Fibronectin degradation by MMP-2/MMP-9 in the serum of pregnant women and umbilical cord with Toxoplasma gondii infection

It has been suggested that in congenital Toxoplasma gondii infections, the parasite reaches the fetus by crossing the placental barrier. The purpose of this study was to determine the possible relationships between matrix metalloproteinases (MMPs) and dysfunction of the placental barrier in gravidas infected with T. gondii. We studied 26 umbilical cord sera; 20 and 6 were derived from gravidas seropositive for anti-T. gondii IgG and seropositive for anti-T. gondii IgM (low IgG avidity), respectively. Of 20 cord blood samples, 18 were seropositive for T. gondii IgG, whereas all cord blood samples were seronegative for T. gondii IgM. The other six sera were seronegative for T. gondii IgG, whereas three of six sera were seropositive for T. gondii IgM. Furthermore, T. gondii induced an increase in MMP-2 and -9 secretion in the sera of gravidas and umbilical cords. Moreover, MMP-2 and -9 were interacted with fibronectin. We propose that MMP-2 and -9 may be involved in ECM degradation and placental barrier dysfunction, which facilitates T. gondii transmission to the fetus. Future investigations of the effect of MMPs on migration across epithelial and endothelial barriers will be important to establish the mechanism of transit.