Sara Cherry

University of Pennsylvania, USA

In 2006 Cherry joined the Perelman School of Medicine at the University of Pennsylvania. Here she combined her experience with high-throughput RNA interference (RNAi) screening with other cell-based screening techniques. Cherry studies viral pathogenesis, which includes both the ways viruses replicate and the anti-virus mechanisms within host cells. She is interested in how viruses hijack the machinery within a cell whilst evading their defence mechanisms. She primarily studies arthropod–borne viruses that impact RNA, including West Nile virus and Zika virus, as well as alphaviruses and bunyavirales. Arthropod-borne viruses contain very little genetic information (around 11 kilobytes), but can infect and replicate in a variety of hosts. Her research makes use of the model organism drosophila, high-throughput screening, functional genomics and forward genetics to better identify the genes that impact the life cycle of a virus. In 2017 she demonstrated an inhibitor to Zika virus, a mosquito-borne virus that had previously evaded treatment. Zika virus enters human cells through endocytosis, and bind to the cell's outer membrane via the clathrin. Cherry demonstrated that the antiviral Nanchangmycin restricts this mode of entry. Alongside her work in virology, Cherry has started to screen acute leukaemia patients to better understand how they will respond to advance therapeutics.

During the COVID-19 pandemic Cherry looked to identify novel therapeutic strategies, making use of her extensive small molecule library to identify chemical compounds that are active against SARS-CoV-2. She has investigated remdesivir, an antiviral that was developed for the Ebola virus disease, and chloroquine, an antimalarial medication. She used the high-throughput screening facility at the biosafety level-3 laboratory at the University of Pennsylvania to screen thousands of drugs at a time. Remdesivir is a nucleoside analogue that tries to stop the spread of the virus by forcing it to make mistakes when replicating its RNA, causing the strands themselves to break. She has also considered therapies that prevent the virus from ever entering cells, either through the modification of the virus or the host itself. The treatment may also come in the form of an interferon. To determine which treatments will be most appropriate, Cherry looks to identify which proteins SARS-CoV-2 makes use of for infection. As the availability of N95 masks decreased, Cherry purchased several powered air-purifying respirators (PAPRs) battery-driven hoods that circulate filtered air for members of her research team.