Allergic asthma is a severe respiratory syndrome affecting at least 300 million people worldwide. The syndrome arises after an erratic response of the immune system after inhalation of various allergens including pollen, spores, dust mites and animal dander. Whilst current treatments manage asthma symptoms, they are not a cure. Despite an urgent need to redefine clinical management of asthma, the base mechanistic science of the syndrome is still not fully understood. Recent striking work discovered a certain class of memory cell became long lived in the lung for months after allergen exposure, and whilst generally protective toward unrelated infections, these memory cells worsened asthma severity. Virtually nothing is known about the emergence of these cells in asthma, and this knowledge gap forms the core aim of this proposal to unravel the mechanisms by which these cells form, become dormant, and propagate disease. By integrating multiple state-of-the-art technologies and methodologies, I anticipate the pulmonary retention and activity of these cells will be determined by key protein/cell communication pathways important in allergic responses. Understanding these pathways is crucial if clinical management of severe asthma is to shift from focussing on the syndrome toward patient-tailored treatment regimens. This work will redefine current paradigms in allergic asthma progression and potentially propel novel avenues in therapeutic and clinical management of the syndrome.