Stem cell use in eye surgery

The corneal epithelium acts as a barrier to pathogens entering the eye; corneal epithelial cells are continuously renewed by uni-potent, quiescent limbal stem cells (LSCs) located at the limbus, where the cornea transitions to conjunctiva. There has yet to be a consensus on LSC markers and their transcriptome profile is not fully understood, which may be due to using cadaveric tissue without an intact stem cell niche for transcriptomics. In this study, we addressed this problem by using single nuclei RNA sequencing (snRNAseq) on healthy human limbal tissue that was immediately snap-frozen after excision from patients undergoing cataract surgery...

BACKGROUND: The major problem associated with the benign but destructive growing pterygium is the high recurrence rate. A new surgical technique to lower recurrence rates is minor ipsilateral simple limbal epithelial transplantation (mini-SLET), where the regeneration potential of limbal stem cells is used in combination with amniotic membrane transplantation (AMT) for surgical reconstruction. The aim of this study is to assess the surgical outcome of the mini-SLET technique with tenonectomy, mitomycin C, and AMT as used in the authors' hospital...

PURPOSE: This study describes the technique of simple limbal epithelial transplantation (SLET) without amniotic membrane grafting (AMG) in limbal stem cell deficiency (LSCD). METHODS: Retrospective, interventional case series of 6 patients who underwent SLET without AMG were included. The procedure followed the standard technique, involving limbal biopsy from the healthy eye, resection of symblephera, and pannus dissection in the affected eye. Following host bed preparation, limbal explants were placed on the bare cornea and secured with fibrin glue...

AIM: This study was performed to evaluate neural regenerative capacities of bone marrow stem cells (BMSCs) with or without superparamagnetic iron oxide nanoparticles (SPIONs) as a magnetic targeting tool after neurolysis of the facial nerve (FN) in albino rats. METHODS: Thirty-eight male albino rats were selected. Two of them were euthanized for normal FN histology assessment. Thirty-six rats were injected with ethanol in the FN nerve for neurolysis induction and assessed one week post-operatively by eye blinking test...

Two-photon excitation microscopy (TPM) and multiphoton fluorescence microscopy (MPM) are advanced forms of intravital high-resolution functional microscopy techniques that allow for the imaging of dynamic molecular processes and resolve features of the biological tissues of interest. Due to the cornea's optical properties and the uniquely accessible position of the globe, it is possible to image cells and tissues longitudinally to investigate ocular surface physiology and disease. MPM can also be used for the in vitro investigation of biological processes and drug kinetics in ocular tissues...

The amniotic membrane is a single epithelial layer of the placenta. It has anti-inflammatory, anti-scarring, anti-angiogenic and possibly bactericidal properties. The basement membrane of the amniotic membrane acts as a substrate to encourage healing and re-epithelialisation. It has been used in many ocular surface diseases including persistent epithelial defects (corneal or conjunctival), chemical or thermal burns, limbal stem cell deficiency, cicatrising conjunctivitis, ocular graft versus host disease, microbial keratitis, corneal perforation, bullous keratopathy, dry eye disease, corneal haze following refractive surgery and cross-linking, band keratopathy, ocular surface neoplasia, pterygium surgery, and ligneous conjunctivitis...

PURPOSE: To evaluate the incidence, clinical characteristics, microbiological profile, and therapeutic outcomes of corneal ulcers in individuals with chronic ocular graft-vs-host disease (coGVHD). DESIGN: Retrospective clinical cohort study METHODS: Review of individuals diagnosed with coGVHD following hematopoietic stem cell transplantation (HSCT) who were seen at the Bascom Palmer Eye Institute between May 2010 and November 2021. Baseline demographics, clinical characteristics, microbiological profile, risk factors for corneal ulceration, and treatment outcomes were collected...

INTRODUCTION: The aim of this work is to evaluate the effect of mesenchymal stem cell transplantation (MSCT) and cultivated limbal epithelial transplantation (CLET) therapies on the limbus of patients suffering from limbal stem cell deficiency (LSCD). METHODS: A sub-analysis of a phase I-II randomized, controlled, and double-masked clinical trial was performed to assess the changes in the anatomical structures of the limbus. In vivo confocal microscopy (IVCM) analysis was carried out in LSCD eyes before and 12 months after allogeneic MSCT or CLET...

PURPOSE: Allogenic transplantation of retinal pigmented epithelium monolayer sheet has experienced bottlenecks due to imperfect surgical techniques. In this study, we developed a novel approach for allogenic transplantation of big sheets of retinal pigment epithelium (RPE)-Bruch membrane complex. METHODS: RPE-Bruch membrane complex sheets of 5 × 6 mm2 to 10 × 10 mm2 were taken from donated eyes. Through a novel approach, the sheets of RPE-Bruch membrane complex were transplanted into the subretinal space of eight eyes (8 patients) with late-stage retinitis pigmentosa...

INTRODUCTION: We report the clinical outcome of a novel surgical technique called simple oral mucosal epithelial transplantation (SOMET) for the treatment of limbal stem cell deficiency (LSCD) in a patient with Stevens-Johnson Syndrome (SJS). PRESENTATION OF CASE: An eighteen-year-old girl was diagnosed as having chronic bilateral ocular sequelae of SJS. She initially underwent mucous membrane grafting (MMG) in both eyes for lid margin keratinization. Over the course of the next decade, the ocular surface cicatrization worsened in her left eye, leading to progressive symblepharon formation with total corneal conjunctivalization...

Sulfur mustard (SM) is a lethal chemical agent that affects many organs, particularly the eyes, respiratory system and skin. Even asymptomatic patients with documented SM vapor exposure may develop organ disorder many years later. Patients with even minor signs in the acute stage may experience late complications that necessitate surgery. Early decontamination and conservative measures could help the patients and decrease the complications. Despite decades of research, there is still no effective treatment for either acute or long-term SM-induced ocular complications...

OBJECTIVE: Stem cell therapy is a promising strategy for the treatment of corneal endothelial dysfunction, and the need to find functional alternative seed cells of corneal endothelial cells (CECs) is urgent. Here, we determined the feasibility of using the retinal pigment epithelium (RPE) as an equivalent substitute for the treatment of corneal endothelial dysfunction. METHODS: RPE cells and CECs in situ were obtained from healthy New Zealand male rabbits, and the similarities and differences between them were analyzed by electron microscopy, immunofluorescent staining, and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR)...

Limbal epithelial stem cell deficiency (LSCD) is an abnormal corneal epithelial lesion with several causes. The patient was diagnosed using fluorescein staining. Bullous keratopathy, multiple surgeries, and drug-related damage can cause LSCD in glaucoma patients. We evaluated the medical treatment course for LSCD in patients with glaucoma. We retrospectively reviewed the electronic medical records of patients diagnosed with LSCD and investigated their background, course of treatment, and classification stages of LSCD before and after treatment...

Lens itself has limited regeneration functionality, thus we aimed to create regenerated lens with biological function to treat cataracts rather than the intraocular lens used in cataract surgery. We induced exogenous human embryonic stem cells to directionally differentiate into lens fate like cells in vitro , mixed these cells with hyaluronate, and then implanted the mixture into lens capsule to regenerate in vivo . We successfully achieved near-complete lens regeneration, and the thickness of the regenerated lens reached 85% of the contralateral eye, showing the characteristics of biconvex shape, transparency, and a thickness and diopter close to that of natural lenses...

AIM: To evaluate the efficacy and safety of intrastromal transplantation of adipose-derived stem cells (ASCs) in keratoconus patients. METHODS: This study was conducted on 8 eyes of 8 patients with moderate to severe keratoconus. In the patients, ophthalmic assessments including visual acuity, refraction, slit lamp examination, fundoscopy, corneal topography, and confocal microscopy were performed. Autologous stem cells were used. The isolated stem cells were injected into the corneal stroma by using femtosecond laser...

PURPOSE: This article aims to present the corneal tattooing method and how using a tattoo pen machine can improve aesthetic appearance in patients with corneal leukoma. METHODS: In this study, 42 patients were evaluated who had no visual potential and who had undergone colored corneal tattooing using an automatic tattoo pen machine for aesthetic purposes. The procedure was conducted according to the principles of the Declaration of Helsinki. The commercially available tattoo ink that has traditionally been used on human skin (brown, green, and black) for years was used for all the patients in this study, and 252 corneal photographs (with a Topcon slit lamp imaging device at 16 magnifications, i...

PURPOSE OF REVIEW: Cell-based therapies are an exciting new frontier in managing corneal diseases. The introduction of these novel therapies may provide new alternatives to corneal transplantation and decrease the dependence on donor corneal tissue. These changes have the potential to significantly impact eye banking in the future. RECENT FINDINGS: The current article reviews current research involving cell-based therapy for treating corneal disorders, including cultivated limbal stem cell transplantation, limbal mesenchymal stem cells for stromal regeneration, and the use of human-cultivated endothelial cells...

PURPOSE: Ethanol and mitomycin C (MMC) are clinically used to treat corneal diseases such as LASEK and LASIK surgery. In this study, we investigated the effects of time-dependent alcohol and MMC in cultured rat limbal stem cells (LSCs) to determine the appropriate time for the use of this compound in the clinical setting. METHODS: LSCs (N = 10 eyes) isolated from male Wistar rats were cultured and characterized; then, isolates were divided into three groups...

Gelatinous drop-like corneal dystrophy (GDLD) is a rare autosomal recessive corneal dystrophy that has been associated with mutations in the TACSTD2 (M1S1) gene, which is normally expressed in corneal epithelial cells. GDLD is characterized by progressive deposition of amyloid in the corneal stroma with rapid recurrence in grafts after penetrating keratoplasty. We report of case of a patient with GDLD treated bilaterally with staged limbal stem cell transplantation and penetrating keratoplasty that resulted in long-term control of his disease...

INTRODUCTION: Toxic epidermal necrolysis (TEN), also known as Steven Johnson syndrome (SJS), is a devastating disease. Patients develop blindness and symblepharon despite multiple reconstructive surgeries. We report a case of SJS/TEN with ocular involvement where treatment with hyperbaric oxygen therapy (HBOT) resulted in a significant improvement in the visual acuity after surgery. CASE PRESENTATION: A woman with SJS/TEN with severe ocular complication (SOC) had limbal stem cell deficiency and symblepharon of the superior and inferior fornix...