Karen Louise Mossman is a Canadian virologist who is a professor of Pathology and Molecular Medicine at McMaster University. Mossman looks to understand how viruses get around the defence mechanisms of cells. She was part of a team of Canadian researchers who first isolated SARS-CoV-2.

Early life and education

Mossman studied molecular biology at the University of Guelph.^[1] She moved the University of Alberta for her graduate degree, where she studied poxviridae in the laboratory of Grant McFadden.^[1][2][3] She remained in the University of Alberta for the postdoctoral training, where she specialised in microbiology.^[1]

Career

Mossman joined McMaster University in 2001.^[4] In 2006 she was awarded the International Society for Interferon and Cytokine Research Christina Fleischmann Award.^[5] She served as Chair of the Department of Biochemistry from 2017. In 2019 Mossman was named the Associate Vice President of McMaster University.^[4][6] She looks to understand how viruses can elude the immune system of cells, including normal and cancer cells.^[1][7] She hopes to use this understanding to design novel antivirals and cancer therapies.^[8]

McMaster University has a large collections of bats, which harbour more zoonotic diseases than any other mammals. To tackle these infections, bats attempt to limit viral replication and the associated immunopathology.^[9] Mossman has studied how bats respond to disease, and identified that they have enhanced IRF3 antiviral responses.^[9][10] As the antiviral response of bats is considerably more active than that of humans, viruses which infect bats generate more viral proteins than typical viruses. As a result, when bat viruses infect humans cells, the immune response can be quickly overwhelmed.^[11] It was speculated that bats could serve as reservoirs of emerging coronaviruses.^[12] Mossman has studied the pathogenesis of Middle East Respiratory Syndrome.^[13][14]

During the COVID-19 pandemic, Mossman was part of a team of Canadian researchers who isolated the genome of SARS-CoV-2. To isolate a virus, samples are collected from infected patients, then provided an opportunity to grow in mammalian cells or on culture plates.^[15] To isolate SARS-CoV-2, Mossman and her laboratory cultured the virus on immunodeficient cells. In these cells, the virus was able to multiply at ease.^[16][17]

The isolated virus should allow for the development of a COVID-19 vaccine.^[18] In general, vaccinations for coronaviruses are difficult to create.^[13] As many coronaviruses exist in nature, their genetic recombination can result in the formation of novel viruses,^[19] making targets for vaccinations difficult to identify. Even when they are identified, the vaccinations can exacerbate the symptoms of disease, compromising the immune system of vaccinated patients.^[13][20] Like other coronaviruses, the SARS-CoV-2 that infects humans is remarkably similar to a coronavirus found in bats. In late March 2020 Mossman was funded by the Canadian Institutes of Health Research to study the pathogenesis of SARS-CoV-2 in human and bat cells, in an effort to create in vitro and in vivo models of infection.^[21] By understanding the antiviral responses of the spillover (human) and reservoir (bat) host cells, Mossman hopes to create animal models that permit the rapid testing of candidate vaccinations.

References