Immunobiology Of Carbohydrate Antigens In Xenotransplantation
Funder
National Health and Medical Research Council
Funding Amount
$563,554.00
Summary
Xenotransplantation, the transplanting of organs from other species, is now seen as a viable solution to the problem of lack of supply of suitable human donors. The recent production of genetically engineered pigs represented a critical step towards clinical xenotransplantation. However, other sugars still remain that cause rejection. This project examines the consequences of these sugars.
The Role And Function Of Macrophages In Cellular Xenograft Rejection
Funder
National Health and Medical Research Council
Funding Amount
$323,250.00
Summary
The long term objective of this project is to develop pig insulin secreting tissue as a treatment for type 1 diabetes. At present the main barrier to this is rejection. In paricular a type of white blood cell called macophages has an important role in causing the rejection seen in xenotransplantation (the transplantation of pig tissue into humans). Our reseach group has made novel observations which show that the way macrophages respond to a xenotransplant is different to the way it behaves to t ....The long term objective of this project is to develop pig insulin secreting tissue as a treatment for type 1 diabetes. At present the main barrier to this is rejection. In paricular a type of white blood cell called macophages has an important role in causing the rejection seen in xenotransplantation (the transplantation of pig tissue into humans). Our reseach group has made novel observations which show that the way macrophages respond to a xenotransplant is different to the way it behaves to the transplant of an organ from the same species. In the rejection of pig insulin secreting tissue, macrophages are able to respond in the absence of ongoing signals from T cells. This project aims to identify the receptors on macrophages that are responsible for this response. In particular those receptors that are important for facilitating the migration of macrophages to the transplant site and the receptors that allow macrophages to distinguish self from non-self will be analysed. Hopefully these receptors will be used as targets for new therapeutic agents that could be used to prevent the strong rejection response that occurs when pig insulin secreting tissue is transplanted into humans.Read moreRead less
Approaches To Allogeneic Chimerism For The Induction Of Transplantation Tolerance
Funder
National Health and Medical Research Council
Funding Amount
$212,036.00
Summary
All patients with organ failure who receive a transplant require lifelong immunosuppressive medications to prevent the body from rejecting the foreign tissue. Indefinite immunosuppressive therapy is associated with significant side-effects which include infections and cancers. In addition, long-term loss of the transplants due to slow rejection (chronic rejection) remains high. Achieving a state of immunological tolerance in which transplanted tissue is regarded as self, but reactivity to all ot ....All patients with organ failure who receive a transplant require lifelong immunosuppressive medications to prevent the body from rejecting the foreign tissue. Indefinite immunosuppressive therapy is associated with significant side-effects which include infections and cancers. In addition, long-term loss of the transplants due to slow rejection (chronic rejection) remains high. Achieving a state of immunological tolerance in which transplanted tissue is regarded as self, but reactivity to all other foreign tissues (e.g. harmful viruses, bacteria) remain normal, would solve all these problems. Tolerance would eliminate the need for immunosuppressive medications and prevent rejection of transplanted organs. The production of mixed bone marrow chimerism is a potent method of inducing tolerance. Chimerism is a state in which bone marrow tissue from two genetically different individuals coexists in one person. This can be achieved by bone marrow transplantation from a specific donor, and if chimerism is achieved, the recipient will accept all tissues from the bone marrow donor without the need for ongoing immunosuppressive therapy. This study will attempt to examine the use of different therapeutic reagents (e.g. antibodies alone or antibodies linked to idarubicin, a drug which prevent cells dividing) to develop safe protocols for the production of bone marrow chimerism and tolerance for routine clinical use in humans. The study will also examine different cellular components of the donor bone marrow which may induce tolerance.Read moreRead less
The Role Of T-cell Apoptosis In Transplantation Tolerance
Funder
National Health and Medical Research Council
Funding Amount
$173,380.00
Summary
Organ transplantation is the treatment of choice for patients with end-stage heart, lung, liver or kidney failure and there have been spectacular improvements in the early success of these procedures. However the 10 year graft survival rate has not changed much in the past 15 years. One way of overcoming this problem is to manipulate the immune system so that the transplant is accepted indefinitely. This is called tolerance and it works by giving intense immunosuppression for a short period so t ....Organ transplantation is the treatment of choice for patients with end-stage heart, lung, liver or kidney failure and there have been spectacular improvements in the early success of these procedures. However the 10 year graft survival rate has not changed much in the past 15 years. One way of overcoming this problem is to manipulate the immune system so that the transplant is accepted indefinitely. This is called tolerance and it works by giving intense immunosuppression for a short period so that the transplant is accepted indefinitely without the need for long term immunosuppression. The immune mechanism responsible for this phenomenon is complex and is poorly understood. This project aims to study the early events in the immune system that leads to transplantation tolerance. In particular, factors involved in programmed cell death in white blood cells will be studied. Specially bred mice that have blocks in the cell death mechanisms will used to determine what effects these blocks have on the ability to induce tolerance. Other mice that have been genetically altered to allow their white cells to be tracked will be used to study the fate of these cells. If the mechanisms involved in tolerance induction are better understood, then it will be possible to design specific immunosuppressive drugs that will be used to produce tolerance in transplant patients.Read moreRead less
Cross-reactive Anti-viral T Cells Mediate Allograft Rejection In Lung Transplantation.
Funder
National Health and Medical Research Council
Funding Amount
$379,563.00
Summary
In solid organ transplantation chronic viral infections can play a major role in causing graft dysfunction and-or loss. This study investigates the role of a specific population of immunological cells. These specific anti-viral immune cells are key controllers of viral infections and have also been implicated in mediating the destruction and-or rejection of a transplanted graft.
Many people with organ failure need a transplant to survive. Unfortunately most patients who would benefit from a transplant are unable to receive one because of the shortage of living or deceased donors. A possible solution to this shortage is to use animal organs. Pigs are the most suitable animal donor. This project aims to produce and test genetically modified pigs which can provide organs that will be resistant to rejection when transplanted into human recipients.