Crystallographic Studies Of Non-canonical Peptides Binding To MHC Class I Molecules.
Funder
National Health and Medical Research Council
Funding Amount
$489,750.00
Summary
Virus infected cells and cancer cells are recognised and eliminated from our body by specialised cells called T-cell lymphocytes. This recognition process is the key step in the immune response and some fundamental questions in immunology are centred on the nature of this process. At the molecular level, the recognition is mediated by the specific interaction between proteins on the surface of the cells. On the T-cell lymphocyte, the T-cell receptor (TCR) binds specifically to a protein called t ....Virus infected cells and cancer cells are recognised and eliminated from our body by specialised cells called T-cell lymphocytes. This recognition process is the key step in the immune response and some fundamental questions in immunology are centred on the nature of this process. At the molecular level, the recognition is mediated by the specific interaction between proteins on the surface of the cells. On the T-cell lymphocyte, the T-cell receptor (TCR) binds specifically to a protein called the MHC on the surface of the target cell. The target cell can be a cancer cell, or an infected antigen presenting cell (specialised cells in the body which present protein fragments (peptides) on their surface via MHC). The structure of a TCR and TCR-MHC have been solved in terms of the shape of the molecules at atomic resolution, bringing detailed information on how these two proteins interact with each other. In this proposal the structural basis of antigen presentation and recognition in cell-mediated immunity will be determined by three-dimensional structures of different peptides on MHC by x-ray crystallography. Cell surface antigen presentation by MHC molecules is crucial for initiating the cellular immune response against invading pathogens and cancer. This proposal encompasses a combined biochemical, immunological, and biophysical approach to understand the range of ligands which can bind to MHC which are subsequently recognised by the TCR. To understand the antigenic properties of modified peptides at the structure level, the x-ray structure of MHC with modified bound synthetic peptides will be determined.Read moreRead less
Structural Investigations Of Bacterial Evasion Of IgA Mucosal And Systemic Immunity
Funder
National Health and Medical Research Council
Funding Amount
$488,812.00
Summary
Nose, throat and skin infections are often caused by streptococcal and staphylococcal bacteria, known as Strep Throat and Golden Staph. Infections can be life-threatening in newborns, the elderly or individuals with weak immune systems. These bacteria make proteins bind and inactivate immune proteins. Our research examines the structural basis for bacterial interactions with a key immune system protein (an antibody called IgA) and may lead to new prevention and treatment strategies.