Is Lyn Tyrosine Kinase A Predictor Of Severe, Persistent Multi-trait Asthma And Allergy?
Funder
National Health and Medical Research Council
Funding Amount
$250,250.00
Summary
Asthma is a major health problem in Australia affecting over 10% of the population at any time, and more than 25% of the population at one stage in their lives. Although the public perception is that asthma treatments have improved management of the disease, more than 700 people die from severe asthma each year and hospitalisation from exacerbation (sudden worsening) is one of the most costly components of the health care burden in Australia and most developed countries. Currently there are no m ....Asthma is a major health problem in Australia affecting over 10% of the population at any time, and more than 25% of the population at one stage in their lives. Although the public perception is that asthma treatments have improved management of the disease, more than 700 people die from severe asthma each year and hospitalisation from exacerbation (sudden worsening) is one of the most costly components of the health care burden in Australia and most developed countries. Currently there are no molecular markers that can predict who will get severe asthma and there are no specific treatments to reverse severe exacerbations. This project will use advanced molecular biology methods to examine whether a molecule called Lyn may be important. The Lyn tyrosine kinase is a member of a family of genes that participate in transmitting information across the cell membrane. This enzyme is expressed in blood cells, and is involved in mechanisms pertaining to infection, immunity and allergic responses. To further our understanding of the role of this enzyme in the context of the whole animal, we have generated mice that are unable to make Lyn protein (Lyn-deficient mice). In animal models of asthma we know that if Lyn is not functioning, severe and persistent asthma develops. We have also made preliminary studies that suggest that Lyn does not work properly in people who have been admitted to the emergency ward with life threatenting asthma. In this study we will examine in detail the role that Lyn plays in asthma and allergy, and we intend to identify the pathways that give rise to asthma in Lyn-deficient mice. We will also investigate our hypothesis that Lyn activity may be reduced or disregulated in patients with asthma and allergy. This research should lead to better predictive markers for severe asthma and also to improved and specific treatments.Read moreRead less
Airway Inflammation In Asthma And Chronic Obstructive Pulmonary Disease
Funder
National Health and Medical Research Council
Funding Amount
$390,509.00
Summary
In chronic diseases of the airway such as asthma and airway narrowing due to cigarette smoking - chronic obstructive pulmonary disease (COPD), the airways show inflammation (increased numbers of cells and their products) and remodelling (increased thickness and scarring) which persist for many years, possibly indefinitely. The exact mechanisms by which inflammation persists in the airway wall in asthma and COPD are unknown. We and others have shown that greater numbers of memory T-lymphocytes (T ....In chronic diseases of the airway such as asthma and airway narrowing due to cigarette smoking - chronic obstructive pulmonary disease (COPD), the airways show inflammation (increased numbers of cells and their products) and remodelling (increased thickness and scarring) which persist for many years, possibly indefinitely. The exact mechanisms by which inflammation persists in the airway wall in asthma and COPD are unknown. We and others have shown that greater numbers of memory T-lymphocytes (T-cells) are present in the airway wall in asthma and COPD. T-cells orchestrate the processes involved in inflammation. We have hypothesised that the persistence of airway inflammation in asthma and COPD results from the proliferation of memory T-cells within the airway wall. Unlike na ve T-cells, memory T-cells have previously been stimulated and can easily be activated to proliferate and promote inflammation by other cells which are fixed in the airway. Data from our current work examining this process suggests that, although cells fixed in the airway such as fibroblasts and macrophages are activated in asthma and COPD and may activate T-cells, they do not seem to be causing T-cell proliferation. We now wish to extend these studies by determinimg if memory T- lymphocytes are proliferating in the airway wall within aggregations of lymphoid cells which act like lymph nodes and promote T-cell growth. To do this we will compare the number of these aggregations and the types of T-cells they contain in mild and severe cases of asthma and COPD with those in normal subjects. This work will provide new knowledge to help understand the mechanisms for the persistance of airway inflammation in asthma and COPD and may thereby also provide a focus for effective treatments of these condition.Read moreRead less