Stephen studied Immunology and Biochemisty at the University of Adelaide, graduating with first class honours in 2004. He continued his study in Adelaide, undertaking a PhD at the University of Adelaide and Hanson Institute. During this period he evaluated how tyrosine kinase inhibitors, an emerging therapy for chronic myeloid leukemia also can dampen host immune responses. In 2009 he moved to Brisbane to take up a University of Queensland Postdoctoral Fellowship at the Diamantina Institute. Here he worked to develop novel cancer therapies to enhance host immune responses against cancer cells. These included dual functional siRNA that could both inhibit oncogene expression in cancer cells and activate host immune responses through TLR7 signalling. He also evaluated the role of the T-cell checkpoint PD-1 in mediating T-cell tolerance and how blockade can enhance adoptive immunotherapy in tumor bearing mice. This interest in immunotherapy was continued as he moved to the QIMR-Berghofer institute in Brisbane. During this period his worked helped identify new members of the nectin interacting receptors as potential targets to enhance natural killer cell control of metastases. He was also involved in developing a pre-clinical model to test for toxicity and anti-tumor efficacy of novel immunotherapies before they are used in patients.

Stephen moved back to Adelaide in 2016 to join David Lynn’s group at SAHMRI in order to pursue a developing interest in the gut microbiota influence over host immune function, a key focus of his group which was recently demonstrated by a high impact paper in Cell Reports Medicine. Within Prof. Lynn’s group, he has jointly developed a research program to study how the microbiota can influence the efficacy, toxicity and patient recovery from immunotherapy and conventional cancer therapies.