Figure 4

Immunoreactivity (red colour) against IGFBP-4, −5, and PAPPA2 in the syncytiotrophoblast of first trimester placental villi. Serial cross sections of placental villi at 5 and 6 weeks of gestation (7 and 13 weeks not shown) were stained for IGFBP-4, IGFBP-5, and PAPP-A2. Negative controls used non-specific goat IgG in the place of the primary antibodies. FB = fetal blood vessel, CM = chorionic mesoderm, ST = syncytiotrophoblast. Scale bars denote 100 μm.