Faculty of Medical and Health Sciences


Cornea and Stem Cells Research Projects

1. Stem Cells

Stem cell isolation and cultivation


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Jane McGhee

Our research group, led by Professor Trevor Sherwin, has for many years been interested in isolating cells from the corneas of both healthy and dystrophic (keratoconic) donors. We have isolated primary epithelial and keratocyte cell lines and latterly, Jane McGhee has developed techniques that produce stem cell enriched spheres. These spheres can be transplanted on to a variety of surfaces, including denuded donor tissue and collagen coated plastic and have been shown to be capable of repopulating these surfaces.

This research has led to 8 publications in peer reviewed journals and two chapters in recently published text books, one on the pathogenesis of Keratoconus and the other titled “Corneal Regeneration ­ Therapy and Surgery”.

Jane is also involved in translational research for the treatment of Limbal Stem Cell Deficiency (LSCD), wherein she cultivates corneal limbal stem cells harvested from patients’ corneas and expands this population of cells in vitro. These are then transplanted onto the damaged corneal surface of the patient to re-establish a healthy corneal epithelium.

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Limbal stem cell deficiency
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Following PKP and stem cell transplant

Stem cell-enriched spheres and corneal repopulation


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Salim Ismail

Our work in this area involves the characterisation of stem cell enriched spheres in terms of their cellular composition, their ability to respond to stimuli by cell migration, proliferation and differentiation and their resulting ability to repopulate and/or repair the corneal surface.  Salim Ismail has developed methods in the laboratory for fluorescent biomarker labelling and tracking of these stem cell enriched spheres to monitor the cell migration patterns and utilises time lapse microscopy to analyse cell proliferation and cell interactions.

This work also involves the use of immunocytochemistry and gene expression analysis to detect the presence and quantify the amount of stem cell and differentiation markers.  Salim has been key to developing qPCR and droplet digital PCR methods for characterising the gene expression patterns of ocular cell isolates.

Sphere cell migration, FUCCI labelling, Green = dividing cells, Red = migratory cells
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Stem cell sphere formation in vitro

Umbilical cord stem cells in eye diseases


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Anannya Parvathi

Anannya is a PhD scholar with the Faculty of Medical and Health Sciences at the University of Auckland and has a successful research track record with 8+ years' experience in projects of ocular and mesenchymal stem cells. She was instrumental in bringing out the first commercial cell therapy product in one of India's largest stem cell-based companies. She is thorough in stem cell cultivation techniques, cGMP manufacturing of cell therapy products, and related regulatory affairs. Anannya has done her bachelor's in biotechnology and has a master's in clinical research and Regulatory Affairs. Her experience is an excellent fit for the research team led by Professor Trevor Sherwin at the University of Auckland. Prof. Sherwin's laboratory focuses on the use of adult stem cells for ocular repair. The team has devised an extremely exciting project to move the research stream forward. Anannya's PhD project is under the supervision of Professor Trevor Sherwin, Professor Charles McGhee, and Mrs Jane McGhee.

Project Details: Cell-based therapies for corneal repair have extensively focussed on using corneal adult stem cells. We are investigating the use of umbilical cord stem cells, which are non-corneal and much “younger” than the fully developed adult stem cells in treating ocular surface disorders. The umbilical cord is a rich source of stem cells and is often discarded post-delivery. Worldwide, researchers are using umbilical cord stem cells to study its ability to differentiate into other cell types. The research project focuses on a) novel techniques for the extraction of different umbilical stem cell types b) different strategies for transforming/differentiating the umbilical cord stem cells into other cell types that may be beneficial in restoring sight. To date, we have worked on sheep and human cord samples. This study primarily focuses on the cornea, which is a crucial eye compartment. The encouraging results from the preliminary studies conducted on the sheep umbilical cord and its application on sheep cornea ex-vivo have set the foundation for the research on human samples.

Optimising umbilical cord stem cells for the treatment of corneal endothelial disorders


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Anmol Sandhu

As part of our research, we are currently investigating the therapeutic potential of umbilical cord stem cells in regard to corneal repair. The umbilical cord is the structure which connects the foetus to the placenta, allowing nutrients and waste to be transported between the mother and foetus. Recently, the umbilical cord has been identified as a rich source of stem cells: cells which have the capability to give rise to almost any cell type and tissue in the body, due to their undifferentiated state and ability to self-renew. Through my research, I am exploring the restorative abilities of human umbilical vein endothelial cells (HUVECs): a population of stem cells found in the umbilical vein. As these cells are of the endothelial cell lineage, it is predicted that they will differentiate into and function like corneal endothelial cells, and hence be capable of repairing the damaged corneal endothelium. A stem cell treatment for corneal endothelial disorders (such as Fuchs endothelial corneal dystrophy - FECD), will transform the medical treatment of blindness, allowing individuals with vision loss to regain their sight and improve their quality of life.

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Human umbilical cord

Optimising umbilical cord mesenchymal stem cells for the treatment of keratoconus


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Vicky Wen

In addition to the ongoing investigation in human umbilical vein endothelial cells for treating corneal endothelial disorders, we are also exploring the use of human umbilical cord mesenchymal stem cells to treat keratoconus. Keratoconus is a disease that leads to bilateral thinning of the cornea and formation of a cone shape. A significant hallmark of this disease is a progressive loss of keratocytes.

The average length of an umbilical cord is 60cm with a range of 15cm to 130cm. This long structure has an abundant number of mesenchymal stem cells (MSCs) within its gelatinous matrix that can differentiate into various cell types – including keratocytes that have a mesenchymal origin. My research explores the MSC distribution profile and their differentiation potentials along the umbilical cord to optimise their recovery. Optimised MSC isolation will provide keratoconic patients with alternative treatments such as keratocyte replacement and artificial stroma transplantations, combating the global lack of corneal donor tissue.

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Corneal stem cells as a model for ageing differences in males and females


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Sasheen Dowlath

As a joint venture under Professor Trevor Sherwin (Ophthalmology) and Dr Julie Lim (Physiology), my research aims to understand the effects of ageing on corneal stem cell repair. Previous work from the Sherwin group has shown significant differences in the potency and activity of female-derived stem cell spheres compared to their male counterparts. Previous work from the Lim group has demonstrated that mice deficient in the cysteine/glutamate antiporter (xCT-) exhibit accelerated age-related pathologies. By marrying the two independent observations, it is hypothesised that some differences may exist in the ability for male tissue and stem cells to alleviate oxidative stress. The xCT- mouse model enables us to test this hypothesis by comparing oxidative stress in wild types against knockouts from both sexes, which we hope will provide some insight as to aging differences in human males and females.

Differences between males and females in the ageing process of limbal epithelial stem cells (LESCs) in the cornea


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Fay Abdul Ghani

I am a biomedical science (honours) student currently conducting a research project investigating the differences between males and females in the ageing process of limbal epithelial stem cells (LESCs) in the cornea. LESCs contain high proliferative potential and facilitate competent corneal restoration and repair, vital for vision. Previous animal studies have shown sex-based discrepancies in the regenerative potential of stem cells in different tissues. Unfortunately, there is limited knowledge on the mechanisms that drive these differences. However, the cornea is an excellent model to explore this, given that it is a highly regenerative tissue and contains a population of stem cells which play an important role in the maintenance and regeneration of the epithelium. A potential mechanism in the cornea is the sex-specific regulation of DNA damage and reactive oxygen species (ROS).

Therefore, my research focuses on comparing the LESCs of young (6 week-old) and ageing (9 month-old) mice corneas to study whether sex specific regulation of DNA damage and ROS levels are key to stem cell ageing and decline. Overall, determining the mechanisms behind the observed difference in regenerative ability of female and male ocular stem cells from the limbus may help define the role of sex in stem cell ageing and demonstrate the potential for stem cell therapy in regeneration of the ocular surface.

2. Cell Reprogramming

Transformation of adult cells into stem-like and ocular cells


Carole Greene, Kushant Kapadia, Professor Colin Green

Cell reprogramming has made the transformation of adult cells back into cells with stem cell like properties, called induced Pluripotent Stem Cells or iPSCs, which have the potential to replace diseased cells in eye tissues, restore normal anatomy and rescue the function of the tissue restoring sight. Further to this we are also investigating in situ cell reprogramming where we use exogenous factors to trigger memories of stem cell like properties within the existing cells within the tissues. This in situ reprogramming enables the cells within the tissue to turn back the clock to a developmental phase and themselves take on the restorative properties of stem cells.

This work to date has resulted in 3 research publications in peer reviewed journals, a patent application and a book chapter.

3. Bioengineering

Lens crystallin protein films as ocular cell carriers


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Judith Glasson

Working in collaboration with Professor Trevor Sherwin (Department of Ophthalmology) and Dr Laura Domigan (Department of Chemical and Material’s Engineering), my work focuses on the design and characterisation of biomaterials for ophthalmic use. Specifically, we have developed a thin film biomaterial from the lens crystallin proteins of Hoki fish eye lenses to be used as a replacement for amniotic membrane as a carrier for limbal stem cells in the treatment of limbal stem cell deficiency. The benefits of our material over amniotic membrane include superior mechanical properties for surgical manipulation, excellent optical clarity, reduced risk of disease transmission, and simple production and storage. It is also an excellent cell carrier, proliferating both a diverse and differentiated cell population, whilst maintaining and proliferating the limbal stem cell populations.

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8cm casting of CP-GA showing transparency and mechanical properties that allow for the material to be self-supporting and easily manipulated in a surgical setting
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Example of four formulations of lens crystallin protein films, showing optical transparency even at 3x normal working thickness

4. Corneal Dystrophies

Imaging and biomarker analysis of dystrophic corneal tissue


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Judy Loh

Judy Loh gained a MSc in Biological Sciences from the University of Auckland, in 1999. She joined the Department of Ophthalmology in 2000. Her research focus is to add to the understanding of molecular mechanisms of corneal dystrophies, especially in keratoconus. Her skill set includes histology, immunochemistry and proteomics. She is an outstanding cell and tissue imager, utilising a variety of microscope and camera platforms.

Judy’s work is this area has resulted in 5 publications in peer reviewed journals, a book chapter and an imaging award.

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Immunolabelling of an extreme Descemet’s membrane rupture as a result of keratoconus with type IV collagen (red)