Defining The Mechanisms That Regulate Effective Long-term Anti-viral Immunity
Funder
National Health and Medical Research Council
Funding Amount
$547,315.00
Summary
Human cytomegalovirus (HCMV) is a common human pathogen which normally causes a mild or even asymptomatic infection. However, in immunocompromised individuals, HCMV causes severe disease whose manifestations include chorioretinitis, interstitial pneumonia and hepatitis. Similarly, in neonates lacking a fully mature immune system, HCMV causes severe morbidity. Vaccines that protect against HCMV induced cytomegalic inclusion disease have been designated Level I (most favourable) due to the predict ....Human cytomegalovirus (HCMV) is a common human pathogen which normally causes a mild or even asymptomatic infection. However, in immunocompromised individuals, HCMV causes severe disease whose manifestations include chorioretinitis, interstitial pneumonia and hepatitis. Similarly, in neonates lacking a fully mature immune system, HCMV causes severe morbidity. Vaccines that protect against HCMV induced cytomegalic inclusion disease have been designated Level I (most favourable) due to the prediction that they could save lives and prevent life-long disability. Similarly, therapies that prevent and-or reduce HCMV reactivation will significantly improve the prognosis of transplant and AIDS patients. The murine CMV (MCMV) infection model has provided important insights as to how the immune system controls infection, and the mechanisms utilized by the virus to circumvent these processes. The design of effective therapies and vaccines requires a thorough understanding of the mechanisms required to generate and maintain long-lasting anti-viral responses. The studies outlined in this proposal aim to define the impact of specific components of the immune system n the generation, maintenance and effectiveness of anti-viral immunity. The well characterized MCMV model will be used to address these issues.Read moreRead less
Targeting Vitamin-reactive T Cells For Enhanced Immunity
Funder
National Health and Medical Research Council
Funding Amount
$2,590,576.00
Summary
A specialised set of T cells called mucosal-associated invariant T (MAIT) cells react against bacteria and yeast, and reside at mucosal sites where the body's immune defences are often breached, e.g. respiratory tract and intestinal mucosa. This study seeks to define the molecular signals driving the function of MAIT cells, particularly during infections. This information may lead to methods tailored to manipulating MAIT cells therapeutically.
Infection, Immunity And Immigration Models For Prevention And Control Of Infectious Diseases In Refugees
Funder
National Health and Medical Research Council
Funding Amount
$290,615.00
Summary
Australia accepts refugees on humanitarian grounds, with a high proportion of these currently from Africa and the Middle East and many have serious infections such as TB or malaria. The outcomes of refugee children with serious infections, and the relationship of these outcomes to a range of cultural, socio-demographic and clinical factors have not been widely studied in refugees. This research will enable development of a model for optimal care of refugee children with serious illness.
Antigen Dose And TCR Repertoire In CD8+ T Cell Immunodominance Hierarchies
Funder
National Health and Medical Research Council
Funding Amount
$558,920.00
Summary
The CD8+, or killer , T lymphocytes (white blood cells) are the hit men of immunity, recirculating continually around the body to eliminate other cells that are dangerous because they are cancerous or infected with a virus. A major difficulty is that killer T cells also exert selective pressures that cause viruses and tumours to mutate and thus avoid immune control. This is a particularly serious problem for RNA viruses that readily mutate as they divide. These include the human immunodeficiency ....The CD8+, or killer , T lymphocytes (white blood cells) are the hit men of immunity, recirculating continually around the body to eliminate other cells that are dangerous because they are cancerous or infected with a virus. A major difficulty is that killer T cells also exert selective pressures that cause viruses and tumours to mutate and thus avoid immune control. This is a particularly serious problem for RNA viruses that readily mutate as they divide. These include the human immunodeficiency virus (HIV) that causes AIDS and, while the mutations that are most important with influenza viruses are those that modify viral surface proteins recognized by antibodies, such T cell escape mutants can also be a problem with influenza. The other reason why there is particular interest in promoting CD8+ T cell-mediated immunity to influenza is that the killer T cells are very cross-reactive. We have shown that vaccination approaches that prime mouse CD8+ T cells to resist influenza A viruses circulating currently in humans will also protect against the highly lethal, and dangerous H5N1 bird 'flu. The present flu vaccines only stimulate antibodies, so there is interest in the possibility of a major re-design. The CD8+ T cells recognize tiny elements (peptides) of the virus or tumour bound in the tip of our own transplantation, or class I major histocompatibility complex (MHCI) molecules. These pMHCI complexes are called epitopes. The focus here is on the use of novel genetic engineering strategies to find out how, when the virus mutates to disrupt the major epitopes seen by killer T cells, other minor epitopes can be abnormally emphasized in a way that promotes effective immune control. As we work on this with the relatively simple and safe influenza model we will concurrently develop strategies that may be of value in HIV and tumour immunity. Solving this problem could prove to be a substantial advance in the design of vaccines and immunotherapy approaches.Read moreRead less
Improving Adaptive Anti-viral Responses: A Key To Eliminating Persistent Viral Infection
Funder
National Health and Medical Research Council
Funding Amount
$402,391.00
Summary
Cytomegalovirus (CMV) can cause a persistent infection that can result in adverse clinical outcomes. Our previous work established that suboptimal adaptive immunity is responsible for viral persistence. This proposal will define the defect in adaptive immunity, its causes and how to improve it. The understanding gained from the proposed studies will provide crucial information for the development of improved anti-viral therapies and vaccines.
Innate Immunity In Premature Infants: The Role Of Toll Like Receptors In Susceptibility To Infection
Funder
National Health and Medical Research Council
Funding Amount
$440,312.00
Summary
Premature infants are extremely vulnerable to severe infection in early life. This study will examine how well premature infants mount an initial immune response against infection (innate immunity) compared to infants born on time and adults. This study will also look at factors that affect this response and whether we can predict which babies will develop severe infection or other complications. This information will help develop new strategies to treat and prevent infections in these infants.
Chronic infections and cancers are major causes of global disease burden. Harnessing the immune system to combat these diseases has proven difficult and cumbersome to date. We invented a new technology to boost the ability of the immune system to fight chronic infections such as AIDS and Hepatitis C. This involves using someone�s own blood treated with sets of short proteins. We term this therapy Overlapping Peptide Pulsed Autologous CelLs (OPAL). This shows great promise in robust animal models ....Chronic infections and cancers are major causes of global disease burden. Harnessing the immune system to combat these diseases has proven difficult and cumbersome to date. We invented a new technology to boost the ability of the immune system to fight chronic infections such as AIDS and Hepatitis C. This involves using someone�s own blood treated with sets of short proteins. We term this therapy Overlapping Peptide Pulsed Autologous CelLs (OPAL). This shows great promise in robust animal models. We now propose to refine this technique in animals in preparation for human clinical trials.Read moreRead less
Understanding The Role Of CD4 T Cells In Viral Infection: A Means Of Improving Anti-viral Immunotherapy.
Funder
National Health and Medical Research Council
Funding Amount
$672,009.00
Summary
Development of therapies to prevent and treat chronic infections is of the highest priority as they cause considerable clinical challenges and on-going health care costs. Efforts to improve treatment of chronic viral infections, such as those caused by HIV, hepatitis C virus and human cytomegalovirus, require a better understanding of the immune responses needed to control these viruses long-term. This proposal will investigate the role of CD4+ T cells in controlling chronic viral infection.
Bacterial Outer Membrane Vesicles As Immunomodulatory Agents In Helicobacter Pylori Infection
Funder
National Health and Medical Research Council
Funding Amount
$306,510.00
Summary
Chronic inflammation of the stomach is a hallmark of Helicobacter pylori infection, and is a precursor to peptic ulcer disease and cancer. Like many other bacteria, H. pylori sheds spherical blebs from its surface. These blebs bind to stomach cells in vitro and have been found in stomach biopsies of H. pylori-infected subjects. The aims of the work are to investigate the mechanisms whereby H. pylori blebs enter and disseminate within host cells, and how this may contribute to inflammation.