Hyperpolarized Xenon-129 production system for magnetic resonance imaging of the lung

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Lung diseases, including chronic obstructive pulmonary disease (COPD), asthma and acute lung injury (ALI), are the fourth leading cause of death of Canadians and are expected to result in a third of all deaths by 2020, placing an enormous societal and economic burden on Canadians. There is a critical need to develop new lung imaging methods to provide: (i) earlier detection, (ii) fundamental insight into disease mechanisms and (iii) novel measures of therapeutic response to aid drug development. Magnetic Resonance (MR) imaging of specially-prepared (i.e. hyperpolarized) and inhaled inert gases, specifically helium-3 and xenon-129, offers an exciting new approach to elucidate the lung by providing an increase in signal of up to a factor of 100,000. This has revolutionized lung imaging by providing a highly sensitive and non-invasive method to obtain new regional indicators of lung disease. Unfortunately, helium-3 is an exceedingly rare isotope of helium and a recent global shortfall in helium-3 gas motivates the need for the equipment requested in this proposal. With this new equipment, we anticipate transitioning our research program away from helium-3 toward xenon-129 in the coming year. Xenon-129 can be hyperpolarized similarly to helium-3, is virtually limitless in its abundance in the atmosphere and can be procured at a fraction of the cost. It is widely foreseen that xenon-129 will be the pathway for this powerful lung imaging method in the future, particularly for wide-spread clinical application. This proposal requests funding to purchase the necessary equipment comprising a custom-built xenon-129 hyperpolarization system capable of meeting the needs of our on-going NSERC and CIHR-funded research program. Specifically, this request includes: (i) 150 W frequency-narrowed diode laser, (ii) custom glass-cell and thermal management system, (iii) associated sensors and control equipment and (iv) custom-built permanent magnet. The equipment will be assembled and tested in animals for the production of both sufficient quality and quantity of hyperpolarized gas to ensure a smooth transition of our lung imaging research program to xenon-129 by the end of Year 1.