Building a death-defying islet beta cell [ 2000 - 2002 ]

Research Grant

Researchers: Dr Janette Allison (Principal investigator)

Brief description Building a death-defying islet beta cell Type I diabetes results when the cells that produce insulin (the islet beta cells) are killed by the immune system. The beta cell, like any other cell in the body, can be induced to die by activation of a process that leads to cell suicide. During this process, enzymes dismantle the structure of the cell and the remains are eaten by neighboring cells. In diabetes, the stimulus for beta cell suicide is provided by a number of agents most of which are made by the T cells of the immune system. Our aim is to interfere with this cell suicide process and engineer a beta cell that can resist T cell attack. Because genetically manipulated mice provide the flexibility we need to add and subtract genes from the beta cell we will use them as a model to build a death-defying beta cell. We will investigate three strategies. Firstly, cells will be engineered to express a molecule (CD30 ligand) which recognizes a protein on the surface of the attacking T cells and in so doing, sends a signal to the T cells to stop proliferating. Secondly, we will remove proteins (CD95, TNFRI) from the surface of the beta cell, that attacking T cells use to set in motion the cell suicide process. Thirdly, we will engineer beta cells that express inside themselves, cell death inhibitor proteins (Bcl-2, CrmA, p35) that can prevent the automatic process of cell suicide. It is our hope that studies with death-defying beta cells will find a new way to manipulate islet tissue for transplantation. In patients with diabetes, the beta cells have all been destroyed but the attacking T cells still remain. As a result, transplants of new beta cells are rapidly damaged. Beta cells that can resist ongoing immune attack may survive well enough to reverse the symptoms of diabetes. The success of this research could have an impact on a cure for diabetes.

Funding Amount $AUD 410,075.18

Funding Scheme NHMRC Project Grants

Notes Standard Project Grant