Mast Cells - Bystanders Or Instigators Of Airway Remodelling In Asthma?
Funder
National Health and Medical Research Council
Funding Amount
$623,764.00
Summary
Current asthma treatments have little effect on changes to the breathing tubes in our lungs. The tubes are thickened and stiffer, with more muscle, blood vessels, matrix and mucus. We propose that a particular inflammatory cell, called a mast cell, causes these changes to the breathing tubes and we will find out how it does that. Thus this project will establish why and how the changes to the breathing tubes happen in asthma and reveal how best to target and reverse-prevent them in the future.
Distribution Of Monodisperse Aerosols Inhaled By Children For Determination Of Optimal Therapeutic Inhaler Formulations
Funder
National Health and Medical Research Council
Funding Amount
$326,000.00
Summary
Inhalers are the primary form of treatment for asthma, allowing the delivery of lower doses of medication directly to the lungs. Consistent daily use of these inhalers is often necessary to effectively control the symptoms of asthma. Inhalers are now increasingly used to treat infants with lung problems. Many of these inhalers are not designed for use by such young children, who may be unable to perform the breathing techniques necessary for effective use of these inhalers. Not all the drug inha ....Inhalers are the primary form of treatment for asthma, allowing the delivery of lower doses of medication directly to the lungs. Consistent daily use of these inhalers is often necessary to effectively control the symptoms of asthma. Inhalers are now increasingly used to treat infants with lung problems. Many of these inhalers are not designed for use by such young children, who may be unable to perform the breathing techniques necessary for effective use of these inhalers. Not all the drug inhaled by patients will end up in the lungs where it is needed; a large proportion is left in the mouth, throat and stomach. Our earlier studies have shown that there is a large amount of variability in the amount of drug received by children using inhalers. We intend to assess the important factors involved in improving the efficiency of inhaler therapy for children, such as the size of the inhaled particles and the breathing pattern of the child. The results obtained from this study will enable us to determine the best method of delivering these drugs to children so that they only receive the lowest effective dose for treatment of the symptoms of asthma while minimising unwanted effects.Read moreRead less
Self-limiting Anti-inflammatory Actions Of Glucocorticoids In Asthma
Funder
National Health and Medical Research Council
Funding Amount
$377,036.00
Summary
Asthma is a disease characterised by excessive narrowing of the airway tubes resulting in difficulty exhaling air from the lungs. Symptoms of asthma include coughing, wheezing, shortness of breath and difficulty in breathing. Asthma affects almost 1 in 5 Australians and is especially prevelant in children. One in every three Australians will suffer from symptoms of asthma at some time in their life and despite current therapy, asthma is responsible for the deaths of more than 700 Australians eve ....Asthma is a disease characterised by excessive narrowing of the airway tubes resulting in difficulty exhaling air from the lungs. Symptoms of asthma include coughing, wheezing, shortness of breath and difficulty in breathing. Asthma affects almost 1 in 5 Australians and is especially prevelant in children. One in every three Australians will suffer from symptoms of asthma at some time in their life and despite current therapy, asthma is responsible for the deaths of more than 700 Australians every year. Airway tubes of asthmatics have more and larger contractile muscle cells lining the tubes. This increase in muscle mass results from chemicals that are released from white blood cells that migrate into the airway tubes during and after asthma attacks. This thickening slows airflow through the airway tubes because the muscle mass bulges into the holes of the tubes and when the muscle shortens the total diameter of the tubes decrease. We have recently shown that steroids used by asthmatics to treat the white blood cell contribution to the disease can reduce the growth of airway muscle. However, when the muscle has been pretreated with factors that are present in the inflamed airway, the anti-growth effects of steroids are prevented. This effect of the steroids is due to reduced production of a substance called prostaglandin E2 which can also reduce the growth of muscle. Thus, whilst steroids may help in treating some of the symptoms of asthma, they may be suboptimal in the treatment of muscle thickening and other aspects of the disease which involve cell division and multiplication. Our specific question in the next phase of this research is whether steroid inhibition of the release of prostaglandins compromises the useful actions of steroids on the growth of the airway tubes. The findings of this proposed study will provide new information on the role of steroids in asthma and may lead to better therapeutic strategies for the treatment of severe asthma.Read moreRead less
Intravascular Leukocyte Trafficking During Thromboinflammation
Funder
National Health and Medical Research Council
Funding Amount
$668,742.00
Summary
Unblocking blood vessels to treat heart attack and stroke can unfortunately cause a paradoxical worsening of organ damage, due to increased inflammation upon blood flow restoration. We have identified a novel way in which this side-effect is regulated by the small blood clotting cells platelets, and the protein fibrin. We will investigate ways to reduce the pro-inflammatory role for platelets, and define safer clot busting treatments.
While many cases of asthma are mild, severe cases require extensive health care resources and are virtually unresponsive to conventional treatment. This project will investigate whether specific compounds released from the airway are able to cause lung damage and airway abnormalities similar to that in severe asthma. We will investigate whether these changes are responsive to conventional therapy and investigate a potential treatment for regaining this responsiveness in severe asthma.
Mechanisms Of Airway Narrowing In Eosinophilic And Non-eosinophilic Asthma
Funder
National Health and Medical Research Council
Funding Amount
$500,593.00
Summary
Asthma is associated with excessive airway narrowing, increased thickness of the airway wall and inflammation, most typically with eosinophils. However, 50% of cases have few eosinophils and respond less well to current treatments. This project will examine differences in airway structure between patients with or without eosinophils, using post-mortem tissue, as part of an international research collaboration.
Mannitol In The Assessment Of Bronchial Responsiveness In Airway Disease
Funder
National Health and Medical Research Council
Funding Amount
$365,250.00
Summary
The airways of people with asthma respond by narrowing too easily and too much to a wide range of stimuli. The tests most commonly used to measure airway responsiveness in asthma are the pharmacological agents methacholine and histamine. When inhaled, they act directly on bronchial muscle causing it to contract and hence the airways to narrow. We have developed a non-pharmacological test using a dry powder of a sugar - mannitol. When inhaled, mannitol causes narrowing of the airways in asthmatic ....The airways of people with asthma respond by narrowing too easily and too much to a wide range of stimuli. The tests most commonly used to measure airway responsiveness in asthma are the pharmacological agents methacholine and histamine. When inhaled, they act directly on bronchial muscle causing it to contract and hence the airways to narrow. We have developed a non-pharmacological test using a dry powder of a sugar - mannitol. When inhaled, mannitol causes narrowing of the airways in asthmatics but little or no effect in healthy subjects. Many asthmatics respond to mannitol even when they have few symptoms of asthma. Mannitol causes the airways to narrow 'indirectly' by causing the release of substances from inflammatory cells in the airways (e.g. histamine, leukotrienes and prostaglandins) that cause the muscle to contract. After the inflammation has cleared, either by treatment with inhaled steroids or spontaneously, the response to mannitol is close to healthy subjects. Thus the response to mannitol depends on the presence of inflammation and loss of responsiveness means resolution of inflammation. The significance of this is that the mannitol test may be used as an 'inflammometer'. It would be important if airway responsiveness to mannitol could be used to identify individuals with airway diseases other than asthma, (chronic bronchitis, and chronic obstructive lung disease) who could benefit from treatment with inhaled steroids. This would be significant as there is currently no test to identify those individuals and there are unwanted effects from using steroids. Further, it may be possible to use mannitol to identify individuals with other inflammatory diseases who may be at risk of developing asthma. Some people with asthma, chronic bronchitis and chronic obstructive lung disease have increased levels of oxidative stress. We wish to identify those people and to measure change after treatment with steroids.Read moreRead less
Understanding And Preventing Airborne Transmission Of Infectious Respiratory Aerosols
Funder
National Health and Medical Research Council
Funding Amount
$393,894.00
Summary
This project aims to significantly advance our understanding of how infectious bacteria are transmitted through the air, and what basic control measures are most effective at preventing this. This research is focused on persons with cystic fibrosis (CF), as they may be particularly susceptible to such transmission, but our results will also help us better understand how other infections are spread through the air. This is especially important given the recent global influenza pandemic.