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Mi S.,University of Reading | Mi S.,Shaanxi Institute of Ophthalmology | David A.L.,University College London | Chowdhury B.,University College London | And 4 more authors.
Tissue Engineering - Part A | Year: 2012

The aim of this study was to construct an artificial fetal membrane (FM) by combination of human amniotic epithelial stem cells (hAESCs) and a mechanically enhanced collagen scaffold containing encapsulated human amniotic stromal fibroblasts (hASFs). Such a tissue-engineered FM may have the potential to plug structural defects in the amniotic sac after antenatal interventions, or to prevent preterm premature rupture of the FM. The hAESCs and hASFs were isolated from human fetal amniotic membrane (AM). Magnetic cell sorting was used to enrich the hAESCs by positive ATP-binding cassette G2 selection. We investigated the use of a laminin/fibronectin (1:1)-coated compressed collagen gel as a novel scaffold to support the growth of hAESCs. A type I collagen gel was dehydrated to form a material mimicking the mechanical properties and ultra-structure of human AM. hAESCs successfully adhered to and formed a monolayer upon the biomimetic collagen scaffold. The resulting artificial membrane shared a high degree of similarity in cell morphology, protein expression profiles, and structure to normal fetal AM. This study provides the first line of evidence that a compacted collagen gel containing hASFs could adequately support hAESCs adhesion and differentiation to a degree that is comparable to the normal human fetal AM in terms of structure and maintenance of cell phenotype. © 2012 Mary Ann Liebert, Inc.

Hu Q.,Xiamen University | Huang C.,Xiamen University | Wang Y.,Xiamen University | Wang Y.,Shaanxi Institute of Ophthalmology | Wu R.,Xiamen University
Molecular Medicine Reports | Year: 2015

The aim of the present study was to investigate the expression of leukemia inhibitory factor (LIF) and its downstream signaling pathways in the rat retina following acute ocular hypertension. The intraocular pressure of the rats was elevated to 110 mmHg for 1 h by infusing the anterior chamber with normal saline. The retinal tissues were obtained 12 h, 24 h, and 2, 3 and 7 days after termination of the ocular hypertension. Hematoxylin and eosin and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were performed to assess the morphological changes and the apoptosis of retinal cells, respectively. Quantification of the retinal ganglion cells (RGCs) was performed using fluorogold retrograde (FG) staining. The expression levels of LIF, LIF receptor (LIFR), signal transducers and activators of transcription 3 (STAT3), phosphorylated STAT3 (P-STAT3), Akt, phosphorylated-Akt (P-Akt), extracellular signal-regulated kinase (ERK) and phosphorylated ERK (P-ERK) were determined at different time-points following acute ocular hypertension using western blot analysis. Reverse transcription-quantitative polymerase chain reaction was performned to detect the mRNA expression levels of LIF and LIFR. The results revealed that 12 h, 24 h, 2, 3 and 7 days after reperfusion, the thickness of the inner nuclear layer and the inner plexiform layer was decreased, with a significant reduction in the number of RGCs, as determined using TUNEL and FG staining. The expression levels of LIF and LIFR were increased following acute ocular hypertension. At 12 h post-retinal reperfusion, the expression levels of P-STAT3 and P-Akt were significantly upregulated, while the expression of P-ERK was decreased. The changes in the expression levels of LIF and LIFR suggested that LIF may be important in the process of degeneration/protection following retinal ischemia induced by acute ocular hypertension, via activation of the Janus kinase/STAT and Akt signaling pathways.

Mi S.,University of Reading | Khutoryanskiy V.V.,University of Reading | Jones R.R.,University of Reading | Zhu X.,Shaanxi Institute of Ophthalmology | And 2 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2011

The experiments were designed to use photochemically cross-linked plastically compressed collagen (PCPCC) gel to support corneal epithelial cells. A plastically compressed collagen (PCC) scaffold was photo cross-linked by UVA in the presence of riboflavin to form a biomaterial with optimal mechanical properties. The breaking force, rheology, surgical suture strength, transparency, ultrastructure, and cell-based biocompatibility were compared between PCPCC and PCC gels. The breaking force increased proportionally with an increased concentration of riboflavin. The stress required to reach breaking point of the PCPCC scaffolds was over two times higher compared to the stress necessary to break PCC scaffolds in the presence of 0.1% riboflavin. Rheology results indicated that the structural properties of PCC remain unaltered after UVA cross-linking. The PCC gels were more easily broken than PCPCC gels when sutured on to bovine corneas. The optical density values of PCPCC and PCC showed no significant differences (p > 0.05). SEM analyses showed that the collagen fibres within the PCPCC gels were similar in morphology to PCC gels. No difference in cell-based biocompatibility was seen between the PCPCC and PCC scaffolds in terms of their ability to support the ex vivo expansion of corneal epithelial cells or their subsequent differentiation evidenced by similar levels of cytokeratin 14. In conclusion, PCPCC scaffold is an optimal biomaterial for use in therapeutic tissue engineering of the cornea. Copyright © 2011 Wiley Periodicals, Inc.

Hui X.-Y.,Fuping Chinese Medicine Hospital | Zhang H.-B.,Shaanxi Institute of Ophthalmology
International Journal of Ophthalmology | Year: 2010

• AIM: To explore the clinical characteristics of ocular cicatricial pemphigoid, and provide assistance in clinical diagnosis and therapy. • METHODS: The data of 35 cases of ocular cicatricial pemphcgoid from January, 2002 to January, 2008 was retrospectively analyzed. • RESULTS: The average age of ocular cicatricial pemphigoid was 62.4 years, and the rate of male and female gender was 20/15. The average history was 3.3 years. The oral mucosa was firstly invaded in 51.43% patients, ocular mucosa in 31.43% ones, and other mucosa in 17.14% ones. In eye-involved patients, the rate of eyelid entropium and trichiasis, dry eye and chronic conjunctivitis, and corneopathy was 5/4/2. After treatment, 71.43% (25/35) cases were cured, while 14.29% (5/35) cases were not cured, and 14.29% (5/35)cases did not accomplished the regimen. In the course of treatment, the complications were found in 37.14% (13/35) cases, and among these, abnormal liver function was found in 6 cases and 2 cases withdrew from treatment, abnormal kidney function in 2 cases and 1 case discontinued the protocal, abnormal blood system in 3 cases and 1 case quitted the regimen, myocardial infarction in 1 case who gave up the treatment, and apparent blood hypertension in 1 case. • CONCLUSION: Cicatricial pemphigoid is a chronic ailment and often involved in the elderly. Male patients are more than female ones, and ocular tissue is often involved. Dry eye disease, Symblepharon, entropion and trichisis are all its manifestations. The treatment of cicatricial pemphigoid is complicated, and multidisciplinary collaboration is required.

Wang Y.,Xiamen University | Wang Y.,Shaanxi Institute of Ophthalmology | Xu K.,Shaanxi Institute of Ophthalmology | Zhang H.,Shaanxi Institute of Ophthalmology | And 3 more authors.
Molecular Medicine Reports | Year: 2014

Accumulative evidence has indicated that apoptosis is the common pathway for retinal ganglion cell (RGC) death and that autophagy promotes survival of RGCs in glaucoma. In the present review, it was hypothesized that the progressive death of RGCs in glaucoma involves another novel non-apoptotic programmed cell death, known as 'paraptosis', in the early stages of glaucoma. Paraptosis may be accompanied by apoptosis and/or autophagy in the moderate and severe stages. The secondary hypothesis suggests that paraptosis in glaucomatous RGCs may be triggered by damage to cellular mitochondria, and is associated with mitochondria-derived reactive oxygen species (ROS). Our preliminary laboratory studies, using transmission electron microscopy, provided evidence that supports the primary hypothesis. The secondary hypothesis is currently under investigation. These two hypotheses provide a novel way to investigate the mechanisms of cell death in glaucomatous RGCs and targeting paraptosis may be a promising strategy for RGC-protecting drug discovery.

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