Unraveling Mechanisms Of Liver Transplant Tolerance
Funder
National Health and Medical Research Council
Funding Amount
$694,822.00
Summary
Liver transplants are unique amongst solid organs as they are spontaneously accepted across different individuals and induce acceptance of other organs from the same donor co-transplanted at the same time. Using a new mouse liver transplantation model, this proposal will elucidate how the liver tissue performs this function and identify new markers associated with tolerance in the blood of mice. This knowledge will be used to identify liver transplant patients with reduced rejection risk.
Preconditioning: The Molecular Basis For Protection From Hepatic Ischemia-reperfusion Injury
Funder
National Health and Medical Research Council
Funding Amount
$406,980.00
Summary
When the blood supply to the liver is cut off temporarily (ischemia) and later restored (reperfusion) the liver is damaged by a process called ischemia-reperfusion (IR) injury. This is a major problem during liver surgery and is also an underlying problem in liver transplantation; following storage of a donor liver ready for placing into the recipient it can undergo a similar process called preservation injury. We now understand a lot about how IR comes about, particularly by the formation of da ....When the blood supply to the liver is cut off temporarily (ischemia) and later restored (reperfusion) the liver is damaged by a process called ischemia-reperfusion (IR) injury. This is a major problem during liver surgery and is also an underlying problem in liver transplantation; following storage of a donor liver ready for placing into the recipient it can undergo a similar process called preservation injury. We now understand a lot about how IR comes about, particularly by the formation of damaging oxygen radicals within liver cells to start a process of programmed cell death, but it remains difficult to prevent or treat IR injury. A recent breakthrough has been recognition that subjecting the liver to only a short period (5 or 10 minutes) of ischemia protects against a later period of prolonged ischemia or IR. In the investigator s mouse model, for example, such preconditioning was 60 to 90% protective (depending on the time after IR). This project seeks to understand how preconditioning works to protect the liver against IR injury. Our idea is that preconditioning generates a limited amount of oxygen radicals, and that these turn on signalling pathways in the cell that regulate certain protective genes. Genes that encode antioxidant and other anti-stress pathways are likely to be important, but so are genes that prepare the cell to enter the cell cycle and divide into new cells that regenerate the liver. Conversely, genes that program cell death may be turned off. The outcomes of this research will be to understand the molecular and cellular basis of how preconditioning protects against ischemia-reperfusion injury of the liver. This will allow drug treatments to be devised that, by simulating preconditioning, prevent this common and severe type of liver damage.Read moreRead less
Optimizing Implanted Cell Survival Using A Tissue Engineering Model
Funder
National Health and Medical Research Council
Funding Amount
$589,175.00
Summary
Cell therapy and tissue engineering involve the insertion of specific cells into damaged tissues or into a bioraector in a patient's body to generate new replacement tissues. This project seeks to improve two factors associated with inserting cells : 1. The innate survival characteristics of the cells being inserted, and 2. The blood vessel supply at the site of insertion. These techniques will greatly improve the survival of inserted cells.
Detection Of Liver And Renal Function Abnormalities In The Australian & New Zealand Population Of Fontan Patients
Funder
National Health and Medical Research Council
Funding Amount
$345,080.00
Summary
Children born with complex heart defects and only one pumping chamber can now live into adulthood with an operation called the Fontan procedure. As this operation has only existed for 40 years, the long-term expectations for these children and young adults are still unclear, and their population is growing every year. There is now evidence that they may suffer from liver and kidney failure. This project will identify the severity of liver and kidney damage in our population of Fontan patients.
Activin A And Follistatin Are Potential Key Regulators Of Organ Transplant Dysfunction And Graft Survival.
Funder
National Health and Medical Research Council
Funding Amount
$535,579.00
Summary
The grant examines novel key regulators in organ transplantation. It examines molecules that are released during transplant surgery and on the return of blood flow to the organ which can cause inflammation and scarring. The release is increased by heparin, an anticoagulant used in organ preparation. Alternative anticoagulants and blockers of the regulators released will be tested to prevent the damage to the transplant, potentially improving both the short and long term graft survival and functi ....The grant examines novel key regulators in organ transplantation. It examines molecules that are released during transplant surgery and on the return of blood flow to the organ which can cause inflammation and scarring. The release is increased by heparin, an anticoagulant used in organ preparation. Alternative anticoagulants and blockers of the regulators released will be tested to prevent the damage to the transplant, potentially improving both the short and long term graft survival and function.Read moreRead less
Enkephalin Metabolism In Cardiac Ischemia, Heart Failure And Cardiac Surgery
Funder
National Health and Medical Research Council
Funding Amount
$327,037.00
Summary
It has recently been discovered in animal studies that heart muscle can make its own opioid proteins. Previously, it was thought that only nerves made and released opioids. We have recently found that a class of opioids called enkephalins are made and then depleted from the heart during the stress of oxygen and nutrient deprivation. Enkephalins have been found to have potent metabolic effects on the heart. Previous work has shown that opioids can protect the heart against injury incurred during ....It has recently been discovered in animal studies that heart muscle can make its own opioid proteins. Previously, it was thought that only nerves made and released opioids. We have recently found that a class of opioids called enkephalins are made and then depleted from the heart during the stress of oxygen and nutrient deprivation. Enkephalins have been found to have potent metabolic effects on the heart. Previous work has shown that opioids can protect the heart against injury incurred during disease that restricts energy and oxygen supply to the blood vessels and heart. We wish to demonstrate this for the first time in human heart, and we will explore whether the production of enkephalins is altered by the stresses of cardiac surgery and heart failure. Understanding how the human heart attempts to protect itself in disease and how enkephalins work under these conditions, may prove valuable in the development of new drug therapy with synthetic drugs which mimic the action of enkephalins for heart protection during cardiac surgery, heart transplantation and ischemic heart disease. We will test whether specific enkephalins may be used to improve donor heart viability for transplantation by improving the duration and quality of preservation during storage. Understanding what happens to enkephalin production and metabolism in the failing hearts of patients may allow us to find new therapeutic targets in heart failure.Read moreRead less