Investigation Of The Association Between Chlamydial Infection And Asthma In Different Age Groups
Funder
National Health and Medical Research Council
Funding Amount
$382,117.00
Summary
Asthma is a common and severe lung disease that results from inflammation due to allergy and has symptoms of breathing difficulties, wheezing, chest tightness, and cough. Asthma is clinically characterised by the presence of certain types of responses from the immune system. We are looking for ways of preventing and curing asthma. There is a well known link between certain types of bacteria, called Chlamydia, and asthma but it is not known whether people develop asthma first and then get chlamyd ....Asthma is a common and severe lung disease that results from inflammation due to allergy and has symptoms of breathing difficulties, wheezing, chest tightness, and cough. Asthma is clinically characterised by the presence of certain types of responses from the immune system. We are looking for ways of preventing and curing asthma. There is a well known link between certain types of bacteria, called Chlamydia, and asthma but it is not known whether people develop asthma first and then get chlamydial infection or are infected first and this leads to asthma. We have shown that if adult mice are exposed to an allergen during chlamydial infection then the asthma gets worse. However, if newborn mice have a chlamydial infection then asthma is prevented when they are adults. These are preliminary observations, which we need to expand and understand the immune mechanisms that result in infection and allergy so that we can target them with antibiotics or vaccines. We will investigate how the timing of chlamydial infection relative to exposure to allergens (before, during or after) affects the development of asthma in adult mice. Newborns and young children have different immune systems to adults, so we will investigate what effects the infection of young mice has on infection and allergy later in life. We will also test a new vaccine we have developed against chlamydial infection to see if it can prevent chlamydial infection and infection-induced asthma. We will then examine if there is the same association between chlamydial infection and asthma in human asthmatics that present to hospital with exacerbation of their asthma. This work will help us develop new strategies for preventing and curing asthma, which may vary in different age groups. We will identify whether prevention of chlamydial infection by vaccination (or antibiotics) can be used to prevent and treat asthma.Read moreRead less
Exploration Of Exposures Associated With Bedding That Are Risks For Childhood Allergy And Asthma Symptoms
Funder
National Health and Medical Research Council
Funding Amount
$263,500.00
Summary
Asthma prevalence in Australia has doubled in the last 20 years, with 1 in 4 children now affected. House dust mites are probably the single most important allergen associated with asthma. The prevalence of mite allergy is linked to exposure, and such allergy when combined with high exposure, is a potent risk factor for asthma exacerbations. The current international advice for managing mite-allergic asthma, strongly advocates the use of bedding encasings as the best way to reduce exposure. Howe ....Asthma prevalence in Australia has doubled in the last 20 years, with 1 in 4 children now affected. House dust mites are probably the single most important allergen associated with asthma. The prevalence of mite allergy is linked to exposure, and such allergy when combined with high exposure, is a potent risk factor for asthma exacerbations. The current international advice for managing mite-allergic asthma, strongly advocates the use of bedding encasings as the best way to reduce exposure. However, three recent major trials using encasings and a meta-analysis of earlier trials all fail to show a clinical benefit. One of the applicants (ET) recently showed, using expertise in measuring personal exposure, that these encasings, as used, fail to significantly reduce aeroallergen exposure. By contrast, 3 recent Australian studies, involving the applicants, AK, ALP and NG showed that feather bedding compared to synthetic bedding, was strongly protective for asthma - the opposite of public advice. The suggested mechanisms involve reduced exposure to mite allergens, or altered exposure to bacterial endotoxin, but persuasive experimental support is lacking. We also propose a novel hypothesis that feather exposure may induce allergic 'tolerance'. Currently there is a lack of certainty about valid approaches to prevent asthma, and the Global Initiative for Asthma has described the need to understand mechanisms and improve interventions as urgent. This project is an ideal opportunity to combine the expertise of the CIA (ET) in measuring airborne exposures (mite, endotoxin, proteins) with that of the others who have expertise in children's asthma, and who are already involved in two large clinical trails involving different bedding and allergen avoidance. Our measurements of these bedding exposures and their clinical outcomes will provide, for the first time, a quantitative basis to refine public health allergen-based interventions to prevent and manage asthma.Read moreRead less
Expression And Function Of Fatty Acid Binding Proteins In Asthmatic Airway Epithelium
Funder
National Health and Medical Research Council
Funding Amount
$226,500.00
Summary
Asthma is an inflammatory disease of the lungs that affects over 10% of all Australians. It ranges in severity from mild to life-threatening. Although a number of drugs are currently available for the treatment of asthma, there are many people whose asthma does not respond very well to treatment. We have recently identified a gene called aP2 that is important in the development of asthma. Drugs targeted against this gene may be very useful in the treatment of asthma. In this project, we aim to u ....Asthma is an inflammatory disease of the lungs that affects over 10% of all Australians. It ranges in severity from mild to life-threatening. Although a number of drugs are currently available for the treatment of asthma, there are many people whose asthma does not respond very well to treatment. We have recently identified a gene called aP2 that is important in the development of asthma. Drugs targeted against this gene may be very useful in the treatment of asthma. In this project, we aim to understand how aP2 is turned on during asthma, and how it contributes to disease development. This information will be essential for designing optimal strategies for drug targeting of the aP2 pathway in asthma.Read moreRead less
Functional Analysis Of The Ym2 Chitinase-like Lectin In Allergic Airways Disease
Funder
National Health and Medical Research Council
Funding Amount
$283,767.00
Summary
The prevalence of asthma is widespread and nationally affects over two million Australians. Consequently, one of the Country s National Health Priorities is to improve our understanding of this condition. Analyses of the asthmatic lung reveal an airway wall that is thickened, an airway lumen that is obstructed and abnormal spasmogenicity of the airway smooth muscle: processes that collectively contribute to both acute and chronic respiratory dysfunction. Asthmatics develop an immune response tha ....The prevalence of asthma is widespread and nationally affects over two million Australians. Consequently, one of the Country s National Health Priorities is to improve our understanding of this condition. Analyses of the asthmatic lung reveal an airway wall that is thickened, an airway lumen that is obstructed and abnormal spasmogenicity of the airway smooth muscle: processes that collectively contribute to both acute and chronic respiratory dysfunction. Asthmatics develop an immune response that is biased toward production of allergy-related T helper 2 cytokines of which interleukin (IL)-13 is a potent mediator of disease. However, the molecular processes linking IL-13 with abnormal airway wall changes are unclear. To identify previously uncharacterised IL-13-related molecules, we used a protein profiling approach that identified a novel lectin (carbohydrate-binding protein) termed Ym2, which is secreted abundantly into the airway fluid of mice in which allergic airways disease has been induced. Preliminary studies suggest that Ym2 is an intermediary of IL-13 that is involved in respiratory dysfunction. This project aims to work out how Ym2 interacts with the molecules and cells of the respiratory tract to regulate allergic disease. Specific inhibitors of Ym2 will be developed to examine what happens to allergic responses when Ym2 can t function; transgenic mice will be developed to determine if we see features of allergy when Ym2 is over-expressed in the normal lung, and human samples will be screened to identify the human counterpart of Ym2 and whether this counterpart is secreted into the lung fluid of asthmatics. Defining the mechanism by which Ym2 regulates the pathogenesis of allergic disease will not only contribute to our basic understanding of the processes underlying asthma pathology, but also generate new information for better design of therapeutics directed against specific mediators of this debilitating and widespread disease.Read moreRead less
Immunomodulatory Effects Of Omega-3 Polyunsaturated Fatty Acids : Role In Allergy Prevention In Infancy
Funder
National Health and Medical Research Council
Funding Amount
$537,600.00
Summary
The dramatic increase in asthma and allergic disease over the last 20-30 years has highlighted the urgent need to identify associated environmental changes that may also be logical targets for disease prevention. Although this is likely to be multifactorial, one significant change during this period has been a progressive decline in the intake of dietary anti-inflammatory n-3 polyunsaturated fats (PUFA) in Western diets, with a corresponding increase in n-6 PUFA fatty acids. We recently showed f ....The dramatic increase in asthma and allergic disease over the last 20-30 years has highlighted the urgent need to identify associated environmental changes that may also be logical targets for disease prevention. Although this is likely to be multifactorial, one significant change during this period has been a progressive decline in the intake of dietary anti-inflammatory n-3 polyunsaturated fats (PUFA) in Western diets, with a corresponding increase in n-6 PUFA fatty acids. We recently showed for the first time that n-3 PUFA may have more significant effects in very early life before immune responses are fully established. We confirmed that maternal fish oil supplementation (n-40) resulted in significantly higher n-3 PUFA levels in newborns (compared to those with no supplements, n-43), and this was related to reduced immune responses to allergens (such as house dust mite, cat and egg). These observations suggest that n-3 PUFA can modify early immune development. Although this previous study was designed to assess immune outcomes (rather than clinical outcomes) we collected preliminary clinical data for the purposes of this application. We observed a consistent trend for less allergic symptoms and sensitisation in the supplementation group. These observations clearly warrant this proposed study to confirm these clinical effects, and to assess the mechanisms of action in considerably more detail. In this proposed study we will compare the effects of fish oil (n-165) or placebo (n-165) in early infancy (from 0-6 months of age). This much larger population will allow us to determine if increasing dietary n-3 PUFA is a way of reducing the chance of allergy in families where there is a high genetic risk. Approximately 40% of infants in Australia will go on to develop asthma or allergies. Strategies such as this that reduce the risk (even slightly) or the severity of disease expression could have enormous impact in this global context at relatively little cost.Read moreRead less