scholarly journals An Analysis of the Progression of Conjunctivalisation after Transplantation of Cultivated Corneal Epithelium

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Dariusz Dobrowolski ◽  
Boguslawa Orzechowska-Wylegala ◽  
Bogumil Wowra ◽  
Ewa Wróblewska-Czajka ◽  
Maria Grolik ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Corneal Epithelium ◽  
Autologous Transplantation ◽  
Corneal Surface ◽  
Corneal Epithelial ◽  
Limbal Stem Cell ◽  
Epithelial Sheets ◽  
Long Term Observation

Purpose. To analyse the recurrence of superficial neovascularisation after previous corneal surface reconstruction with cultivated corneal epithelial cells. Materials and Methods. Forty-eight eyes underwent autologous transplantation of cultivated corneal epithelium to treat partial or total limbal stem cell deficiency caused by chemical or thermal injury. The carrier for the epithelial sheets was a denuded amniotic membrane. Follow-up was conducted for up to 120 months. Recurrent revascularisation (measured in terms of clock hours affected) was evaluated with slit-lamp examination and the support of confocal microscopy. Results. During the long-term observation, only 7 eyes had stable epithelia with no neovascularisation from the conjunctiva. Nineteen eyes developed pathologic vessels in 1 quadrant, with additional 4 eyes developing them in 2 quadrants. Twelve patients developed subtotal or total conjunctivalisation of the corneal surface. They were referred for second cultivated epithelium transplantation (3 patients), allogenic keratolimbal transplantation (7 patients), or keratoprosthesis (2 patients). Six patients withdrew consent. The use of confocal scans of up to 100 µm in resolution enabled the detection of pathologic microvasculature originating from the conjunctiva and the exclusion of stromal vascular ingrowth. Conclusions. Local ingrowth of the conjunctiva is a common complication after the transplantation of cultivated epithelial cells. Severe and progressive vascularisation inevitably leads to graft failure. However, if local ingrowth stops before reaching the central cornea, the treatment even with this complication can be considered a success.

scholarly journals Avtologni veznično-limbalni presadek pri enostranskem popolnem pomanjkanju limbalnih epitelnih matičnih celic

2017 ◽  
Vol 86 (7-8) ◽  
Author(s):  
Petra Schollmayer ◽  
Zala Lužnik
Keyword(s):  
Stem Cells ◽  
Surgical Technique ◽  
Corneal Epithelium ◽  
Ocular Surface ◽  
Autologous Transplantation ◽  
Corneal Transplantation ◽  
Epithelial Stem Cells ◽  
Corneal Surface ◽  
Limbal Transplantation

Background: Corneal epithelium is renewed by stem cells (SC) that reside at the corneal limbus. Reduced number of SC or their abnormal function lead to the ocular surface disease called limbal stem cell deficiency (LSCD), characterized by corneal conjunctivalization, vascularization, persistent epithelial defects, chronic inflammation, and loss of vision. In a case of total unilateral LSCD, autologous transplantation of limbal epithelial stem cells (LESC) from the healthy eye is needed. We describe the surgical technique of choice for autologous limbal transplantation, called conjunctival limbal autograft (CLAU) that we combined with amniotic membrane (AM) use. We present the results of CLAU in three patients with total unilateral LSCD due to chemical injury.Methods: Autologous limbal transplantation CLAU begins with the removal of fibrovascular pannus from the diseased corneal surface and the harvesting of two conjunctival-limbal grafts from the healthy eye. The grafts are then transplanted on to the limbal area of the recipient eye. AM is used as a patch to cover the denuded cornea and limbal grafts, as well as a barrier preventing the conjunctival epithelium from encroaching on to the temporal and nasal side of the corneal surface. In the donor eye, AM is used to cover the donor sites. CLAU with the use of AM was performed in 3 patients with unilateral LSCD due to chemical eye injury. In one patient limbal transplantation was combined with symblepharon lysis for entropium repair. In all cases AM was removed 3–6 days postoperatively to assess the growth of new epithelium from the limbal grafts. In all patients the ocular surface was covered with another AM until the cornea was completely epithelized and the new epithelium stable. In one patient the corneal regrafting and cataract removal was performed subsequently.Results: CLAU was successful in 2 patients and partially successful in 1 patient during the follow up. In all cases the growth of new epithelium from the limbal grafts was noted on day 3–6 after CLAU. The cornea was completely epithelized within 2 weeks in 2 patients and after 35 days in one patient. In two patients the corneal epithelium remained clear, smooth and stable during the follow up of 3.5 years and 4 months, respectively. In one patient, uneven epithelium probably representing a mosaic of corneal and conjunctival cells was noted in the central corneal region, where a small corneal ulcer developed 5 months after CLAU. In donor eyes no postoperative complications were noted, the donor sites epithelized within few days.Conclusions: Autologous limbal transplantation according to CLAU surgical technique combined with the use of AM is a successful and safe therapy for restoring corneal surface in total unilateral LSCD after chemical injury. It enables further surgical procedures for restoring the vision such as corneal transplantation and cataract surgery.

scholarly journals Efficacy of Modified Amnion-Assisted Conjunctival Epithelial Redirection (ACER) for Partial Limbal Stem Cell Deficiency

Medicina ◽  
2021 ◽  
Vol 57 (4) ◽  
pp. 369
Author(s):  
Sang Beom Han ◽  
Farah Nur Ilyana Mohd Ibrahim ◽  
Yu-Chi Liu ◽  
Jodhbir S. Mehta
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Epithelial Cells ◽  
Limbal Stem Cell Deficiency ◽  
Limbal Stem Cells ◽  
Corneal Surface ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial ◽  
Limbal Stem Cell ◽  
Conjunctival Epithelial Cells

Background and objectives: the aim of this study was to analyze the efficacy of a modified “amnion-assisted conjunctival epithelial redirection (ACER)” technique for the treatment of partial limbal stem cell deficiency (LSCD). Materials and methods: the medical records of three patients with partial LSCD who underwent corneal surface reconstruction with modified ACER following superficial keratectomy were retrospectively studied. Briefly, in this technique, an inner amniotic membrane (AM) layer was applied on the corneal surface to promote corneal re-epithelialization. The outer AM layer was applied as a barrier to prevent the invasion of conjunctival epithelial cells into the cornea before the corneal surface was completely covered by corneal epithelial cells derived from the remaining intact limbal stem cells. Results: in all three cases, the outer AM layer successfully kept the conjunctival epithelium away from the corneal surface and prevented an admixture of conjunctival epithelial cells with corneal epithelial cells. In all three patients, the cornea was completely re-epithelized with epithelial cells derived from the remaining healthy limbal stem cells, and a clear visual axis was maintained without recurrence for a mean follow-up period of 37.3 ± 8.6 months. Conclusions: the preliminary results suggest that modified ACER appears to be a viable option for patients with partial LSCD.

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

scholarly journals Loss of FOXC1 contributes to the corneal epithelial fate switch and pathogenesis

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Mingsen Li ◽  
Liqiong Zhu ◽  
Jiafeng Liu ◽  
Huaxing Huang ◽  
Huizhen Guo ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Corneal Epithelium ◽  
Corneal Ulcer ◽  
Corneal Epithelial ◽  
Ocular Development ◽  
Rieger Syndrome ◽  
Corneal Ulcers ◽  
Epithelial Homeostasis ◽  
Forkhead Box ◽  
Interferon Regulatory Factor 1

AbstractForkhead box C1 (FOXC1) is required for neural crest and ocular development, and mutations in FOXC1 lead to inherited Axenfeld–Rieger syndrome. Here, we find that FOXC1 and paired box 6 (PAX6) are co-expressed in the human limbus and central corneal epithelium. Deficiency of FOXC1 and alternation in epithelial features occur in patients with corneal ulcers. FOXC1 governs the fate of the corneal epithelium by directly binding to lineage-specific open promoters or enhancers marked by H3K4me2. FOXC1 depletion not only activates the keratinization pathway and reprograms corneal epithelial cells into skin-like epithelial cells, but also disrupts the collagen metabolic process and interferon signaling pathways. Loss of interferon regulatory factor 1 and PAX6 induced by FOXC1 dysfunction is linked to the corneal ulcer. Collectively, our results reveal a FOXC1-mediated regulatory network responsible for corneal epithelial homeostasis and provide a potential therapeutic target for corneal ulcer.

scholarly journals The core planar cell polarity gene, Vangl2 , directs adult corneal epithelial cell alignment and migration

2016 ◽  
Vol 3 (10) ◽  
pp. 160658 ◽  
Author(s):  
Amy S. Findlay ◽  
D. Alessio Panzica ◽  
Petr Walczysko ◽  
Amy B. Holt ◽  
Deborah J. Henderson ◽  
...  
Keyword(s):  
Cell Migration ◽  
Epithelial Cells ◽  
Cell Polarity ◽  
Corneal Epithelium ◽  
Planar Cell Polarity ◽  
Corneal Epithelial Cell ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial ◽  
The Core

This study shows that the core planar cell polarity (PCP) genes direct the aligned cell migration in the adult corneal epithelium, a stratified squamous epithelium on the outer surface of the vertebrate eye. Expression of multiple core PCP genes was demonstrated in the adult corneal epithelium. PCP components were manipulated genetically and pharmacologically in human and mouse corneal epithelial cells in vivo and in vitro . Knockdown of VANGL2 reduced the directional component of migration of human corneal epithelial (HCE) cells without affecting speed. It was shown that signalling through PCP mediators, dishevelled, dishevelled-associated activator of morphogenesis and Rho-associated protein kinase directs the alignment of HCE cells by affecting cytoskeletal reorganization. Cells in which VANGL2 was disrupted tended to misalign on grooved surfaces and migrate across, rather than parallel to the grooves. Adult corneal epithelial cells in which Vangl2 had been conditionally deleted showed a reduced rate of wound-healing migration. Conditional deletion of Vangl2 in the mouse corneal epithelium ablated the normal highly stereotyped patterns of centripetal cell migration in vivo from the periphery (limbus) to the centre of the cornea. Corneal opacity owing to chronic wounding is a major cause of degenerative blindness across the world, and this study shows that Vangl2 activity is required for directional corneal epithelial migration.

Long-term effectiveness and safety of antiepileptic drugs in children and adults

2021 ◽  
Vol 19 (2) ◽  
pp. 221-228
Author(s):  
Roza M. Shaimardanova ◽  
Rimma G. Gamirova
Keyword(s):  
Valproic Acid ◽  
Antiepileptic Drugs ◽  
Focal Epilepsy ◽  
City Hospital ◽  
Long Term Follow Up ◽  
Short And Long Term ◽  
Long Term Observation ◽  
Patients With Epilepsy

AIM: To conduct a retrospective comparative analysis of the efficacy and safety of epilepsy therapy with antiepileptic drugs. MATERIALS AND METHODS: The analysis of the treatment of 428 patients with epilepsy at the Childrens City Hospital No. 8 in Kazan, receiving antiepileptic drugs. RESULTS: It was found that valproic acid is more effective in the treatment of idiopathic generalized epilepsies compared to focal epilepsies (p = 0.0006). Valproate and carbamazepine were the most effective in the treatment of focal epilepsy with short- and long-term follow-up. Valproic acid is more effective than topiramate (p = 0.02), oxcarbazepine (p = 0.003), and levetiracetam (p = 0.003) in the treatment of focal epilepsy in short- and long-term follow-up. Carbamazepine is more effective than topiramate (p = 0.01), oxcarbazepine (p = 0.02), and levetiracetam (p = 0.001) in the treatment of focal epilepsy in long-term follow-up. It was revealed that more often they complained about side effects when using carbamazepine (63.2%). Levetiracetam was found to be better tolerated compared to valproate (p = 0.0006) and carbamazepine (p = 0.0006). Topiramate is better tolerated than carbamazepine (p = 0.02) and valproate (p = 0.03). Oxcarbazepine is better tolerated than carbamazepine in women (p = 0.04). CONCLUSIONS: When choosing an antiepileptic drug, it is necessary to be guided by the principle: first the basic, and then the drugs of the next generations, in the future, rely on information about the tolerability of the drug. It is necessary to evaluate the therapeutic effect of antiepileptic drugs with long-term observation, and use the criterion of complete absence of seizures as an indicator of the effectiveness of drugs.

Cornea and Lens Problems in Aniridia

2010 ◽  
Author(s):  
Edward J. Holland ◽  
Mayank Gupta
Keyword(s):  
Stem Cells ◽  
Epithelial Cells ◽  
Corneal Epithelium ◽  
Basal Layer ◽  
Limbal Stem Cells ◽  
Corneal Epithelial Cells ◽  
Film Stability ◽  
Corneal Epithelial ◽  
Corneal Erosion ◽  
Peripheral Cornea

The corneal epithelium is a rapidly regenerating, stratified squamous epithelium. Homeostasis of corneal epithelial cells is an important prerequisite, not only for the integrity of the ocular surface, but also for the visual function. The maintenance of a healthy corneal epithelium under both normal and wound-healing conditions is achieved by a population of stem cells located in the basal layer of limbal epithelium. The Limbus represents the transition zone between the peripheral cornea and the bulbar conjunctiva. The stem cells from the limbus generate the transient amplifying cells that migrate, proliferate, and differentiate to replace lost or damaged corneal epithelial cells. In patients with aniridia, there is a primary dysfunction of these limbal stem cells (see Figure 6.1). The cornea is affected clinically in 90 percent of the patients with aniridia. In most cases, the cornea in aniridic patients appears normal and transparent during infancy and childhood. However, during the early teens, the cornea begins to show changes. The early changes are marked by the in-growth of opaque epithelium from the limbal region into the peripheral cornea, which represents conjunctival epithelial cells, goblet cells, and blood vessels in the corneal epithelium. These changes gradually progress toward the central cornea and may cause corneal epithelial erosions and epithelial abnormalities that eventually culminate in opacification of the corneal stroma, which leads to vision loss. With the gradual loss of limbal stem cells, the entire cornea becomes covered with conjunctival cells. Eventually, many patients develop total limbal stem cell deficiency. These abnormalities usually become more pronounced with aging. The corneal abnormalities seen in aniridia are collectively termed “aniridic keratopathy”. Significant corneal opacification may occasionally be the initial manifestation of aniridia. Abnormal tear film stability and meibomian gland dysfunction are also observed in patients with aniridia. This can lead to dry eyes, aggravating corneal erosion and ulceration observed in aniridic patients. Sometimes, aniridia is associated with “Peter’s anomaly,” in which central corneal opacity is present at birth along with defects in the corneal endothelium and Descemet’s membrane.

The Immunohistochemical Characterisation of an SV40-immortalised Human Corneal Epithelial Cell Line

2003 ◽  
Vol 31 (4) ◽  
pp. 409-417 ◽  
Author(s):  
Anne Huhtala ◽  
Sami K. Nurmi ◽  
Hanna Tähti ◽  
Lotta Salminen ◽  
Päivi Alajuuma ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Single Cell ◽  
Cell Line ◽  
Cell Cultures ◽  
Corneal Epithelium ◽  
Culture Medium ◽  
Corneal Epithelial Cell ◽  
Cell Type ◽  
Corneal Epithelial ◽  
Single Cell Type

Alternatives to the Draize rabbit eye irritation test are currently being investigated. Because of morphological and biochemical differences between the rabbit and the human eye, continuous human cell lines have been proposed for use in ocular toxicology studies. Single cell-type monolayer cultures in culture medium have been used extensively in ocular toxicology. In the present study, an SV40-immortalised human corneal epithelial (HCE) cell line was characterised immunohistochemically, by using 13 different monoclonal antibodies to cytokeratins (CKs), ranging from CK3 to CK20. The results from the monolayer HCE cell cultures were compared with those from the corneal epithelium of human corneal cryostat sections. Previous studies have shown that the morphology of the HCE cell is similar to that of primary cultured human corneal epithelial cells, and that the cells express the cornea-specific CK3. In the study reported here, we show that the cell line also expresses CKs 7, 8, 18 and 19. These CKs are typically expressed by simple epithelial cells, and are not found in the human cornea in vivo. Therefore, the monolayer HCE cell line grown in culture medium does not express the CK pattern that is typical of human corneal epithelium. This should be taken into consideration when using HCE cell cultures in similar single cell-type experiments for ocular toxicology.

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