Using molecular genetics to understand grass species pollen deposition: enhancing bio-aerosol models and implications for human health.

Summary
In this proposal, we aim to revolutionise the way that pollen is measured, model the spatial and temporal deposition of different species of grass pollen and identify linkages to human health.
In the UK population ~5% suffer from allergic reactions (ranging from hay fever to asthma attacks) and further 22% are sensitised to grass pollen (i.e. they have antibodies capable of causing reactions). Grass pollen is the single most important outdoor aeroallergen closely followed by tree pollen. Similar to tree pollen, sensitivity towards grass pollen varies between species. However, we have no way of detecting, modelling or forecasting the aerial-dispersion of pollen from different species of grass. These limitations are due to complete lack of detailed source maps reflecting both the presence and abundance of different species of grass and because grass pollen, contrary to tree pollen, can not be separated into species using traditional observational methods. Therefore, combinations of the approximately 150 different species of grass pollen that are monitored (using approaches that remain unchanged since World War II) are lumped into a single category and form the foundation of the pollen forecast. In this project we will both develop new models and new methods of detection that address these major shortcomings.
The present situation means that hay fever suffers and health practitioners do not know what species, or combination of species cause present symptoms. Individuals can be tested for against particular grass species, but there are ca. 16 million people sensitised to grass pollen, allergic reactions are complex and testing the population against 150 different grass species species is an overwhelming task. The alternative is to take an environmental approach by developing exposure models and identify the environmental conditions that induce the allergic response, which then can be profiled to human health.
Recent developments in the generation of a UK plant DNA "barcode" library and DNA sequencing technologies have provided a unique and timely opportunity to identify the species, or combinations of species of grass that are associated with the allergic response. The important development of the UK plant DNA barcode library now gives us the ability to not only target individual species in molecular genetic analyses, but also assign identities to sequences derived from very high throughput molecular meta-analyses of complex mixtures of pollen grains. Similarly, recent developments in next generation air quality models and the advancement of computing power, has enabled the extension of these models into aerobiology in order to study the release, dispersion and transformation of bioaerosols and how this affects the environment.
Here, a group of multidisciplinary researchers specialising in aerobiological modelling, DNA barcoding/molecular genetic identification and environmental health have teamed up with the UK Met Office in order to (a.) develop a novel and high-throughput molecular genetic way of measuring the geographical spread and abundance of different allergenic species of grass across the summer months, (b.) develop novel pollen bio-aerosol models and (c.) identify which species, or combinations of species are linked to the most severe public health outcomes of the allergic response (i.e. asthma).
The work will provide information that healthcare professionals and charities will be able to translate into helping individuals live healthier and more productive lives. The information will help those with long term health conditions effectively self-manage their conditions, contribute more effectively to the workplace and be less reliant on the health system with accompanied economic benefits. Employers will benefit from greater employer productivity and pharmaceutical companies will be able to better target the distribution of their products and therapies.

General Public
Atopic respiratory diseases are highly prevalent in the UK population (approximately 10%). With potential treatment expensive and burden on the public health infrastructure high, avoidance of exposure to allergens is a key strategy in the prevention of allergy and asthma attacks. More accurate forecasts at species level will be possible with the technology developed in this project, and will provide information that will help individuals to find strategies to aid decreased exacerbation of current disease and help them live healthier, more productive lives. As the prevalence of allergy and asthma is high, even quite small gains from avoidance of allergen will result in large financial gains from reduced work absence and health care costs.
Health Care Professionals
The movement towards a stratified medicine paradigm as a key global priority for healthcare providers will see more individuals knowing more about the environmental factors that put them at risk of disease. Greater knowledge of individual risk factors (such as which species of plant an individual is allergic) will require greater granularity in exposure data, leading to better health outcomes. Capacity planners for A&E and clinical commissioning groups will value forecasting of patient flows to primary and secondary care.
Commercial/Private Sector
Pharmaceutical companies would also have an interest in forecasts of grass pollen maps to enable better distribution of their products, as well as tailoring immunotherapy products to match allergy rather than sensitisation in individuals. The Met Office (co-investigators on the grant) are already involved in the commercial sale of information relating to pollen, with interactions with pharmaceutical manufacturers and media outlets for dissemination of information.
Loss of productivity through absence from work is a major cost of UK employers and this can be reduced by better forecasting of environmental allergens. Information derived from this project will include which grass species are the major contributor to asthma exacerbations, which can be targeted for novel immunotherapy treatment. It will also provide information on which geographical areas are most at risk as well as which populations' in the community best would benefit from intervention (i.e. geographically, ethnically, age and sex).
Charities
We have been in communication with a variety of disease charities such as Asthma UK, Allergy UK and the British Lung Foundation. All have expressed interest in the project as they see their stakeholders (sufferers of asthma, allergies and Chronic Obstructive Pulmonary Disease, COPD) potentially being better able to manage their disease if they were forewarned of potential high risk exposure periods such that they could ensure correct medications were in their possession, alter behaviour (e.g. exercise routines, planning trips) and how best to reduce exposure to known allergens, with these realised in a short period of time.
Policy Makers and Government
Governments are closely monitoring land use changes. Construction of plant and pollen maps will allow this to be monitored at a finer degree of granularity leading to better predictions of outcomes from change. The ability for the NHS to predict spikes in Emergency Room visits via a pollen-asthma predictive tool will allow better management of a resource under considerable stress. This will also have repercussions for GP waiting lists. Improvements in the identification of allergenic species could be used in wider applications such as to inform councils with regards to vegetation planting schemes in parks and schools. Food production and food security professionals will be impacted by data and mapping collected on phenology and associated climate/weather predictions of pollen yields in the grasses and wider plant community in terms of prediction of plant and food production.