Figure 2.

A comparison of placental development in pigs created by SCNT. A,B: Histological sections comparing the fetal maternal interface at Day 35 of gestation between normal in vivo (IVV) (A) and SCNT (B). Sections are stained with hematoxylin and eosin and show similar structural morphology between the two. C,D: Immunohistochemistry with primary antibodies specific to porcine pregnancy-associated glycoprotein-2 (pPAG2). The IVV section (C) shows a clear delineation between the trophoblast (TE) and luminal epithelium (LE) at the microvillar junction (MVJ) with PAG2 protein specific to the placental side. The SCNT section (D) shows a premature accumulation of PAG2 at the microvillar junction and even transversing into the maternal LE. This observation has only been observed in SCNT sections. E: Both PAG2 message, measured by real-time PCR relative to a reference cDNA and housekeeping gene (YWHAG, described previously Whitworth et al., 2005), and its associated acid peptidase activity (Telugu and Green, 2008) were decreased in placentas derived from SCNT when compared to IVV (P <0.05). F: Miniature piglet created by treating reconstructed SCNT zygotes with the HDACi, Scriptaid which has been shown to improve cloning efficiency. G,H: Fetuses and their associated extraembryonic membranes derived from SCNT (G) compared to their in vivo counterparts (H) collected at Day 30 of gestation. Notice all 4 IVV extraembryonic membranes have an established vasculature and the placentas are much larger (H) than from SCNT. All microscopic images were obtained with a 40× objective.