Development Of A Novel Bioengineered Tissue Construct For Repairing The Eye.
Funder
National Health and Medical Research Council
Funding Amount
$335,817.00
Summary
Corneal diseases are often treated using donor tissue transplants. Nevertheless, donor tissue is unsuitable for treating the peripheral or limbal margin of the cornea. We have therefore developed a way to transplant sheets of limbal tissue (epithelium) grown in the laboratory from a patient's own cells, but this tissue lacks a foundation of connective tissue that we believe is essential for sustained healing. Thus, our aim is to develop a novel limbal transplant which contains both layers.
Optical And Neural Limits Of Visual Performance In Myopia
Funder
National Health and Medical Research Council
Funding Amount
$191,902.00
Summary
Short-sightedness (myopia) is one of our most common eye problems, affecting approximately 20% of people. It is usually due to the eye becoming too long for its power. While we can correct short-sight with contact lenses, spectacles and more recently refractive surgery, recent evidence shows that the vision of corrected myopes is poorer than that of people who have good distance vision without the need for an optical correction. This reduction is present even when the optical minification of spe ....Short-sightedness (myopia) is one of our most common eye problems, affecting approximately 20% of people. It is usually due to the eye becoming too long for its power. While we can correct short-sight with contact lenses, spectacles and more recently refractive surgery, recent evidence shows that the vision of corrected myopes is poorer than that of people who have good distance vision without the need for an optical correction. This reduction is present even when the optical minification of spectacle lenses is taken into account (the lenses used to correct short-sightedness make objects look smaller). It is possible that the anatomical changes to the eye that occur in short-sightedness are the cause of the reduced vision. Even if the optics can be fully corrected with refractive surgery, as is now being proposed, this may not result in excellent vision. The anatomical changes may occur in different parts of the eye and depending on where they occur the nature of the visual reduction will vary. The location of the retinal changes may also be important in terms of eventual pharmacological treatments for short-sightedness. In addition, the significance of the visual reduction, in terms of its effect on the functioning of short-sighted people, e.g. ability to perform under less than optimal visual conditions such as in the presence of glare or reduced light levels, is not known. We plan to investigate this by identifying the optical and neural contributions to visual performance in short-sighted people.Read moreRead less
The Role Of Collagenase (MMP-1) In The Pathogenesis Of Human Pterygia
Funder
National Health and Medical Research Council
Funding Amount
$246,100.00
Summary
Pterygia are a common, recurrent, disfiguring, and sight-threatening disease of the human eye. This disease is extremely common world wide and particularly in the Australian aboriginal population. The triggers for this disease are unknown. Prolonged exposure to environmental elements, such as ultra violet (UV) light, is proposed to be the main initiating factor. Our previous studies have shown the important role played by a family of proteolytic enzymes (metalloproteinases) in the progressive an ....Pterygia are a common, recurrent, disfiguring, and sight-threatening disease of the human eye. This disease is extremely common world wide and particularly in the Australian aboriginal population. The triggers for this disease are unknown. Prolonged exposure to environmental elements, such as ultra violet (UV) light, is proposed to be the main initiating factor. Our previous studies have shown the important role played by a family of proteolytic enzymes (metalloproteinases) in the progressive and invasive nature of pterygia. We have significant preliminary evidence that a large percentage of patients with pterygia carry a mutation in one of these enzymes (collagenase-1). This is the most abundant enzyme expressed in pterygium tissue and probably plays a major role in invasion and progression in this disease. UV light activates cells in pterygia to induce expression of collagenase-1. This study will determine whether or not people with a genetic predisposition are more likely to develop pterygia and whether or not environmental factors, such as UV light, trigger progression of disease. If this is the case, then subjects with this genetic predisposition would be at increased risk for the development of pterygia (and their complications) and could be advised to take preventative measures to minimize the risk of developing this disease.Read moreRead less
Studies Of Antigen Presenting Cells In The Anterior Segment Of The Eye And Their Role In Immune-mediated Ocular Disease
Funder
National Health and Medical Research Council
Funding Amount
$241,018.00
Summary
Dendritic cells (DC) are considered the 'sentinels' of the immune system because they are capable of trapping antigenic material derived from invading organisms such as bacteria and viruses in peripheral tissues-organs (skin, gut, respiratory tract etc) and then transporting these antigens to the lymphoid organs where they 'alert' the immune system to potential 'dangers' and elicit appropriate T cell responses. If the antigens are novel this mechanism forms the basis of primary cell-mediated imm ....Dendritic cells (DC) are considered the 'sentinels' of the immune system because they are capable of trapping antigenic material derived from invading organisms such as bacteria and viruses in peripheral tissues-organs (skin, gut, respiratory tract etc) and then transporting these antigens to the lymphoid organs where they 'alert' the immune system to potential 'dangers' and elicit appropriate T cell responses. If the antigens are novel this mechanism forms the basis of primary cell-mediated immune responses. Previously 'educated' T cells may upon contact with antigens in the periphery (when presented by other antigen presenting cells [APCs], such as macrophages) become activated. This forms the basis for secondary immune responses. Immune and inflammatory responses in the eye are held in check to avoid permanent damage to the delicate tissues and maintain visual function. The mechanisms which regulate immunological responses in the eye are only now becoming clear. Studies in the Chief Investigators laboratory over the last 7 years have been aimed at unravelling the life cycle and function of APCs in the eye. The present study has three specific aims: 1) Determining whether DC in the eye once they have taken up antigens migrate to the spleen or local lymph nodes? 2) The second aim of this project is to use an animal model of uveitis and transfer fluorescent labelled donor T cells to study the events in the living eye which lead to autoimmune uveoretinitis. In particular we wish to identify the cells that present antigen to infiltrating lymphocytes. 3) Patients often develop posterior uveitis (an autoimmune condition) after a cold or bacterial infection. We aim to mimic conditions of acute inflammation in the eye to see whether this may secondarily predispose the eye to attack by autoreactive lymphocytes.Read moreRead less
Retinal Vascular Signs As Predictors Of Systemic Disease Outcomes: 10-year Evolution In A Population-based Cohort
Funder
National Health and Medical Research Council
Funding Amount
$389,575.00
Summary
Recent U.S. data from two population-based studies have highlighted retinal microvascular signs as being predictive of systemic vascular and other important health outcomes in middle-aged or older individuals, particularly stroke and heart attack and mortality, independent of traditional vascular risk factors. The present application proposes to evaluate the 10-year development and progression of retinal microvascular signs and their relations to the development of stroke and other important sys ....Recent U.S. data from two population-based studies have highlighted retinal microvascular signs as being predictive of systemic vascular and other important health outcomes in middle-aged or older individuals, particularly stroke and heart attack and mortality, independent of traditional vascular risk factors. The present application proposes to evaluate the 10-year development and progression of retinal microvascular signs and their relations to the development of stroke and other important systemic health outcomes in the population-based cohort of residents attending the Blue Mountains Eye Study (BMES. Two types of retinal signs will be evaluated: firstly, the presence of specific clinical signs, such as focal narrowing of small retinal vessels (arterioles), nicking of retinal veins as arterioles cross them or presence of retinopathy (haemorrhages and other signs) secondly, measures of generalized retinal vessel calibre (narrowing) using a computer-assisted method developed for the U.S. studies. We will also develop new grading methods for two other signs. Late and will compare computer-assisted grading from 35mm slides to automated grading of vessels using a scanning device (being developed) to screen the eyes of older persons. This project builds upon our current 3-year NHMRC grant (ID153948; 2001-2003) Retinal vascular signs as risk markers for incident stroke or cerebrovascular death: A population-based assessment . In the last 2 years, this has explored different aspects of measurement and grading of these signs, has documented their relation to blood pressure and has begun to assess whether these features predict vascular events and other systemic outcomes in older Australians. The new project will assess the evolution of retinal microvascular signs over a 10-year period, using data and retinal photographs from the 10-year examinations of the BMES cohort, currently being collected, in a further current NHMRC grant (ID211069; 2002-2004).Read moreRead less