Umbilical Amnion Research Articles

The Use of Umbilical Amnion for Conjunctival Socket, Fornix, and Eyelid Margin Reconstruction.

To describe outcomes using umbilical amnion for conjunctival fornix, socket, and eyelid margin reconstruction. A medical record review was performed to identify patients who had received umbilical amnion over a 2-year period in their department. Patient demographics, disease etiology, and data regarding surgical outcomes were collected. The primary outcome was the success rate of the surgical intervention. Twenty-one patients received umbilical amnion for anophthalmic socket contracture (n = 16), orbital implant exposure (n = 3), ocular surface burn (n = 1), and cicatricial entropion repair (n = 1). The primary outcome was met in 76% of patients overall. In anophthalmic socket contracture, the primary outcome was met in 86% and 0% of patients with acquired and congenital anophthalmia, respectively. The primary outcome was met in all cases of orbital implant exposure and cicatricial entropion. The primary outcome was not met in a Roper-Hall grade IV ocular surface burn. Umbilical amnion is an ideal substrate graft for reconstruction of the conjunctival fornix, socket, and eyelid margin. Umbilical amnion appears to be efficacious for the management of socket contracture in acquired anophthalmia, orbital implant exposure, and cicatricial entropion. Further experience is needed to determine the efficacy of umbilical amnion in ocular surface burns.

Region-Specific Gene Expression Profiling: Novel Evidence for Biological Heterogeneity of the Human Amnion1

The amnion plays an important role during pregnancy and parturition. Though referred to as a single structure, this fetal tissue is regionally divided into placental amnion, reflected amnion, and umbilical amnion. Histological differences between placental amnion and reflected amnion led us to hypothesize that the amnion is biologically heterogeneous. The gene expression profiles of placental amnion and reflected amnion were compared in patients at term with no labor (TNL; n = 10) and in labor (TIL; n = 10). Real-time quantitative RT-PCR revealed a higher expression of IL1B mRNA in reflected amnion than in placental amnion in TNL cases but not in TIL cases. Extended screening using microarrays showed differential expression of 17 genes in labor, regardless of the region. Interestingly, 839 genes were differentially expressed between placental amnion and reflected amnion. Pathway analysis identified 19 signaling pathways, such as mitogen-activated protein kinase and transforming growth factor beta pathways, associated with region. Lipopolysaccharide (LPS) treatment of the amnion explants showed more robust activation of mitogen-activated protein kinase 3/1 (extracellular signal-regulated kinase 1/2) in placental amnion of TNL but not in TIL cases. Placental amnion from TNL and TIL cases showed a significant difference in the amplitude of IL1B mRNA induction by LPS. We report that the anatomical region has a substantial impact on the transcriptional program and the biological properties of the amnion. Labor-associated switching to a proinflammatory signature is a feature particular to placental amnion. The novel observations herein strongly suggest that the seemingly homogeneous amnion is biologically heterogeneous and compartmentalized, with implications for the physiology of pregnancy and parturition.

Evidence for the presence of luteinizing hormone-chorionic gonadotrophin receptors in the pig umbilical cord.

Pig umbilical cord, like that of humans, contains two arteries and a vein surrounded by Wharton's jelly with amnion covering the exterior surface. The aim of the present study was to investigate whether LH-hCG receptors are present in the pig umbilical cord, using light microscope immunohistochemistry, semiquantitative autoradiography, western blotting and reverse transcription-polymerase chain reaction. Umbilical cords were collected on days 48, 71 and 103 of fetal life (n = 6). Monoclonal and polyclonal anti-LH receptor antibodies were used to study receptor distribution. Immunoreactivity was observed in the umbilical blood vessels, the epithelium of umbilical amnion and cells in the Wharton's jelly. No differences in LH-hCG receptor distribution related to the sex of the fetus, period of fetal life or section of the umbilical cord were observed. Strong immunostaining was observed in umbilical vein and in umbilical arteries. However, in the arteries, the tunica media expressed weaker receptor immunostaining than did the tunica intima and tunica adventitia. No immunoactivity was detected in non-target tissue (skeletal muscle) but LH receptors were immunostained in the pig ovary. Topical autoradiography showed that vein and arteries in the umbilical cord bind 125I-labelled hCG, which was highly diminished after co-incubation with an excess of unlabelled hCG. The binding of 125I-labelled hCG to the Wharton's jelly and epithelial amnion was less intense than it was to vessels. Gonadotrophin binding sites were not present in the skeletal muscle. The pig umbilical arteries, vein and Wharton's jelly contained a 75 kDa immunoreactive LH-hCG receptor protein similar to that found in corpora lutea. Southern blot analysis of reverse transcription-polymerase chain reaction products, performed to enhance the sensitivity and specificity of LH receptor transcripts determination in umbilical cord tissues, revealed that the expected fragments of 740 and 470 bp were present in the arteries, vein, Wharton's jelly and corpora lutea (positive control). An additional product of 670 bp was found in the corpora lutea and arteries of umbilical cord, but not in the vein and Wharton's jelly. This is probably the first reported evidence of the presence of LH-hCG receptors in the umbilical cord of a non-human female mammal.

Expression of epidermal growth factor, transforming growth factor-alpha, and their common receptor genes in human umbilical cords.

Epidermal growth factor (EGF) and transforming growth factor-alpha (TGF alpha), present in amniotic fluid and/or in fetal blood, could potentially regulate cord functions. The present study investigated the possible presence of functional receptors and EGF and TGF alpha themselves in umbilical cord. The reverse transcription-polymerase chain reaction followed by Southern blotting demonstrated that human umbilical cords contain EGF, TGF alpha, and EGF/TGF alpha messenger ribonucleic acid (mRNA) transcripts. In situ hybridization revealed that these mRNA transcripts are present in vascular endothelial cells and smooth muscle, amnion, and myofibroblasts in Wharton's jelly. Western immunoblotting showed that the cords contain a 170-kilodalton EGF/TGF alpha receptor protein. Immunocytochemistry demonstrated that all of the cells that contained mRNA transcripts also contained corresponding proteins. Umbilical amnion contains more EGF, TGF alpha, and their receptors than any other part of the cord. In the cord, the fetal and middle portions contain more than the placental portion or the vessels inside the placental tissue. The cord receptors can bind [125I]EGF, stimulate receptor autophosphorylation, and increase cyclooxygenase-1 and -2 and prostaglandin E2, suggesting that the receptors are functional. In summary, our study demonstrates that human umbilical cord expresses EGF, TGF alpha, and their common receptor genes. The cord EGF/TGF alpha receptors are functional in terms of binding of EGF, activation of receptor autophosphorylation, and increasing the formation of vasoconstrictive eicosanoid. Thus, EGF, TGF alpha, and their receptors could be one of the determinants of human fetal growth and development by autocrine, paracrine, and endocrine actions in umbilical cord.

Novel expression of functional human chorionic gonadotropin/luteinizing hormone receptor gene in human umbilical cords.

Human umbilical cord contains two arteries and a vein surrounded by Wharton's jelly with amnion covering the exterior surface. The cord blood and amniotic fluid contain human CG (hCG). Whether hCG can directly regulate cord functions is unknown. We now report that human umbilical cords contain a major 4.4-kilobase and minor 2.6- and 1.8-kilobase hCG/LH receptor messenger RNA transcripts. The cords also contain a 50-kilodalton immunoreactive receptor protein which can bind hCG and LH, but not hFSH or hTSH. Rat testis used as a positive tissue control contained the same major and minor receptor transcripts and an 80-kilodalton receptor protein which can bind [125I]hCG. Rat liver used as a negative control contained neither receptor transcripts nor receptor protein. The smooth muscle and endothelial cells of umbilical arteries and vein, umbilical amnion, and cells in Wharton's jelly contain the receptor transcripts and receptor protein which can bind [125I]hCG. The receptor expression was higher in umbilical vessels closer to the baby and decreased toward placenta, becoming barely detectable once the vessels were inside the placental tissue. In vitro treatment of umbilical cords with highly purified hCG resulted in an increase of immunoreactive cyclooxygenase-1, cyclooxygenase-2, prostacyclin synthase, and 6-keto-prostaglandin F1 alpha, little change in thromboxane A2 synthase and a decrease of prostaglandin E2 and thromboxane B2 as compared to the controls, indicating that the cord receptors are functional. In summary, these novel findings suggest that hCG present in cord blood and amniotic fluid may directly regulate the vascular tone and quite possibly other functions of human umbilical cord.