Why Does the Omicron Variant Largely Spare Olfactory Function? Implications for the Pathogenesis of Anosmia in Coronavirus Disease 2019

Overview

Journal J Infect Dis

Publisher Oxford University Press

Specialty Infectious Diseases

Date 2022 Apr 25

PMID 35467743

Authors

Rafal Butowt

Katarzyna Bilinska

Christopher von Bartheld

Affiliations

Soon will be listed here.

Abstract

The omicron variant of severe acute respiratory syndrome coronavirus 2 causes much less olfactory dysfunction than the previous variants. There are several potential mechanisms for how omicron may change tissue tropism and spare olfactory function. The new mutations make omicron more hydrophobic and alkaline than previous variants, which may reduce penetration of the mucus layer. Overall, the new mutations minimally change receptor binding affinity, but entry efficiency into host cells is reduced in cells expressing transmembrane serine protease 2 (TMPRSS2). Because the support cells in the olfactory epithelium abundantly express TMPRSS2, these main target cells in the olfactory epithelium may become infected less by the new omicron variant.

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