VN August 2020

Vetnews | August 2020 39 Bits and Bobs I Stukkies en Brokkies Tuberculosis spread from animals to humans may be greater than previously thought Tuberculosis spread from animals to humans may be greater than previously thought The number of human tuberculosis (TB) cases that are due to transmission from animals, as opposed to human-to-human transmission, may be much higher than previously estimated, according to an international team of researchers. The results could have implications for epidemiological studies and public health interventions. “Tuberculosis kills 1.4 million people every year, making it the most deadly disease arising from a single infectious agent,” said Vivek Kapur, professor of microbiology and infectious diseases and Huck Distinguished Chair in Global Health, Penn State. “India has the largest burden of human tuberculosis globally, with more than 2.6 million cases and 400,000 deaths reported in 2019. Additionally, the cattle population in India exceeds 300 million, and nearly 22 million of these were estimated to be infected with TB in 2017. institution, analysed tumour samples from dozens of gliomas in adults, children, and dogs to compare their molecular profiles. The researchers found a remarkable degree of similarity, particularly between paediatric and canine tumours. The locations of genetic mutations were often the same, as were disease processes, such as the way gliomas alter DNA’s ability to repair itself and the timing of when the mutations themselves arise. These findings, published as “Comparative Molecular Life History of Spontaneous Canine and Human Gliomas” in the journal Cancer Cell, are both significant and original. The paper demonstrates that changes that are critical for brain tumour formation, including genetic mutations and acquired modifications in gene activity, are similar between human and canine brain cancers. Understanding these complex changes is a fundamental first step. Using the knowledge they gained in their comparative approach, researchers are already beginning to develop and evaluate novel treatment approaches for brain cancer. In addition, the team’s findings support the use of dogs as a model for human gliomas, an especially important consideration given the difficulties of modelling cancer in the laboratory. Cells in a petri dish often fail to mirror the way cancer behaves in a patient’s body, and serious ethical issues are invoked when inducing cancers in healthy laboratory animals. Because gliomas arise spontaneously in dogs and because the current, standard treatments often do not meaningfully improve the prognosis, experimental therapies aimed at dogs can help identify treatments that could evolve into promising human clinical trials. Dogs’ shorter lifespans mean that canine cancer tends to develop in a more compressed timescale than in humans, which enables therapies to be tested and outcomes to be assessed more rapidly. Two such trials are currently ongoing at the veterinary college. The first uses a technology called H-FIRE (high-frequency irreversible electroporation) to destabilise and kill cancer cells with short, targeted bursts of electrical energy, causing an immune reaction that can “mop up” remaining cancer cells. Another large- scale collaboration, which recently received a share of a $9.2 million grant from the National Institutes of Health’s National Cancer Institute, is testing a molecularly targeted chemotherapy. The drug in the study targets proteins on the surface of glioma cells that had previously been shown to be nearly identical between human and canine gliomas. v (Source: https://vtnews.vt.edu ) Virginia Tech veterinary neurologist helps establish shared 'life history' ... <<< 38 >>> 40