Cell Populations Isolated from Amnion, Chorion, and Wharton’s Jelly of Human Placenta
Ornella Parolini, Antonietta Silini in Placenta, 2016
Amniotic membrane (or amnion) is the inner of the two fetal membranes that form the amniotic sac that surrounds and protects the fetus. Amnion is a thin, semitransparent, semipermeable and avascular membrane attached to the chorionic membrane, and it covers the entire chorionic plate, continuing over the umbilical cord with the fetal skin. This membrane is composed of two layers: an epithelial layer in direct contact with amniotic fluid and an underling mesenchymal layer attached to the chorionic membrane. The epithelial layer, named amniotic epithelium, is composed of columnar and cuboidal epithelial cells, and it is attached to a basement membrane that, in turn, is in contact with the mesenchymal layer. The latter layer is compact and composed of fibronectin and collagen (type I and III), and it hosts a network of dispersed mesenchymal cells and a rare population of macrophages. Below the mesenchymal layer, a spongy layer of collagen fibers separates amnion from chorion (Evangelista et al. 2008; Diaz-Prado et al. 2011) (Figure 5.1b top panel).
First Trimester
Swati Goyal in Essentials of Abdomino-Pelvic Sonography, 2018
Amnion and YS criteria: >7 weeks maternal age (MA)—Visualization of amnion in the absence of embryo evinces its resorption (Amnion normally develops after the embryo).Collapsing irregularly marginated amnion.YS calcification (a/w abnormal outcome) versus solid echo dense YS (live embryo). YS malformations occur in embryos of diabetic mothers in the first trimester of pregnancy <9 weeks. At 8–12 weeks, YS <2 millimeters is associated with poor outcome.On TVS—MSD >8 millimeters nonvisualization of YS.Nonvisualization of YS in the presence of embryo.At 5–10 weeks—YS diameter >5.6 millimeters.Abnormal large YS—Associated with chromosomal abnormalities (trisomy 21), partial molar pregnancy, and omphalocele.
Characterization Of Fluids And Gases
Sujoy K. Guba in Bioengineering in Reproductive Medicine, 2020
In early pregnancy the fetal skin allows fluid flow readily and the skin does not serve as a barrier to fluid movement. Amniotic fluid can in this condition be regarded as an extension of fetal extracellular fluid with the amnion as the fluid limiting membrane. Following mid gestation the fetal skin keratinizes and establishes a barrier between fetal extracellular fluid and the amniotic fluid. Composition of the amniotic fluid after this stage no longer reflects the fetal fluid compositions. Even so, a close relationship exists between fetal conditions and the composition of liquor amnii. Near term the fetus drinks about 400 ml of amniotic fluid per day and an equal volume is excreted into the amniotic cavity. Various types of cells are shed into the amniotic fluid and chemical compounds from the fetal lungs also find their way to the amniotic cavity. Abnormally, significant amounts of meconium may be passed heralding fetal distress.28 Although an indirect approach, characterization of the amniotic fluid provides valuable data from which fetal conditions may be assessed by extrapolation.
Sustained delivery of 17β-estradiol by human amniotic extracellular matrix (HAECM) scaffold integrated with PLGA microspheres for endometrium regeneration
Published in Drug Delivery, 2020
Yue Chen, Weidong Fei, Yunchun Zhao, Fengmei Wang, Xiaoling Zheng, Xiaofei Luan, Caihong Zheng
Tissue regeneration is considered to be a promising way for the treatment of IUAs. Recently, natural tissue-derived biomaterials have been increasingly applied to prevent postoperative re-adhesion (Kou et al., 2020). The amnion membrane (AM), a kind of prospective biomaterials, could not only act as a mechanical barrier to separate the wounded surface but also secrete various growth factors to activate the regulation of endometrial cell proliferation, migration, differentiation to achieve the morphological and functional recovery of the uterus (Shakouri-Motlagh et al., 2017). In the clinic, both the fresh and lyophilized amnion membranes have been used as anti-IUAs therapy (Cai et al., 2017; Li et al., 2020). However, AM may induce an immune response when integral membranes are transplanted into the majority of human tissues. Decellularized AM can reduce potential immunogenicity as the extracellular components of tissues are well tolerated even when used as xenografts (Aamodt & Grainger, 2016). In addition, by eliminating cellular components, the extracellular matrix (ECM) is more exposed, which promotes tighter cell-ECM interactions and results in more efficient cell attachment as well as stimulating different cell behaviors (Portmann-Lanz et al., 2007; Shakouri-Motlagh et al., 2017). ECM-derived scaffolds have been applied to promote the regeneration of various tissues in both preclinical and clinical types of research (Nogami et al., 2016; McQuilling et al., 2019), but there are no reports about the treatments of IUA with human amnion extracellular matrix (HAECM).
Amniotic membrane and its epithelial and mesenchymal stem cells as an appropriate source for skin tissue engineering and regenerative medicine
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Behrouz Farhadihosseinabadi, Mehrdad Farahani, Tahereh Tayebi, Ameneh Jafari, Felor Biniazan, Khashayar Modaresifar, Hamideh Moravvej, Soheyl Bahrami, Heinz Redl, Lobat Tayebi, Hassan Niknejad
Amnion membrane is the closest layer of the placenta to the fetus [14]. This layer makes direct contact with the fetus and amniotic fluid. Thus, it plays a remarkable role in development and protection of embryo [15]. This thin membrane consists of different layers and cell types which make it as a unique skin substitute (Figure 1). Generally, amnion membrane is composed of five layers including 1) epithelium layer, 2) basement membrane, 3) compact layer, 4) fibroblast layer and 5) spongy layer (Figure 2). Two cell types, extracellular matrix (ECM) proteins, and growth factors are placed in the mentioned layers [16]. The amniotic membrane includes amniotic mesenchymal cells (AMCs) and amniotic epithelial cells (AECs) which are responsible for the production of ECM, different cytokines and growth factors [16]. Amnion, as one of the oldest biomaterials, exhibits a great potential to be utilized in tissue engineering, especially for skin regeneration. Anti-bacterial [17], anti-inflammatory [18,19] and non-immunogenic properties [20] of amniotic membrane, as well as its ability to accelerate re-epithelialization [21], have been well proven in literature. Moreover, amnion-derived epithelial and mesenchymal cells possess self-renewal and differentiation characteristics [22]. These cells have several properties which make them as an appropriate cell source for stem cell therapy.
Comparative Assessment of Short-Term Tendon-Scleral Postoperative Inflammation and α-Smooth Muscle Actin Expression following Oral and Topical Diclofenac Administration for Strabismus Surgery in Rabbits
Published in Current Eye Research, 2023
Anna Puspitasari Bani, Ikhwanuliman Putera, Eka Susanto, Rina La Distia Nora
The presence of early fibrotic reaction and collagen deposition, which might arguably lead to long-term fibrosis, would contribute to a mechanical restriction that may complicate re-surgery if it is performed, particularly in complex cases. Adhesion involving muscle/tendon, sclera, and conjunctiva has been observed intraoperatively.32,33 Several experiments to prevent excessive fibrosis using rabbits have been reported prior to our study. Amnion membrane placed in the scleral bed or surrounding the recessed/resected muscle showed inconsistent results. Amnion membrane could dampen inflammation, thus reducing fibrosis.9,10 However, the occurrence of xenograft rejection had been also reported and associated with more severe inflammation and fibrosis.34 With regard to antifibrotic agents, mitomycin-C, 5-fluorouracil, infliximab, and tranilast eye drop showed promising results.11–15 Of note, these antifibrotic drugs may not always be readily available, limiting their utility in clinical settings. Hence, our study using diclofenac, which is relatively more affordable, may serve as an alternative to reduce postoperative inflammation following strabismus surgery.