House Dust Mites, Endosymbiotic Bacteria And Asthma
Funder
National Health and Medical Research Council
Funding Amount
$208,372.00
Summary
Asthma is a very common, chronic disease in both children and adults, with a prevalence of at least 5% worldwide. It continues to have a highly significant clinical and socio-economic impact on Western communities, despite the introduction of a variety of pharmacological treatments and there is evidence to indicate that the mortality rate from the disease is increasing. Several sources are known to be associated with asthma but the most frequently associated allergen is the house dust mite (HDM) ....Asthma is a very common, chronic disease in both children and adults, with a prevalence of at least 5% worldwide. It continues to have a highly significant clinical and socio-economic impact on Western communities, despite the introduction of a variety of pharmacological treatments and there is evidence to indicate that the mortality rate from the disease is increasing. Several sources are known to be associated with asthma but the most frequently associated allergen is the house dust mite (HDM) and allergy to it has been shown to be an independent risk factor. Our laboratory has been involved in these studies and have isolated several enzymes associated with digestion. We have also shown that the mite proteases are potent inducers of cytokines from respiratory epithelium, indicating that the biochemistry of allergens may be important in the sensitisation. During these studies, we have shown that mites produce enzymes which lysed Gram-positive bacteria. Analysis of one of these enzymes has revealed that mites are colonised by bacteria in their gut. These bacteria may well be a source of some of the allergens which provoke symptoms in asthmatic patients. In this grant proposal, experiments will be performed to assess this possibility. Such findings may have significant impact on our understanding of mite allergy as well as highlighting potentially new insights into mite control.Read moreRead less
Initiating Events In The Development Of Allergic Airway Inflammation
Funder
National Health and Medical Research Council
Funding Amount
$452,545.00
Summary
Despite recent advances we still do not understand the basic mechanisms which underlie the development of allergic airway inflammatory diseases such as rhinitis and asthma. It has been previously shown that when pollen are exposed to water they release a large number of very small starch granules which contain a number of potent allergens as well as plant steroids. In addition house dust mite allergens which are strongly associated with asthma are mostly located in small faecal pellets. Both the ....Despite recent advances we still do not understand the basic mechanisms which underlie the development of allergic airway inflammatory diseases such as rhinitis and asthma. It has been previously shown that when pollen are exposed to water they release a large number of very small starch granules which contain a number of potent allergens as well as plant steroids. In addition house dust mite allergens which are strongly associated with asthma are mostly located in small faecal pellets. Both these particles are ideally sized to enter the respiratory tract and initiate inflammatory responses. We have shown that these responses appear to be of the type that is needed to initiate allergic reactions. We intend to further study the interactions of these small inhaled allergen containing particles with cells of the respiratory tract. In this proposal we will look at both alveolar macrophages and respiratory epithelial cells. These approaches will not only provide new information about the processes of airway inflammation caused by allergens but may also define new therapeutic approaches to the treatment of these diseases.Read moreRead less