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1.
Rev. bras. oftalmol ; 79(1): 71-80, Jan.-Feb. 2020. tab, graf
Article in Portuguese | LILACS | ID: biblio-1092653

ABSTRACT

Resumo Atualmente a membra amniótica (MA) tem obtido importância devido à comprovada capacidade de reduzir inflamação, auxiliar a cicatrização e epitelização, possuindo propriedades antimicrobianas e antivirais, além de baixa imunogenicidade. As indicações de seu uso na oftalmologia têm aumentado muito nas duas últimas décadas. Objetivo: Descrever a estrutura básica e as propriedades biológicas da MA em relação aos componentes da sua matriz extracelular e fatores de crescimento, as consequências de diferentes técnicas empregadas na sua preservação e esterilização, métodos para remoção do epitélio e a comparação dos custos dos diferentes meios de conservação atualmente empregados. Métodos: Pesquisa nas bases de dados do Portal da Biblioteca Virtual em Saúde (BVS), Pubmed, Cochrane, Scielo e Lilacs com as palavras-chave: membrana amniótica, transplante, reconstrução da córnea, doenças da conjuntiva. Resultados: A literatura é vasta na descrição dos efeitos de diversos agentes e técnicas na preparação da MA, dentre elas sua preservação, esterilização e desepitelização. A membrana desnuda tem sido a escolha para a reconstrução da superfície ocular, pois facilita a cicatrização. Em relação aos agentes conservantes, o glicerol é o meio mais utilizado mundialmente pelo baixo custo e facilidade de manuseio. Conclusão: A comparação das diversas técnicas nos guia na elaboração de protocolos de preparo da MA para uso oftalmológico. A membrana desnuda facilita a cicatrização em relação a com células epiteliais. O glicerol é o meio de conservação mais utilizado pelo baixo custo e facilidade de manuseio.


Abstract Currently, the amniotic membrane (AM) has obtained importance due to its ability to reduce inflammation, helping in the healing and epithelialization processes, having antimicrobial and antiviral properties and low immunogenicity. Its indications in ophthalmology have increased considerably in the past two decades. Objective: To describe the basic structure and biological properties of the AM, the components of the extracellular matrix and growth factors, the consequences of different techniques used in its preservation, and sterilization methods for the epithelium removal. To compare the costs of the different preservation solutions currently employed. Study design: literature review. Methods: Research in BVS databases, PubMed, Cochrane, Scielo and Lilacs with keywords: amniotic membrane transplantation, corneal reconstruction, conjunctival diseases. Results: The literature is vast in describing the effects of different agents and techniques used in the preparation of MA, including its preservation, sterilization and desepithelization. The naked membrane is the choice to reconstruct the ocular surface, as it facilitates the healing course. Regarding the preservatives, glycerol is the most used worldwide due its low cost and easy handling. Conclusion: Comparing different techniques guides us in developing a MA preparation protocol for ophthalmic use. The naked membrane facilitates the healing process compared with the presence of epithelial cells. The glycerol is the most used preservation method because of its low cost and easy handling.


Subject(s)
Humans , Tissue Preservation/methods , Conjunctival Diseases/surgery , Corneal Diseases/surgery , Tissue and Organ Harvesting/methods , Eye Diseases/surgery , Amnion/transplantation , Tissue Banks/standards , Tissue Donors/supply & distribution , Wound Healing , Biological Dressings/standards , Biological Products/standards , Tissue and Organ Procurement/standards , Cryopreservation/methods , Sterilization/methods , Collagen/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Extracellular Matrix/metabolism , Amnion/cytology , Amnion/microbiology , Amnion/ultrastructure
2.
Biol. Res ; 48: 1-8, 2015. ilus, graf
Article in English | LILACS | ID: biblio-950833

ABSTRACT

BACKGROUND: Human amnion mesenchymal cells (hAMCs), isolated from the amniotic membrane of human placenta, are a unique population of mesenchymal stem cells. Recent studies demonstrated that hAMCs could inhibit the activities and functions of several immune cells. However, their effect on inflammatory macrophages is largely unknown. This study investigated the effect of hAMCs on expression of inflammatory cytokines and mitogen-activated protein kinases (MAPKs)/NF-kB pathway in human THP-1 macrophages induced by lipopolysaccharide (LPS). RESULTS: The levels of TNF-α and IL-1ß secreted by LPS- stimulated THP-1 cells were increased significantly compared with those in the control group. After co-culture with different numbers of hAMCs, the levels of TNF-α and IL-1ß in LPS-stimulated THP-1 cells were significantly reduced compared with the LPS group. The mRNA expression of TNF-α and IL-1ß were also markedly inhibited. Moreover, treating LPS-stimulated THP-1 cells with hAMCs supernatants could also suppress TNF-α and IL-1ß production in THP-1 cells. Important signaling pathways involved in the production of TNF-α and IL-1ß were affected by hAMCs co-culture: hAMCs remarkably suppressed NF-kB activation and down-regulated the phosphorylation of ERK and JNK in LPS- stimulated THP-1 cells. CONCLUSIONS: Human amnion mesenchymal cells inhibited the production of TNF-α and IL-1ß secreted by LPS-stimulated THP-1 cells, partly through the suppression of NF-kB activation and ERK and JNK phosphorylation.


Subject(s)
Humans , Lipopolysaccharides/pharmacology , Tumor Necrosis Factor-alpha/biosynthesis , Interleukin-1beta/biosynthesis , Mesenchymal Stem Cells/physiology , Amnion/cytology , Macrophages/metabolism , Tumor Necrosis Factor-alpha/drug effects , MAP Kinase Signaling System/drug effects , Interleukin-1beta/drug effects
3.
Article in English | WPRIM | ID: wpr-169633

ABSTRACT

Recent studies have shown that mesenchymal stem cells (MSCs) are able to differentiate into multi-lineage cells such as adipocytes, chondroblasts, and osteoblasts. Amniotic membrane from whole placenta is a good source of stem cells in humans. This membrane can potentially be used for wound healing and corneal surface reconstruction. Moreover, it can be easily obtained after delivery and is usually discarded as classified waste. In the present study, we successfully isolated and characterized equine amniotic membrane-derived mesenchymal stem cells (eAM-MSCs) that were cultured and maintained in low glucose Dulbecco's modified Eagle's medium. The proliferation of eAM-MSCs was measured based on the cumulative population doubling level (CPDL). Immunophenotyping of eAM-MSCs by flow cytometry showed that the major population was of mesenchymal origin. To confirm differentiation potential, a multi-lineage differentiation assay was conducted. We found that under appropriate conditions, eAM-MSCs are capable of multi-lineage differentiation. Our results indicated that eAM-MSCs may be a good source of stem cells, making them potentially useful for veterinary regenerative medicine and cell-based therapy.


Subject(s)
Adipogenesis , Amnion/cytology , Animals , Cell Differentiation , Cell Lineage , Cell Proliferation , Chondrogenesis , Female , Flow Cytometry/veterinary , Horses , Immunophenotyping/veterinary , Mesenchymal Stem Cells/cytology , Osteogenesis
4.
Article in English | WPRIM | ID: wpr-219417

ABSTRACT

This study was performed to evaluate the effects of conditioned media (CM) from human amniotic epithelial cells (HAECs) on the corneal wound healing process. Eighteen rabbits (36 eyes) were used and randomly assigned to three groups according treatment: CM from HAECs (group 1), vehicle alone (group 2), and saline (group 3). Corneal alkali injuries were induced with 1 N sodium hydroxide. Each reagent used for treatment evaluation was injected into the dorsal bulbar subconjunctiva and the area of the corneal epithelial defect was measured every other day. Two animals from each group were euthanized at a time on days 3, 7, and 15, and the cornea was removed for histological examination. The sum of the epithelial defect areas measured on day 0 to day 6 as well as day 0 to day 14 in group 1 was significantly smaller than those of other groups. Histological examination revealed that the group 1 corneas had less inflammatory cell infiltration and showed more intact epithelial features compared to the other groups. These results suggest that CM from HAECs promote corneal wound healing in rabbits.


Subject(s)
Alkalies/toxicity , Amnion/cytology , Animals , Cornea/injuries , Corneal Diseases/chemically induced , Culture Media, Conditioned/pharmacology , Epithelial Cells/physiology , Humans , Male , Rabbits
5.
Article in English | WPRIM | ID: wpr-13096

ABSTRACT

Human amniotic membrane-derived mesenchymal stem cells (hAM-MSCs) are capable of differentiating into several lineages and possess immunomodulatory properties. In this study, we investigated the soluble factor-mediated immunomodulatory effects of hAM-MSCs. Mitogen-induced peripheral blood mononuclear cell (PBMC) proliferation was suppressed by hAM-MSCs in a dose-dependent manner as well as hAM-MSC culture supernatant. Moreover, interferon-gamma and interleukin (IL)-17 production significantly decreased from PBMC, whereas IL-10 from PBMCs and transforming growth factor beta (TGF-beta) production from hAM-MSCs significantly increased in co-cultures of hAM-MSCs and PBMCs. Production of several MSC factors, including hepatocyte growth factor (HGF), TGF-beta, prostaglandin E2 (PGE2), and indoleamine 2, 3 dioxygenase (IDO), increased significantly in hAM-MSCs co-cultured with PBMCs. These results indicate that the immunomodulatory effects of hAM-MSCs may be associated with soluble factors (TGF-beta, HGF, PGE2, and IDO), suggesting that hAM-MSCs may have potential clinical use in regenerative medicine.


Subject(s)
Amnion/cytology , Cell Differentiation/immunology , Coculture Techniques , Dinoprostone/genetics , Female , Hepatocyte Growth Factor/genetics , Humans , Immunologic Factors/immunology , Immunophenotyping , Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics , Interferon-gamma/immunology , Interleukin-10/analysis , Interleukin-17/analysis , Leukocytes, Mononuclear/cytology , Mesenchymal Stem Cells/cytology , Pregnancy , RNA, Messenger/chemistry , Regenerative Medicine/methods , Reverse Transcriptase Polymerase Chain Reaction , Transforming Growth Factor beta/genetics
6.
Qom University of Medical Sciences Journal. 2011; 4 (4): 37-47
in Persian | IMEMR | ID: emr-110579

ABSTRACT

Recently, interest has increased in the potential employment of embryonic stem cells for the treatment of Parkinson's disease, which has been considered as an alternative therapeutic strategy. Due to their pluripotent differentiation potential, the finding that they do not induce carcinoma and the fact that they do not raise the ethical concerns connected with human embryonic stem cells, human amniotic epithelial cells are considered to be a very promising cell source. The aim of this study was to investigate the effects of FGF8 and Shh on the expression of dopaminergic markers from human amniotic epithelial cells. In this study, we examined the differentiation of dopaminergic neurons in vitro from AECs using the expression of several markers including TH, DAT and D beta H. For dopaminergic differentiation, sonic hedgehog [Shh] and FGF8 were added to cultures and the cultures were allowed to differentiate for 21 days. Analysis of AECs derived dopaminergic neurons was performed at the TH, DAT, beta-tubulin III and D beta H expression levels by immunocitochemistry. The significance of the data was tested by Student's t-test [between two groups] and one-way analysis of variance [ANOVA] followed by Tukey post-test. [p<0/01, p<0/05]. Combination of Shh and FGF8 showed the higher level of TH in comparison to control group or these factors alone. Moreover, Shh is more effective than FGF8 on DAT expression in comparison to expression of D beta H. These results show the capability of AECs to express dopaminergic neural markers and this ability is affected by Shh and FGF8


Subject(s)
Humans , Embryonic Stem Cells , Fibroblast Growth Factor 8 , Hedgehog Proteins , Dopamine Agents , Amnion/cytology
7.
Biocell ; 33(2): 81-89, Aug. 2009. ilus, tab
Article in English | LILACS | ID: lil-595032

ABSTRACT

By virtue of expressions of glial and neural surface markers and capability of neurotransmitter metabolism, amniotic epithelial cells are considered as candidate cell type for transplantation strategies to treat neurological disorders. Previously, we have reported neurotrophism exhibited by human amniotic epithelial cells when transplanted after spinal cord injury in bonnet monkeys. Amniotic epithelial cells were believed to secrete an "Epidermal Growth Factor (EGF)-like" factor and exact identification was not made. At this juncture, through the present study it was found that, chicken neural retinal cells when grown alone failed to survive and contrarily when either co-cultured with chicken amniotic epithelial cells/cultured in amniotic epithelial cell conditioned medium not only survived but also showed extensive differentiation. Fibroblast Growth Factor-2 (FGF-2) plays a critical role in retinal development especially in chicken neural retinal development. However, immunoassay using western blot did not revealed the presence of any already known isoforms of FGF-2 in the medium. It is interesting to note that while factor secreted by amniotic epithelial cells resembles EGF and/or FGF-2 in its biological action, known isoforms of them were not detected. Considering the biological closeness between EGF and FGF-2, results indicate the possibility of a novel isoform of these growth factors secreted by amniotic epithelial cells. Further studies will establish the nature of this novel factor which will enhance the application of this interesting cell type for neural transplantations.


Subject(s)
Humans , Animals , Amnion/cytology , Epithelial Cells , Fibroblast Growth Factor 2 , Epidermal Growth Factor/genetics , Epidermal Growth Factor/metabolism , Nerve Growth Factors , RNA, Messenger/genetics , RNA, Messenger/metabolism , Blotting, Western , Cell Differentiation , Cell Survival , Chickens
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