PROGRAMMING NATURAL KILLER CELL FUNCTION THROUGH ORGANELLE COMMUNICATION

Natural killer (NK) cells play a crucial role in responding to virus-infected or transformed cells. Their ability to kill target cells hinges on a process known as NK cell education, where they calibrate against self-MHC. Intriguingly, the strength of inhibitory signals during this education correlates with the NK cell's functional potential. Yet, how these inhibitory signals during education store functional potential remains unclear. Understanding this process is vital for developing NK-cell based therapies for infections, autoimmunity, and cancer. Our research has shown that inhibitory interactions in educated NK cells lead to an accumulation of dense-core secretory granules. This indicates a new concept in the functional regulation of NK cells. We aim to test the hypothesis that intracellular organelle communication is key to NK cell education. We've developed an imaging platform to study the biochemical pathways regulating the formation and fate of these granules in NK cells, and to explore their role as programmable signalling hubs in lymphocytes. Additionally, we've established a comprehensive single-cell RNA sequencing resource, identifying the regulatory gene network underpinning NK cell differentiation, especially in metabolism and cytotoxic functions. Using machine learning algorithms, particularly transfer learning, we've begun to unravel the dysregulation of NK cells in the tumor microenvironment. This research is poised to offer new insights into the biochemical and genetic pathways that adjust NK cells' intrinsic functional potential, paving the way for innovative cancer treatments based on modulating lymphocyte function.

Natural killer (NK) cells are key cellular components of the innate immune system and achieve specificity through unique combinations of germ-line encoded receptors. These receptors are critical for the calibration of functional potential in NK cells through a process termed education. NK cell education is conserved across different species and is essential for the maintenance of self-tolerance and the ability to recognise tumour and virally infected cells. However, the molecular mechanisms connecting homeostatic surface receptor signalling to an NK cell?s intrinsic functional potential have remained a key knowledge gap. We have recently shown that inhibitory interactions lead to an accumulation of dense-core secretory granules in educated NK cells. Our findings allow us to explore a fundamentally new concept concerning the functional regulation of NK cells through dynamic changes to the morphology of the acidic compartment. We propose an essential role for secretory granules acting as a signalling organelle in NK cells. We will use a combination of pioneering technologies, including single-cell transcriptional and functional analysis, imaging, subcellular proteomics, mass cytometry and small-molecule screening to: i) Delineate the genetic and biochemical pathways that regulate the formation and fate of dense-core secretory granules in NK cells. ii) Decipher the molecular basis for intracellular communication between organelles and its role in regulating functional potential in NK cells. iii) Explore the utility of the secretory granule as a programmable signalling hub in lymphocytes. Collectively, these complementary approaches will open a completely new research direction and shed light on the utility of the secretory granule as a programmable organelle. Our studies will provide critical information concerning the inner workings of NK cell education and pave the way for new treatments in cancer and autoimmunity based on modulation of lymphocyte function.