Professor James Thaventhiran in an academic clinical immunologist with clinical expertise in primary and secondary immunodeficiency Immunodeficienct patients are stratified by their vaccine responses and his research programme uses the vaccine response as an investigatory immune challenge for people. His research dovetails with his clinical practise with many reports directly relating to patients he has clinically managed. Hisresearch within genetics has described the novel diseases SOCS1, PTPN2 and IL6R deficiencies, moreover it has directly affected clinical management, leading to patients receiving experimental therapy and being offered potentially curative bone-marrow transplantation. Most recently he has explored the immune dysregulation in people with obesity and described the loss of a durable COVID-19 vaccine response in this demographic. His laboratory uses a combination of preclinical models and genetic loss of function studies in people to determine the physiological role of immune pathways in health. The personalisation potential of modified mRNA therapy offers the development of new therapies for patients with rare disease. Despite close to a billion people being treated with modified mRNA, much is still unknown about this revolutionary and novel therapeutic platform. His talk will present his lab’s past and ongoing work towards improving our design and use of modified mRNA.