ABOVE: T cells (red) in the olfactory bulb of mice engage with antigens on vesicular stomatitis virus, leading to cell signaling (green) that ultimately prevents neuronal death.
E.A. MOSEMAN ET AL., SCI IMMUNOL, 5:EABB1817, 2020
Failure to smell fresh cut grass or a poo-laden diaper is, at least these days, a potential sign of COVID-19 infection. “People say things smell funny or they can’t smell at all,” says Harvard University neurobiologist Sandeep Datta. Reading about people’s experiences of anosmia, Datta wondered how SARS-CoV-2, the virus that causes COVID-19, might be having this effect. One possibility was that the virus attacks cells that line and support olfactory neurons in the nose. Alternatively, SARS-CoV-2 could be directly targeting the neurons themselves.
Datta’s and other researchers’ work—which so far includes genetic and cellular analyses in humans, rodents, and monkeys—suggests that mammalian olfactory neurons don’t have the right cell receptors for the virus to get ...