Protecting Against Malaria Through Liver-resident Memory T Cells
Funder
National Health and Medical Research Council
Funding Amount
$1,196,853.00
Summary
We have shown that formation of liver-resident memory T cells (Trm), a newly discovered type of immune cells, can be induced by an innovative vaccination strategy called prime and trap for highly efficient protection against malaria in mice. Here, we will enhance prime and trap vaccination efficacy by defining the conditions that maximize liver Trm-mediated protection and will characterize simian and human liver Trm cells, paving the way to create the most efficient human malaria vaccine to date
Placental Malaria, Placental Function, Nutrient Transport And Fetal Growth Restriction
Funder
National Health and Medical Research Council
Funding Amount
$483,517.00
Summary
Malaria infection in the placenta impairs the baby's growth, probably by causing placental inflammation. We believe this inflammation interferes with the ability of placental cells to transport nutrients such as amino acids and glucose from mother to baby. We will test this by examining the expression of genes and proteins involved in nutrient transport in placental samples from pregnant women, and in cell lines, and will examine how malaria affects growth factors that control this process.
The Role Of The Innate Immune System In The Immunopathogenesis Of Malaria
Funder
National Health and Medical Research Council
Funding Amount
$82,554.00
Summary
Malaria is common worldwide, affecting 600 million people. As with many infectious diseases, it the severity of a malaria infection is not only dictated by the parasite, but also the body’s immune response to the infection. This study looks at cells that contribute to the immediate immune response in two major clinical syndromes of malaria affecting women and children: cerebral malaria and malaria of pregnancy. By understanding the immune response, we gain insights into how to limit disease.
Trafficking And Expression Of PfEMP1 On The Surface Of P.falciparum-infected Erythrocytes
Funder
National Health and Medical Research Council
Funding Amount
$558,189.00
Summary
Malaria causes over 2 million deaths each year. The parasite infects human red blood cells and expresses a virulence protein on the erythrocyte surface allowing it to adhere to the microcapillaries preventing clearance through the spleen. We aim to understand how the parasite is able to express this virulence protein on the parasite-infected red blood cell surface. Identification of the proteins involved will provide potential drug targets to develop novel antimalarial compounds and strategies.
Antimalarial Drugs In Pregnancy: Preclinical And Clinical Studies Of Conventional And Novel Agents
Funder
National Health and Medical Research Council
Funding Amount
$470,115.00
Summary
Women in malaria-endemic areas such as coastal PNG are at high risk of malaria in pregnancy. To prevent the substantially increased malaria-associated morbidity and mortality in mother and child, and because even asymptomatic infections can be deleterious, there has been a move to giving antimalarial drugs regularly during pregnancy regardless of the mother's clinical or parasitological status. In poor tropical countries, such treatment usually comprises safe and inexpensive agents such as chlor ....Women in malaria-endemic areas such as coastal PNG are at high risk of malaria in pregnancy. To prevent the substantially increased malaria-associated morbidity and mortality in mother and child, and because even asymptomatic infections can be deleterious, there has been a move to giving antimalarial drugs regularly during pregnancy regardless of the mother's clinical or parasitological status. In poor tropical countries, such treatment usually comprises safe and inexpensive agents such as chloroquine and Fansidar. There are two main issues with this approach. First, the efficacy of such conventional agents is waning and this increases the risk of break-through malaria. Second, there are few data on how the drugs are handled in pregnancy on which to base recommendations for treatment. We plan to collect information on the disposition and effectiveness of chloroquine and Fansidar in women with malaria in pregnancy in PNG that should allow a critical appraisal of the usefulness of current regimens in PNG and in other tropical countries where parasite resistance to these agents is emerging. Artemisinin combination therapy (ACT) in the form of a novel artemisinin drug and a longer-acting partner has been suggested as the most promising alternative therapy for malaria in pregnancy if conventional drugs fail. We plan to assess the safety of a leading ACT formulation, namely dihydroartemisinin and the chloroquine-like drug piperaquine (DHA-PQ), in animals before extending our studies to women with malaria in PNG. These latter studies will allow an evaluation of the safety and efficacy of DHA-PQ as novel therapy for malaria in pregnancy in PNG and other tropical countries.Read moreRead less
Iron Metabolism And The Cirrhotic Liver:studies On Iron Absorption And Hepatic Iron Kinetics
Funder
National Health and Medical Research Council
Funding Amount
$256,980.00
Summary
Patients with liver disease awaiting liver transplantation often have excess iron in the liver that aggravates the existing liver disease. We have shown that patients with cholestatic liver disease, (due to poor bile excretion), do not have much iron in the liver compared to those patients with hepatocellular cirrhosis, (where the liver cells are damaged). Why this is so is unknown. Iron is normally absorbed from the diet by with the help of special molecules in the small intestine, carried in t ....Patients with liver disease awaiting liver transplantation often have excess iron in the liver that aggravates the existing liver disease. We have shown that patients with cholestatic liver disease, (due to poor bile excretion), do not have much iron in the liver compared to those patients with hepatocellular cirrhosis, (where the liver cells are damaged). Why this is so is unknown. Iron is normally absorbed from the diet by with the help of special molecules in the small intestine, carried in the blood to the liver where it is used by the cells. We would like to study how the proteins that transport iron in the intestine function and see if this is a different in disease. We would also like to examine exactly which molecules are important in depositing iron in the liver in patients with cirrhosis. We will work on animal models of liver disease as well as humans. We will treat animals so that they have liver disease that resembles human subjects with cirrhosis. These treatments include (1) feeding the animals carbon-tetrachloride, a toxin which damages the liver cells and therefore causes hepatocellular liver injury, and (2) tying the bile duct which stops the flow of bile and this results in cholestatic liver injury. It is known which proteins takes iron into the normal liver cells but no one knows which molecules transport the iron in liver disease. We think they may be different, because when the liver becomes diseased, scarring occurs this results in cirrhosis. Molecules that could easily enter liver cells may now be too big to pass through the openings. These studies are important since they will suggest new treatments to patients with liver disease who are awaiting a liver transplant and the treatment will probably differ depending on which type of liver disease the patient has.Read moreRead less
Functional Genomic Analysis Of Exported DNA J Molecules In The Malaria Parasite Plasmodium Falciparum
Funder
National Health and Medical Research Council
Funding Amount
$529,698.00
Summary
Every day 3500 people die of malaria and more than 40% of the world s population is at risk. Malaria is one of the biggest scourges of mankind. This project aims to translate the available genomic data into functional insights using frontier technology to identify new intervention targets for P. falciparum infection. Developing novel targets against malaria is important from a humanitarian point of view, and also to safeguard Australia and its neighbouring regions against the social and economic ....Every day 3500 people die of malaria and more than 40% of the world s population is at risk. Malaria is one of the biggest scourges of mankind. This project aims to translate the available genomic data into functional insights using frontier technology to identify new intervention targets for P. falciparum infection. Developing novel targets against malaria is important from a humanitarian point of view, and also to safeguard Australia and its neighbouring regions against the social and economical implication of this disease. The malaria parasite seeks shelter from the host immune system by hiding in red blood cells, but at the same time it has to stay in contact with the blood environment. This is achieved by export of virulence factors onto the surface of malaria parasite-infected red blood cells, which are essential for the maintenance of malaria infection. Without these virulence factors the body's immune system can get rid of the malaria parasites by itself. For display on the surface the proteins have to pass several membranes and are transferred through the red blood cell. The whole transport and assembly process of the virulence factors into functional units is very complex and requires several helper and co-helper molecules. With the deciphering of the malarial genetic code it became obvious that the parasite displays an unusual large number of co-helper molecules, which are putatively exported into the red blood cell. We will generate transgenic parasites deficient in the expression of these exported co-helper proteins and assess their role on the pathogenesis of this debilitating infectious disease.Read moreRead less
Cholestasis And Hepatocyte Injury In Chronic Liver Disease
Funder
National Health and Medical Research Council
Funding Amount
$615,967.00
Summary
The aim of this project is to understand the consequences of long-term cholestasis or impaired bile excretion/flow on normal liver cells (hepatocytes) and to test whether specific bile acids can cause irreversible damage to hepatocytes leading to their transformation into pre-malignant cells and hepatocellular carcinoma (primary liver cancer). The results from this project will inform new strategies in screening, prevention and treatment of liver cancer in children and adults with cholestasis.
The greatest impact of Plasmodium falciparum malaria infection in Africa is on children and pregnant women. Malaria infected red blood cells stick to receptor molecules on cells lining blood vessels. The parasite produces a family of proteins called PfEMP1, expressed on the cell surface. These PfEMP1 proteins are responsible for the sticking, and are major targets of the host immune response to malaria. We have found two particular receptor molecules, sugars called chondroitin sulphate A (CSA) a ....The greatest impact of Plasmodium falciparum malaria infection in Africa is on children and pregnant women. Malaria infected red blood cells stick to receptor molecules on cells lining blood vessels. The parasite produces a family of proteins called PfEMP1, expressed on the cell surface. These PfEMP1 proteins are responsible for the sticking, and are major targets of the host immune response to malaria. We have found two particular receptor molecules, sugars called chondroitin sulphate A (CSA) and hyaluronic acid (HA), to be particularly important in sticking in the placenta, and have identified a PfEMP1 molecule which sticks to these. We will study the role of antibodies against the parasite, and against the CSA and HA molecules, in protection against malaria. We believe that African women develop these antibodies with increasing pregnancies, protecting themselves and their babies from malaria in later pregnancies, and that men will not have these antibodies. Pregnant women who have HIV-AIDS have greater susceptiblity to malaria. We will compare antibody responses in HIV+ and HIV- women to see if this is because they produce less protective antibodies. The PfEMP1 proteins are the product of var genes. We can compare parasites using the var genes they express to fingerprint them. We will examine the var gene expression by parasites from different patients, and by the parasites circulating in the blood or stuck in the placenta (in pregnant women) or in the brain, lung, gut and other organs (of children who have died of malaria) to see if the fingerprints of var gene expression differ between these different patients, or between different places in the same patient.Read moreRead less