Using Amniotic Membrane as the Carrier for ex Vivo Cell Culture for Cell Therapy in Ocular Surface Reconstruction
试验速览
- 阶段
- 不适用
- 入组人数
- 50
- 试验地点
- 1
研究概览
简要总结
The use of amniotic membrane in ophthalmic surgery has been shown to provide an alternative for corneal and conjunctival reconstruction in many clinically challenging situations. It has without doubt provided an option where previously none existed in some conditions. Nevertheless, it is has its limitations and is not universally successful for every indication. The indications for its use are ever increasing, often on anecdotal evidence. In some instances where it is successfully used, existing and at times simpler options are equally effective. The collective global experience with the membrane is now vast, and the field should now move into proper randomized controlled studies to evaluate its true potential.
详细描述
Human amniotic membrane (AM) is composed of three layers: a single epithelial layer, a thick basement membrane, and an avascular stroma. The amniotic membrane was first used along with the chorion as a biologic membrane to promote healing of skin burns in 1910. In ophthalmology, it was used in 1940 in the management of conjunctival defects. Its revival in the 1990s was due to its ability to reduce ocular surface inflammation and scarring, promote rapid epithelialization due to the presence of growth factors, and antimicrobial properties.1,2 The amniotic membrane is a biologic tissue that has been used as a graft for corneal and conjunctival reconstruction in a variety of ocular surface diseases. It is avascular and possesses anti-angiogenetic, anti-scarring and antiinflammatory properties. It is not a substitute but rather a substrate upon which cells can migrate and regenerate, forming new and healthy tissue.2 Amniotic membrane has several properties and is extremely useful in ocular surgery2,3:
- Promotes Epithelialization:
Amniotic membrane acts like a basement membrane and facilitates the migration of epithelial cells.4 It reinforces adhesion of basal epithelial cells, promotes epithelial differentiation, prevents epithelial apoptosis, and improves corneal sensitivity and tear film stability,5 although the exact mechanism is not known. It also produces growth factors that promote epithelial cell growth.6 It is believed to expand and maintain epithelial progenitor cells ex vivo.7 2. Inhibits Fibrosis:
Fibroblasts are normally responsible for the scarring associated with wound healing and are activated by transforming growth factor TGF-β. Amniotic membrane downregulates TGF-βand the receptor expression by fibroblasts and thus reduces fibrosis. Choi and Tseng 8,9 implanted dispase-treated amniotic membrane with and without cultured rabbit corneal epithelial cells intrastromally into rabbit corneas. They observed that the amniotic membrane alone did not induce keratocyte differentiation into myofibroblasts and the cornea remained clear. Amniotic membrane also suppressed the TGF-β signaling in corneal and limbal fibroblasts and in conjunctival and pterygial fibroblasts.10 3. Antiinflammatory and Antiangiogenic Factors:
There are several reports of reduction of inflammation with amniotic membrane.11 The exact mechanism is not known. The amniotic membrane probably acts as a barrier against the tear film resulting in a reduced amount of inflammatory cells and hence the amount of inflammatory mediators.12 In addition, the presence of proteinase inhibitors may promote healing. 4. Antimicrobial and Antiviral Properties:
研究设计
- 研究类型
- Observational
入排标准
- 年龄范围
- 18 Years 至 50 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Pregnant women from 18 to 50 years take cesarean section. No HIV, HBV, HCV, syphilis.
排除标准
- •Positive reaction to HIV, HBV, HCV, syphilis. Have Significant disease.
研究者
National Taiwan University Hospital
Wei-Li Chen/Assistant Professor, National Taiwan University, Department of Ophthalmology.
National Taiwan University Hospital