Professor Pettit is Mater Research’s Director of Biomedical Research and is a University of Queensland Amplify Fellow leading the Bone and Immunology Research Group. She has led basic biological discoveries in immunology, rheumatology, osteoimmunology and haematology resulting in increased understanding of myeloid cell contributions to priming immune responses, inflammatory arthritis, bone regeneration, bone diseases, and haematopoietic stem cell transplantation. Specific knowledge contributions led by Professor Pettit include: 1) first demonstration of RelB as a master transcriptional regulator of dendritic cell antigen presentation; 2) demonstration of RANKL as the essential rate limiting cytokine triggering pathologic bone resorption in inflammatory arthritis; 3) discovery of osteal tissue macrophages and characterization of their bone anabolic and catabolic support roles; 4) first demonstration that bone marrow resident macrophages influence haematopoieitc stem cell niche homeostasis and recovery from injury.