtained from 15 normal and 15 preeclamptic patients. Immunoreactivities were determined using either indirect immunofluorescence or immunoperoxidase techniques on formalin-fixed, paraffin-embedded sections. Staining intensity was graded by a semiquantitative scoring method. The results were compared by Mann-Whitney U-test. Results. The umbilical cords were thinner and the vessels were hypoplastic in the preeclamptic group. Moderate staining intensity for insulin-like growth factor-I, insulin-like growth factor binding protein-1 and -3 and transforming growth factor-beta 3 was observed in normal patients. The preeclamptic group had mild and strong intensities for insulin-like growth factor-I and insulin-like growth factor binding protein-1, respectively, and intensity for insulin-like growth factor binding protein-3 did not change, but diffuse and increased intensity was observed for transforming growth factor-beta 3. Conclusion. Changes in the intensity of insulin-like growth factor-I and its major binding protein and the transformation of growth factor-beta 3 may play a role in the pathogenesis of preeclampsia by altering the structure and responsiveness of the umbilical cord.