Regulation of the Integrin Subunit α5 Gene Promoter by the Transcription Factors Sp1/Sp3 Is Influenced by the Cell Density in Rabbit Corneal Epithelial Cells

2003 ◽  
Vol 44 (9) ◽  
pp. 3742 ◽  
Author(s):  
Marie-Eve Gingras ◽  
Kathy Larouche ◽  
Nicolas Larouche ◽  
Steeve Leclerc ◽  
Christian Salesse ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Epithelial Cells ◽  
Cell Density ◽  
Gene Promoter ◽  
Integrin Subunit ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial

scholarly journals Irradiated Human Fibroblasts as a Substitute Feeder Layer to Irradiated Mouse 3T3 for the Culture of Human Corneal Epithelial Cells: Impact on the Stability of the Transcription Factors Sp1 and NFI

2019 ◽  
Vol 20 (24) ◽  
pp. 6296
Author(s):  
Gaëtan Le-Bel ◽  
Sergio Cortez Ghio ◽  
Louis-Philippe Guérin ◽  
Francis Bisson ◽  
Lucie Germain ◽  
...  
Keyword(s):  
Stem Cells ◽  
Transcription Factors ◽  
Cell Differentiation ◽  
Dna Binding ◽  
Epithelial Cells ◽  
Stem Cell Differentiation ◽  
Feeder Layer ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial ◽  
Human Corneal Epithelial Cells

Because of the worldwide shortage of graftable corneas, alternatives to restore visual impairments, such as the production of a functional human cornea by tissue engineering, have emerged. Self-renewal of the corneal epithelium through the maintenance of a sub-population of corneal stem cells is required to maintain the functionality of such a reconstructed cornea. We previously reported an association between stem cell differentiation and the level to which they express the transcription factors Sp1 and NFI. In this study, we investigated the impact of replacing irradiated 3T3 (i3T3) murine fibroblast feeder cells by irradiated human corneal fibroblasts (iHFL) on the expression of Sp1 and NFI and evaluated their contribution to the proliferative properties of human corneal epithelial cells (hCECs) in both monolayer cultures and human tissue engineered corneas (hTECs). hCECs co-cultured with iHFL could be maintained for up to two more passages than when they were grown with i3T3. Western Blot and electrophoretic mobility shift assays (EMSAs) revealed no significant difference in the feeder-layer dependent increase in Sp1 at both the protein and DNA binding level, respectively, between HCECs grown with either i3T3 or iHFL. On the other hand, a significant increase in the expression and DNA binding of NFI was observed at each subsequent passage when hCECs were co-cultured along with i3T3. These changes were found to result from an increased expression of the NFIA and NFIB isoforms in hCECs grown with i3T3. Exposure of hCECs to cycloheximide revealed an increased stability of NFIB that likely resulted from post-translational glycosylation of this protein when these cells were co-cultured with i3T3. In addition, iHFL were as efficient as i3T3 at preserving corneal, slow-cycling, epithelial stem cells in the basal epithelium of the reconstructed hTECs. Furthermore, we observed an increased expression of genes whose encoded products promote hCECs differentiation along several passages in hCECs co-cultured with either type of feeder layer. Therefore, the iHFL feeder layer appears to be the most effective at maintaining the proliferative properties of hCECs in culture most likely by preserving high levels of Sp1 and low levels of NFIB, which is known for its gene repressor and cell differentiation properties.

scholarly journals Regulation of K3 keratin gene transcription by Sp1 and AP-2 in differentiating rabbit corneal epithelial cells.

1997 ◽  
Vol 17 (6) ◽  
pp. 3056-3064 ◽  
Author(s):  
T T Chen ◽  
R L Wu ◽  
F Castro-Munozledo ◽  
T T Sun
Keyword(s):  
Epithelial Cells ◽  
Gene Promoter ◽  
Epithelial Differentiation ◽  
Binding Motif ◽  
Basal Cells ◽  
High Concentration ◽  
Corneal Epithelial Cells ◽  
Keratin Gene ◽  
Corneal Epithelial ◽  
Basal Keratinocytes

Rabbit corneal epithelial cells cultured in the presence of 3T3 feeder cells undergo biochemical differentiation, as evidenced by their initial expression of K5 and K14 keratins characteristic of basal keratinocytes, followed by the subsequent expression of K3 and K12 keratin markers of corneal epithelial differentiation. Previous data established that mutations of an Sp1 site in a DNA element, E, that contains overlapping Sp1 and AP-2 motifs reduce K3 gene promoter activity by 70% in transfection assays. We show here that Sp1 activates while AP-2 represses the K3 promoter. Although undifferentiated corneal epithelial basal cells express equal amounts of Sp1 and AP-2 DNA-binding activities, the differentiated cells down-regulate their Sp1 activity slightly but their AP-2 activity drastically, thus resulting in a six- to sevenfold increase in the Sp1/AP-2 ratio. This change coincides with the activation and suppression of the differentiation-related K3 gene and the basal cell-related K14 keratin gene, respectively. In addition, we show that polyamines, which are present in a high concentration in proliferating basal keratinocytes, can inhibit the binding of Sp1 to its cognate binding motif but not that of AP-2. These results suggest that the relatively low Sp1/AP-2 ratio as well as the polyamine-mediated inhibition of Sp1 binding to the E motif may account, in part, for the suppression of the K3 gene in corneal epithelial basal cells, while the elevated Sp1/AP-2 ratio may be involved in activating the K3 gene in differentiated corneal epithelial cells. Coupled with the previous demonstration that AP-2 activates the K14 gene in basal cells, the switch of the Sp1/AP-2 ratio during corneal epithelial differentiation may play a role in the reciprocal expression of the K3 and K14 genes in the basal and suprabasal cell layers.

Comparison of Ocular Surface Cytological Appearance in Glaucoma Patient Treated with Timolol Maleat 0,5% Latanoprost 0,005% and Timolol-Latanoprost Fixed Combination Preservative Free Eye Drop

2019 ◽  
Vol 44 (2) ◽  
pp. 82
Author(s):  
Maretha Amrayni ◽  
Elsa Gustianty ◽  
Susi Heryati ◽  
Andika Prahasta ◽  
Maula Rifada ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cell Density ◽  
Goblet Cell ◽  
Ocular Surface ◽  
Fixed Combination ◽  
Cell Contact ◽  
Corneal Epithelial ◽  
Preservative Free ◽  
Goblet Cell Density ◽  
Epithelial Metaplasia

Introduction : The longterm use of topical antiglaucoma might cause ocular surface instability due to active substance or preservative used. Impression cytology examination may reveal superficial epithelial cells on conjunctiva and cornea, including goblet cells. Goblet cell density decrease is the most important parameter on evaluation of ocular surface disorder. Objective : This study was to understand ocular surface remodeling due to active substance of topical antiglaucoma with impression cytology examination among the patient prior and 3 months after therapy. Methods : This was a randomized controlled trial study with single blind masking. A total of 45 eyes from 31 patients were used as subject and distributed onto three groups treatment, which were timolol maleat 0.5%, latanoprost 0.005%, and latanoprost-timolol maleat fixed combination. All topical antiglaucoma in this study were preservative free. Result : There were differences between 3 groups in goblet cells density after 3 months therapy (p=0,030). Goblet cell density in timolol group was lower than latanoprost (p=0,041) and fixed combination (p=0,045). There was no significantly difference between 3 groups in conjunctival epithelial metaplasia degree (p=0,706) and cell to cell contact degree in corneal epithelial cells (p=0.66) after 3 months therapy. Conjunctival epithelial metaplasia degree were increased among group of timolol (p=0,008) and fixed combination (p=0,046). Conclusion : Timolol maleat 0,5% caused lower goblet cell density after 3 months therapy compare with latanoprost and fixed combination. There was no significantly difference in conjunctival epithelial metaplasia and cell to cell contact degree in corneal epithelial cells among these glaucoma treatment groups.

Carboxymethyl β-glucan Binds to Corneal Epithelial Cells and Increases Cell Adhesion to Laminin and Resistance to Oxidative Stress

Cornea ◽  
2007 ◽  
Vol 26 (1) ◽  
pp. 73-79 ◽  
Author(s):  
Marco Porcu ◽  
Francesco Guarna ◽  
Laura Formentini ◽  
Giuseppe Faraco ◽  
Silvia Fossati ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Adhesion ◽  
Epithelial Cells ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial

In Vitro Toxicity of Netilmicin and Ofloxacin on Corneal Epithelial Cells

Cornea ◽  
2003 ◽  
Vol 22 (5) ◽  
pp. 468-472 ◽  
Author(s):  
Anna Claudia Scuderi ◽  
Grazia Maria Paladino ◽  
Clara Marino ◽  
Francesco Trombetta
Keyword(s):  
Epithelial Cells ◽  
In Vitro Toxicity ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial

Recombinant TIMP-1 and -2 enhance the proliferation of rabbit corneal epithelial cells in vitro and the spreading of rabbit corneal epithelium in situ

1998 ◽  
Vol 17 (1) ◽  
pp. 47-52 ◽  
Author(s):  
Shizuya Saika ◽  
Yoshiji Kawashima ◽  
Yuka Okada ◽  
Sai-Ichi Tanaka ◽  
Osamu Yamanaka ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Corneal Epithelium ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial

Role of TREM-1 in response to Aspergillus fumigatus infection in corneal epithelial cells

2014 ◽  
Vol 23 (1) ◽  
pp. 288-293 ◽  
Author(s):  
Li-ting Hu ◽  
Zhao-dong Du ◽  
Gui-qiu Zhao ◽  
Nan Jiang ◽  
Jing Lin ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Aspergillus Fumigatus ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial
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