Defining the role of the HOst MIcrobiome in SPECialty patient populations (HOMISPEC)

Lead- PhD Candidate Dr Olivia Smibert

The microbiome refers to the population of organisms and their genetic material that inhabit the surface of the body, particularly the gut. There is increasing appreciation for the role that this population of organisms plays in influencing both health and disease states within the gastrointestinal tract and at more remote sites in the body. This includes infectious diarrhea and inflammatory bowel disease, responsiveness to cancer chemotherapy and outcomes after organ transplant amongst others. Our understanding of the microbiome is largely based on descriptions of the bacterial populations with far less known about the other organisms, which include viruses and fungi, that make up the broader microbial ecosystem.   

Homispec is evaluating whether the microbiome of hematology patients receiving specialized therapy including chemotherapy, cellular immune-based therapy (such as CAR-T or bispecific T-cell engager therapy) and those that proceed to stem cell transplant and liver transplant recipients can be used to identify patients at risk of subsequent infectious and adverse transplant-related outcomes.  Patients are being enrolled at Austin Health, Royal Melbourne Hospital and Peter MacCallum Cancer Centre. Participants provide saliva samples, stool and peripheral blood samples on an intermittent but regular basis during the study period. Participant sampling is focused at times of hospitalization but participants are also be asked to provide regular, but less frequent samples while an outpatient. For outpatient samples participants are provided with home saliva, stool collection kits that they can return to the hospital at subsequent appointments to provide blood samples.  Healthy and hospitalised control participants are invited to provide samples at a single time point only. Saliva, stool and plasma samples is being stored and will undergo microbiome and metabolomics analyses with collaborators at the Peter Doherty Institute and will link the activity of microbiome with the systemic immune response with patient outcomes.