Differential potential for envelope glycoprotein-mediated steric shielding of host cell surface proteins among filoviruses

- Envelope glycoprotein-mediated steric shielding effects differ among filoviruses.
- The steric shielding efficiency is correlated with differential pathogenic potential.
- Overall properties of the GP molecule are important for efficient shielding.

The viral envelope glycoprotein (GP) is thought to play important roles in the pathogenesis of filovirus infection. It is known that GP expressed on the cell surface forms a steric shield over host proteins such as major histocompatibility complex class I and integrin β1, which may result in the disorder of cell-to-cell contacts and/or inhibition of the immune response. However, it is not clarified whether this phenomenon contributes to the pathogenicity of filoviruses. In this study, we found that the steric shielding efficiency differed among filovirus strains and was correlated with the difference in their relative pathogenicities. While the highly glycosylated mucin-like region of GP was indispensable, the differential shielding efficiency did not necessarily depend on the primary structure of the mucin-like region, suggesting the importance of the overall properties (e.g., flexibility and stability) of the GP molecule for efficient shielding of host proteins.