Professor Hayday trained as a biochemist, undertook PhD studies in tumour virology, and then pursued post-doctoral training at MIT where he characterised chromosome translocation breakpoints in human B cell lymphomas, and contributed to the identification of the hitherto unanticipated gamma delta T cell compartment by being the first to describe the T cell receptor gamma chain genes.
In 13 years on the Faculty at Yale, he helped show that gamma delta T cells illustrate a distinct, unrecognised aspect of lymphocyte biology, including the cells’ disproportionate association with tissues rather than with lymphoid organs, and their rapid responses to tissue-“stress”. At a time when tumour immune surveillance was not widely accepted, his laboratory showed that mice lacking gamma delta T cells are profoundly more susceptible to carcinogens.
Professor Hayday now works at King’s College London, with a joint appointment at the Francis Crick Institute, where his research seeks to identify key molecular processes and mechanisms that regulate lymphoid stress surveillance, and to relate them to tissue inflammation and cancer. His research involves some international, long-term collaborations, and spans the development of the novel reductionist molecular models to the formulation of clinical trials.