Development and characterisation of multi-cellular lung organoids for use in Bovine TB research

Despite decades of research, Bovine Tuberculosis (BTb) continues to cause significant animal welfare and economic issues globally. Caused by the intracellular bacterium Mycobacterium bovis, this zoonotic pathogen also infects and causes disease in humans and multiple animal species. Current diagnostic tools, vaccination and treatment options are not ideal; resulting in a continued reliance on the 'test and cull' strategy in the UK.

In this project, we aim to optimise the production of multi-cellular bovine lung organoids derived from bovine stem cells, and/or abattoir material, with the ultimate goal of reducing the numbers of live animals used in BTb research. These 'lungs-in-a-dish' (Archer et al. 2021, doi: 10.1186/s13567-021-00946-6) will be extensively characterised by comparing their cellular composition with bovine lung tissue, using a variety of approaches such as immunohistochemistry and quantitative RT-PCR techniques. Once the conditions for optimal organoid production are established, this project will be extended to study the interaction of M. bovis strains obtained from diverse locations within the UK which differ in virulence cattle, and in their ability to survive and replicate in bovine macrophages (Jensen et al. 2018, doi: 10.1128/IAI.00385-17; Jensen et al. 2020, doi: 10.1371/journal.pone.0222437). Cellular responses and the survival of the bacterium over time will be studied. In addition the interaction of infected cells with mucosal innate immune cells, which will be provided in co-culture, will also be explored. The information deriving from these studies will be invaluable in the development of more specific and sensitive diagnostic tools for BTb and provide important insights into the immunobiology of the lung: M. bovis interaction required for the smart design of future vaccination strategies.