Severe ocular diseases may result in partial or complete limbal cell deficiency. Besides conservative options, treatment options include conjunctival replacement procedures and limbal autografting. Limbal allografts are an option in patients with bilateral limbal cell deficiency. In many of these cases, a keratoprosthesis (KPro) is the last option to restore functional vision in patients with s...

PURPOSE To investigate the phenotype of fetal and adult human limbal cells cultured on human amniotic membrane and the ability of cultured adult human limbal cells to repair limbal stem cell deficiency in a rabbit model. METHODS Human adult and fetal limbal cells were isolated and cultured either on plastic plates or on human amniotic membrane. Connexin43, p63, and keratins 3 and 12 (K3 and K...

BACKGROUND/AIM Chemical ocular burn, especially by alkali, may result in damage to the limbal stem cells, fundamental in maintaining the integrity of ocular surface. Clinically, patients manifest abnormal conjunctival-corneal healing with peripheral neovessels, chronic epithelial defect, severe stromal inflammation, and conjunctivalisation of the corneal, which is characteristic of limbal defic...

AIMS To evaluate the distribution, morphometry and the postmortem changes of the central and peripheral human corneal nerves by exvivo laser-scanning confocal microscopy (EVCM). METHODS 24 eyes from 14 cadavers were retrieved at different time intervals after death and examined by EVCM. Five regions were examined in each eye: central, superior, inferior, temporal and nasal. In each region, co...

PURPOSE The purpose of this study was to identify phenotypic markers of human limbal stem cells in fetal and adult corneas. METHODS RNA from microscopically dissected superficial limbal and central fetal (18 weeks) corneas was amplified and used to generate P(32)-labeled, reverse-transcribed antisense RNA that was linearly amplified and hybridized to a focused stem cell cDNA microarray. Diffe...

OBJECTIVE To describe the early results of penetrating keratoplasty (PKP) in patients who had previously undergone cultivated limbal epithelium transplantation. METHODS Medical records of patients with limbal stem cell deficiency due to chemical burns who underwent PKP after cultivated limbal epithelium transplantation were reviewed for demographics, primary etiology, type of limbal transplan...

Corneal epithelium is traditionally thought to be a self-sufficient, self-renewing tissue implying that its stem cells are located in its basal cell layer. Recent studies indicate however that corneal epithelial stem cells reside in the basal layer of peripheral cornea in the limbal zone, and that corneal and conjunctival epithelia represent distinct cell lineages. These ideas are supported by ...

Limbal epithelial stem cells (LESCs) are essential to maintain the transparent ocular surface required for vision. Despite great advances in our understanding of ocular stem cell biology over the last decade, the exact location of the LESC niche remains unclear. In the present study we have used in vitro clonal analysis to confirm that limbal crypts provide a niche for the resident LESCs. We ha...

Nerve growth factor (NGF), a member of the neurotrophin family, has been identified as an essential growth factor supporting stem cell self-renewal outside the nervous system and was previously shown to stimulate corneal epithelial proliferation both in vivo and in vitro. In this study, we evaluated the expression of NGF and its corresponding receptors in the human corneal and limbal tissues, a...

Accumulating evidence supports the dogma that the corneal epithelium is regenerated by stem cells located exclusively in the limbal niche, at the corneal periphery. Accordingly, limbal stem cells (LSCs) give rise to progenitors that proliferate and migrate centripetally to repopulate the corneal epithelium, which has a short turnover. Moreover, LSC loss leads to corneal opacity and blindness, w...