Search results for "corneal epithelium"
showing 7 items of 17 documents
Patterns of cytokeratin and vimentin expression in the human eye
1988
We studied the expression of the various cytokeratin (CK) polypeptides and vimentin in tissues of the human eye by applying immunocytochemical procedures using a panel of monoclonal antibodies as well as by performing biochemical analyses of microdissected tissues. Adult corneal epithelium was found to contain significant amounts of the cornea-specific CKs nos. 3 and 12 as well as CK no. 5, and several additional minor CK components. Among these last CKs, no. 19 was found to exhibit an irregular mosaic-like staining pattern in the peripheral zone of the corneal epithelium, while having a predominantly basal distribution in the limbal epithelium. Both the fetal corneal epithelium and the con…
KLEIP Deficiency in Mice Causes Progressive Corneal Neovascular Dystrophy
2012
PURPOSE. The BTB-kelch protein KLEIP/KLHL20 is an actin binding protein that regulates cell-cell contact formation and cell migration. The aim of our study was to characterize KLEIP’s function in ocular health and disease in mice. METHODS. KLEIP -/- mice were generated, and corneas were examined histologically and stained for keratin-1, loricrin, keratin-12, keratin-14, CD31, LYVE-1, F4/80, E-cadherin, and Ki67. Corneal abrasions were performed after eyelid opening. RESULTS. Corneas of KLEIP þ/þ and KLEIP -/- mice were indistinguishable at birth. After eyelid opening corneal epithelial hyperplasia started to manifest in KLEIP -/- mice, showing a progressive epithelial metaplasia leading to …
Corneal Epithelial Stem Cells-Physiology, Pathophysiology and Therapeutic Options.
2021
In the human cornea, regeneration of the epithelium is regulated by the stem cell reservoir of the limbus, which is the marginal region of the cornea representing the anatomical and functional border between the corneal and conjunctival epithelium. In support of this concept, extensive limbal damage, e.g., by chemical or thermal injury, inflammation, or surgery, may induce limbal stem cell deficiency (LSCD) leading to vascularization and opacification of the cornea and eventually vision loss. These acquired forms of limbal stem cell deficiency may occur uni- or bilaterally, which is important for the choice of treatment. Moreover, a variety of inherited diseases, such as congenital aniridia…
Conjunctival Sac Fluid Contains Elevated Levels of Soluble TRAIL: Implications for the Anti-Tumoral Surveillance of the Anterior Surface of the Eye
2008
Little is known on the ability of different epithelia to release soluble TNF-related apoptosis-inducing ligand (TRAIL) and the relevance of TRAIL secretion by epithelial cells is still incompletely understood. On these bases, we have measured the concentration of soluble TRAIL by ELISA in the conjunctival sac fluid. It was the highest ever detected in a biological fluid (mean value of 26,800 pg/ml), being approximately 20-fold greater than that found in human saliva and >200-fold greater than that detected in human serum. On the other hand, osteoprotegerin, the soluble decoy receptor of TRAIL, was almost undetectable in the conjunctival sac fluid. Of note, the levels of soluble TRAIL measur…
Presbyopia and the aging eye: Existing refractive approaches and their potential impact on dry eye signs and symptoms.
2020
Every part of the human body is subject to aging, including the eye. Increased prevalence of dry eye disease with age is widely acknowledged: aging threatens ocular surface homeostasis, altering the normal functioning of the lacrimal functional unit and potentially leading to signs and symptoms of dry eye. Parallelly, two additional degenerative processes take place within the crystalline lens, leading to presbyopia and cataractogenesis. With continuously increasing life expectancies both conditions are expected to impact society further. Correction strategies for presbyopia and cataracts either directly or indirectly challenge ocular surface additionally. On one hand, contact lens presbyop…
Ocular gelling microspheres: in vitro precorneal retention time and drug permeation through reconstituted corneal epithelium.
2008
Purpose: The model drug norfloxacin (NOR)was encapsulated into trehalose (TRH) and hydroxyethylcellulose(NAT) microspheres to obtain a novel gelling ophthalmic delivery system for prolonged release on corneal tissue. Methods: We assessed NOR release from microspheres, prepared by the emulsion-solvent evaporation method. A new in vitro tear turnover model, including inserts containing reconstituted human corneal epithelium (RHC), was designed to evaluate the TRH/NAT microspheres’ precorneal retention time. Bioadhesive properties of TRH/NAT microspheres were validated by using drug-loaded microspheres prepared with gelatine (GLT) commonly used as reference material in adhesion studies. Result…