Injectable candidate sealants for fetal membrane repair: bonding and toxicity in vitro.

Objective: This study was undertaken to test injectable surgical sealants that are biocompatible with fetal membranes and that are to be used eventually for the closure of iatrogenic membrane defects.

Study Design: Dermabond (Ethicon Inc, Norderstedt, Germany), Histoacryl (B. Braun GmbH, Tuttlingen, Germany), and Tissucol (Baxter AG, Volketwil, Switzerland) fibrin glue, and 3 types of in situ forming poly(ethylene glycol)-based polymer hydrogels were tested for acute toxicity on direct contact with fetal membranes for 24 hours.

Relation between mechanical properties and microstructure of human fetal membranes: an attempt towards a quantitative analysis.

Objective: We sought to measure the mechanical baseline behavior of fetal membranes in order to determine constitutive mechanical model parameters for fetal membranes, and to examine their relation to molecular correlates for mechanical function, i.e. collagen and elastin.

Comparative characterization of cultured human term amnion epithelial and mesenchymal stromal cells for application in cell therapy.

Emerging evidence suggests human amnion tissue as a valuable source of two distinct types of pluripotent cells, amnion epithelial cells (hAECs) and mesenchymal stromal cells (hAMSCs), for applications in cell replacement therapy. For some approaches, it may be necessary to culture and differentiate these cells before they can be transplanted. No systematic attempt has been yet made to determine the quantity and quality of amnion cells after isolation and culture.

Fetoscopic closure of punctured fetal membranes with acellular human amnion plugs in a rabbit model.

Objective: To explore a surgical plug formed from decellularized term human amnion membrane for fetoscopic closure of iatrogenic defects in fetal membranes in a rabbit model.

Methods: The study was performed in eight rabbit does. Punctures were created at midgestational day 23 by 14-gauge needle fetoscopy on surgically exposed rabbit amniotic sacs.

Concise review: isolation and characterization of cells from human term placenta: outcome of the first international Workshop on Placenta Derived Stem Cells.

Placental tissue draws great interest as a source of cells for regenerative medicine because of the phenotypic plasticity of many of the cell types isolated from this tissue. Furthermore, placenta, which is involved in maintaining fetal tolerance, contains cells that display immunomodulatory properties. These two features could prove useful for future cell therapy-based clinical applications.

The Young's modulus of fetal preterm and term amniotic membranes.

Objective: To examine the Young's modulus of the human amniotic membranes, as well as its relationship to gestational age. To determine whether cellular and material-related parameters affect this modulus.

Study Design: In a prospective study at the Obstetric outpatient clinic of the University Hospital Zurich Young's modulus, thickness and mesenchymal:epithelial cell ratio of amniotic membranes of preterm (N=23) and term (N=40) placentae were examined.

Human preterm amnion cells cultured in 3-dimensional collagen I and fibrin matrices for tissue engineering purposes.

Objective: In this study, human preterm amnion cells were investigated in 3-dimensional (3D) cell-matrix culture systems in an attempt to design therapeutic strategies for preterm premature rupture of the membranes.

Study Design: Three-dimensional collagen I and fibrin cell-containing biomatrices were created to mimic the architecture of native amnion. Amnion mesenchymal cells were embedded in 3D matrices, and epithelial cells were placed on top of these matrices.

In vitro lesion repair by human amnion epithelial and mesenchymal cells.

Objective: The purpose of this study was to compare wound healing by human amnion epithelial and mesenchymal cells from preterm and term placenta with the use of an in vitro lesion repair assay.

Study Design: Lesions were created in confluent monolayers of amnion epithelial and mesenchymal cells from preterm and term placentas. The repair was monitored by the measurement of the lesion area and the response to potential stimulants (platelet-derived growth factor, tumor necrosis factor-alpha, fibrinogen, and phorbol myristate acetate).

Inducing proliferation of human amnion epithelial and mesenchymal cells for prospective engineering of membrane repair.

Objective: To prepare a tissue engineering approach to fetal membrane repair after premature rupture of the membranes (PROM) by characterizing the proliferation potential of human amnion epithelial and mesenchymal cells from preterm and term placenta in primary culture.

Methods: Amnion epithelial and mesenchymal cells from 15 preterm (23-36 week) and 27 term placentas collected at cesarean section were separated enzymatically, characterized immunohistochemically (anti-cytokeratin 18 and anti-E-cadherin, and anti-vimentin, respectively), and their ratio determined. Proliferation on tissue culture polystyrene (TCPS) or collagen in one medium and on TCPS in four different media after 14 days was measured photometrically and compared in preterm vs.

Renal tubular epithelial expression of the costimulatory molecule B7RP-1 (inducible costimulator ligand).

MHC class II-expressing renal tubular epithelial cells (TEC) are able to present foreign peptide antigens to T cells. The costimulatory signals that are required for effective T cell activation upon antigen presentation by TEC have not been characterized. Various cultured TEC lines were examined for expression of the recently described costimulatory molecule B7RP-1 (B7h), a ligand of the T cell molecule inducible costimulator (ICOS), and expression was compared with that of B7.