This week in animal research 120615
An antibody that targets the immune system cells that cause type I diabetes has been shown to slow the development of the condition in mice. BL-9020 targets a specific receptor on the 'natural killer' cells of the immune system, which play a critical role in the destruction of insulin-secreting beta cells in the pancreas.
In humans this treatments could be used to treat the disease in early stage patients when beta cell function in the pancreas has not been completely destroyed.
Blocking "trigger" signals that enable breast cancer cells to spread to the lungs reduced the number of secondary tumours by up to two thirds in mice. The majority of human deaths due to breast cancer are caused by tumours spreading to other parts of the body.
Scientists at the University of Edinburgh discovered that one type of immune system cell called macrophages can actually help breast cancer cells to spread around the body. By blocking the signals that allow macrophages and cancer cells to communicate, they were able to reduce the cancer spread.
Prof Jeffrey Pollard, the centre’s director, said: “Our findings open the door to the development of treatments that target the tumour microenvironment, which may stop the deadly progression of breast cancer in its tracks.”
Scientists have found wild chimpanzees drinking fermented palm sap in Guinea, West Africa. The animals were using a leafy tool to sponge the alcohol, which is up to 6.9% strength. It opens up questions of whether our enjoyment of a drink is rooted in the activities of our evolutionary ancestors.
Dr Kimberley Hockings, from Oxford Brooks University, wrote: “Some of the chimpanzees at Bossou consumed significant quantities of ethanol and displayed behavioural signs of inebriation.
“Researchers rarely collected detailed behavioural data before versus after exposure to ethanol, but some drinkers rested directly after imbibing fermented sap.”
Heartburn drug could increase heart attack risk. Proton pump inhibitors (PPI) are one of the commonly prescribed drugs – around 8 million prescriptions in the UK each year plus over the counter sales - but it increases by 16-21% the risk of heart attacks. However, the study could not definitively prove the drugs were causing the heart attacks; it could be that the patients taking the drugs are simply sicker and more likely to get a heart attack. PPI drugs work by blocking the actions of cells called proton pumps, which produce stomach acid and animal studies and cell cultures showed that PPIs led to a drop in the level of nitric oxide, causing vessels to narrow and inflame.
Scientists find mutation that protects against ‘mad cow’ disease after studying cannibal group. The researchers discovered the mutation after studying the genes of the Fore people of Papua New Guinea who until recently had practised a form of cannibalism where a related disease, kuru, was transmitted by eating the brain tissue of the dead. The mutation that confers long- term resistance to kuru occurs in the gene for a prion protein. When researchers made the same change in the prion gene of laboratory mice they found that they became 100 per cent resistant to kuru and all forms of Creutzfeldt-Jakob disease (CJD), including variant CJD – the human form of bovine spongiform encephalopathy (BSE). Work is now on-going to understand the molecular basis of this effect which are expected to provide key insights into how misshapen proteins develop in the brain and cause the common forms of dementia, thereby guiding us to new treatments in the years ahead.
“we were expecting the mice to show some resistance to disease,” said Emmanuel Asante, who led the work at the MRC Prion Unit in the Institute of Neurology at University College London. “However, we were surprised that the mice were completely protected from all human prion strains. The result could not have been clearer or more dramatic.”
Mysterious new disease posing ‘emergent global threat for humans’ is carried by mosquitoes, shows study in mice. First described in 1990 and identified in 2008, the Rickettsia felis bacteria, also known as cat-flea typhus, cause symptoms similar to many bacterial infections, such as fever. A study in which mosquitoes were fed on Rickettsia felis-infected mice found that the insects were able to transmit the disease. Even when it was thought that Rickettsia felis was only transmitted by fleas and ticks, the disease was considered by the Centres for Disease Control and Prevention as “representing a high potential risk for public health”, it has been described on nearly every continent, except for Antarctica.