Allergen

Role

Our core expertise is in clinical aerobiology. Our role has three parts; the collection of different materials of biological origin that people inhale; secondly, the detection of different organisms and molecules within these samples, and thirdly, their relationship to respiratory diseases. These interests are being applied to outdoor and indoor allergen sources, bacterial products and viruses.

Research

Fungi and Halogen
We pioneered and continue to develop the Halogen assay. This is a method of immunostaining many types of particles (using IgE or monoclonal antibodies) from which allergens can be extracted. This year, the method was further extended to incorporate both Scanning Electron Microscopy (in collaboration with a Norwegian OH&S expert, Wijnand Eduard) and confocal microscopy (with Centres for Disease Control & Prevention in the USA).
It is currently used in collaboration with researchers in USA and UK.

The other area of fungal research completed this year was to examine illegally smoked materials (chop-chop tobacco and marijuana) as sources of respirable fungi. This arose from the interest of the Woolcock Smoking Cessation Group. Both sources were found to be rich in fungi, particularly of species recognised to be of respiratory health concern.

Influenza
We received a 6-month influenza-pandemic funding grant to prototype nasal filters for viral prophylaxis. Eleven months later we are at a stage of finalising the prototypes prior to exploring small scale production. Essentially the aims have been fulfilled. Two projects were funded as spin-offs from this.

Masks as a means of sampling exhaled virus aerosols
We constructed specialised masks to collect virus aerosols (rhinovirus, parainfluenza and influenza) that were generated by coughing, talking and breathing, that could then be identified by PCR and culture. This is the first time that aerosol virus has been measured in this way and provides new tools for modelling virus transmission and sampling.

Hypercapnia and N95 masks
We have some preliminary data indicating that wearing high efficiency filtration masks (N95 in USA, P2 in Australia and New Zealand) may raise the carbon dioxide in the bloodstream in some people. This may be caused by the large space created between the mask and the face accumulating exhaled carbon dioxide.

Plane trees and inner city symptoms
We are engaged in a collaborative, longitudinal community study to determine the causes of nasal and eye symptoms among inner city residents. In this we are continuously monitoring both different particles in the outdoor air at two locations, and the pattern of symptoms of local residents. Plane trees are commonly accused of being responsible for symptoms, but this may be because they are more visible than other allergen sources such as grass pollens. Additionally the symptoms may be the product of exposure to airborne irritant fibres from these trees

Feathers
We are collaborating in a study where half of a large group of children who are mite allergic and have asthma, have been supplied with feather bedding to determine whether this improves their symptoms of asthma. Such bedding is thought to decrease allergen exposure. We are measuring this and also a bacterial product called endotoxin that may also modulate symptoms. In some laboratory experiments we have also noticed that feather bedding may produce a huge number of fine feather fragments as well.

Skin
We are developing a novel hypothesis that exposure to airborne skin particles may have biological significance including stimulation of protection from allergies. At present it is recognised that exposure to kids, cows and cats early in life (among many other examples) are all associated with less allergy in later years. The conventional explanation is that these are associated with more microbial exposure in one form or another. However they also involve more exposure to skin flakes, and rather than being inert, these flakes carry a number of interesting glycolipids, proteins and other molecules that might regulate immunity, including allergy.

Fungal allergen
We have demonstrated that fungi are commonly inhaled by humans, and importantly that these fungi can exist in the nose in a living and germinating state - a factor which has previously been demonstrated to increase their release of allergenic proteins. This is basic research, further demonstrating the importance of fungi as aeroallergens. Results published in Aerobiologia.

Seasonal mite allergen trends
In collaboration with the Epidemiology Group, we are engaged in modelling the wealth of mite allergen data acquired over seven years in the study of childhood asthma (CAPS). At present we are looking at the seasonal patterns of humidity and temperature inside and outside houses and the concentrations of mite allergen in the beds of children over this time. Future work will include a time series analysis of these mite allergen concentrations with outcomes of sensitisation, asthma symptoms and emergency department admissions.