One of the main goals of tissue engineering and regenerative medicine is to develop skin substitutes for treating deep dermal and full thickness wounds. In this regard, both scaffold and cell source have a fundamental role to achieve exactly the same histological and physiological analog of skin. Amnion epithelial and mesenchymal cells possess the characteristics of pluripotent stem cells which have the capability to differentiate into all three germ layers and can be obtained without any ethical concern. Amniotic cells also produce different growth factors, angio-modulatory cytokines, anti-bacterial peptides and a wide range of anti-inflammatory agents which eventually cause acceleration in wound healing. In addition, amniotic membrane matrix exhibits characteristics of an ideal scaffold and skin substitute through various types of extracellular proteins such as collagens, laminins and fibronectins which serve as an anchor for cell attachment and proliferation, a bed for cell delivery and a reservoir of drugs and growth factors involved in wound healing process. Recently, isolation of amniotic cells exosomes, surface modification and cross-linking approaches, construction of amnion based nanocomposites and impregnation of amnion with nanoparticles, construction of amnion hydrogel and micronizing process promoted its properties for tissue engineering. In this manuscript, the recent progress was reviewed which approve that amnion-derived cells and matrix have potential to be involved in skin substitutes; an enriched cell containing scaffold which has a great capability to be translated into the clinic.

Amniotic membrane and its epithelial and mesenchymal stem cells as an appropriate source for skin tissue engineering and regenerative medicine.

Human amniotic epithelial cells induce apoptosis of cancer cells: a new anti-tumor therapeutic strategy.

Burn injuries have been reported to be an important cause of morbidity and mortality and they are still considered as unmet clinical need. Although there is a myriad of effective stem cells that have been suggested for skin regeneration, there is no one ideal scaffold. The aim of this study was to develop a three-dimensional (3D) bi-layer scaffold made of biological decellularized human amniotic membrane (AM) with viscoelastic electrospun nanofibrous silk fibroin (ESF) spun on top. The fabricated 3D bi-layer AM/ESF scaffold was submerged in ethanol to induce β-sheet transformation as well as to get a tightly coated and inseparable bi-layer. The biomechanical and biological properties of the 3D bi-layer AM/ESF scaffold were investigated. The results indicate significantly improved mechanical properties of the AM/ESF compared with the AM alone. Both the AM and AM/ESF possess a variety of suitable adhesion cells without detectable cytotoxicity against adipose tissue-derived mesenchymal stem cells (AT-MSCs). The AT-MSCs show increased expression of two main pro-angiogenesis factors, vascular endothelial growth factor and basic fibroblast growth factor, when cultured on the AM/ESF for 7 days, when comparing with AM alone. The results suggest that the AM/ESF scaffold with autologous AT-MSCs has excellent cell adhesion and proliferation along with production of growth factors which serves as a possible application in a clinical setting for skin regeneration.

/pdf/silk-fibroin-amniotic-membrane-3d-bi-layered-artificial-skin-ave5j1hsv7.pdf

Silk fibroin/amniotic membrane 3D bi-layered artificial skin

Background:Amniotic membrane (AM)–derived products have been successfully used in ophthalmology, plastic surgery, and wound care, but little is known about their potential applications in orthopaedic sports medicine.Purpose:To provide an updated review of the basic science and preclinical and clinical data supporting the use of AM-derived products and to review their current applications in sports medicine.Study Design:Systematic review.Methods:A systematic search of the literature was conducted using the Medline, EMBASE, and Cochrane databases. The search term amniotic membrane was used alone and in conjunction with stem cell, orthopaedic, tissue engineering, scaffold, and sports medicine.Results:The search identified 6870 articles, 80 of which, after screening of the titles and abstracts, were considered relevant to this study. Fifty-five articles described the anatomy, basic science, and nonorthopaedic applications of AM-derived products. Twenty-five articles described preclinical and clinical trials o...

Human Amniotic Membrane–Derived Products in Sports Medicine Basic Science, Early Results, and Potential Clinical Applications

Amniotic membrane (AM), the nearest layer of fetal membranes to the fetus, contains two types of cells with unique characteristics that make them excellent candidates for clinical applications. Amniotic epithelial and mesenchymal cells have low immunogenicity, anti-inflammation, anti-fibrosis and anti-bacterial properties and no ethical issues. Although amniotic cells have stem cell properties and express transcription factors specific for pluripotent stem cells, they are not tumorigenic after transplantation. In the last decade, a new line of research has been initiated with a focus on the anti-proliferative effects of amniotic epithelial and mesenchymal cells on tumor growth. Amnion-derived epithelial and mesenchymal cells inhibit tumor growth and invasion through three pathways: the induction of apoptosis, the stimulation of cell-cycle arrest and the inhibition of angiogenesis. In this review, the various aspects of the anti-cancer properties of amnion-derived cells and the underlying mechanisms are discussed with emphasis on the translation of the cell therapy of cancer from experimental into clinical practice.

Induction of apoptosis, stimulation of cell-cycle arrest and inhibition of angiogenesis make human amnion-derived cells promising sources for cell therapy of cancer.

G. Paeini-Vayghan

Papers

Side dependent effects of the human amnion on angiogenesis.