Developing new methods to identify airborne proteins responsible for causing allergic asthma
File(s)
Author(s)
Brian, Mary
Type
Thesis
Abstract
Allergic diseases such as asthma and hayfever are the most common chronic disease in
European children and adults and occur in response to substances present in the
environment, referred to as allergens. Allergens are present in indoor, outdoor and
occupational environments. In most cases, the allergen responsible for allergic symptoms
will be identified using diagnostic assessments such as skin prick testing; however, there are
examples of individuals experiencing allergic symptoms where the allergen responsible has
not yet been identified. This is particularly common in the occupational environment.
In this PhD I aimed to explore methods used to identify proteins highly likely to be allergens
and responsible for causing allergic asthma. I conducted a systematic review on asthma
outbreaks to describe which laboratory methods have been used to identify airborne
allergens. I then developed and optimised my own laboratory methods to identify airborne
proteins that could be responsible for causing allergic asthma.
I found that air sampling, skin prick testing and detection of serum specific-IgE binding were
the most frequent methods used to identify allergens associated with outbreaks of asthma.
Using known allergens from mouse urine, I developed and optimised a method to identify
unknown allergens. The method consists of an enhanced chemiluminescence western blot
and in-gel excision of serum specific-IgE binding regions, for protein identification by nano
liquid chromatography coupled to tandem mass spectrometry. Application of this method
identified potentially novel allergenic proteins existing within different occupational
settings. In animal testing facilities located in London and Salzburg, allergenic proteins were
identified from mouse urine, mouse epithelium and the common fruit fly (Drosophila
melanogaster). In supermarket scratch bakeries based in the UK allergenic proteins were
identified from ‘improver’ enzymes. I also developed methods for detecting outdoor
airborne protein from Teflon and polycarbonate filters used for air sampling.
The registration of allergens on online databases relies on researcher-based identifications
and the increase in allergen component-resolved diagnosis means this field is likely to
develop rapidly in the coming years. Further work is needed to confirm the allergenicity of
the proteins identified in this thesis, that may be responsible for causing allergic asthma.
European children and adults and occur in response to substances present in the
environment, referred to as allergens. Allergens are present in indoor, outdoor and
occupational environments. In most cases, the allergen responsible for allergic symptoms
will be identified using diagnostic assessments such as skin prick testing; however, there are
examples of individuals experiencing allergic symptoms where the allergen responsible has
not yet been identified. This is particularly common in the occupational environment.
In this PhD I aimed to explore methods used to identify proteins highly likely to be allergens
and responsible for causing allergic asthma. I conducted a systematic review on asthma
outbreaks to describe which laboratory methods have been used to identify airborne
allergens. I then developed and optimised my own laboratory methods to identify airborne
proteins that could be responsible for causing allergic asthma.
I found that air sampling, skin prick testing and detection of serum specific-IgE binding were
the most frequent methods used to identify allergens associated with outbreaks of asthma.
Using known allergens from mouse urine, I developed and optimised a method to identify
unknown allergens. The method consists of an enhanced chemiluminescence western blot
and in-gel excision of serum specific-IgE binding regions, for protein identification by nano
liquid chromatography coupled to tandem mass spectrometry. Application of this method
identified potentially novel allergenic proteins existing within different occupational
settings. In animal testing facilities located in London and Salzburg, allergenic proteins were
identified from mouse urine, mouse epithelium and the common fruit fly (Drosophila
melanogaster). In supermarket scratch bakeries based in the UK allergenic proteins were
identified from ‘improver’ enzymes. I also developed methods for detecting outdoor
airborne protein from Teflon and polycarbonate filters used for air sampling.
The registration of allergens on online databases relies on researcher-based identifications
and the increase in allergen component-resolved diagnosis means this field is likely to
develop rapidly in the coming years. Further work is needed to confirm the allergenicity of
the proteins identified in this thesis, that may be responsible for causing allergic asthma.
Version
Open Access
Date Issued
2019-03
Date Awarded
2019-08
Copyright Statement
Creative Commons Attribution NonCommercial Licence
Advisor
Jarvis, Debbie
Burney, Peter
Jones, Meinir
Sponsor
Medical Research Council (Great Britain)
National Heart and Lung Institute
Publisher Department
National Heart & Lung Institute
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)