J Infect Dis. 2011 Nov;204 Suppl 3:S825-32. doi: 10.1093/infdis/jir295.
Impact of Ebola mucin-like domain on antiglycoprotein antibody responses induced by Ebola virus-like particles.
Abstract
Ebola
virus (EBOV) glycoprotein (GP), responsible for mediating host-cell
attachment and membrane fusion, contains a heavily glycosylated
mucin-like domain hypothesized to shield GP from neutralizing
antibodies.
To test whether the mucin-like domain inhibits the production and function of anti-GP antibodies, we vaccinated mice with Ebola virus-like particles (VLPs) that express vesicular stomatitis virus G,
wild-type EBOV GP (EBGP),
EBOV GP without its mucin-like domain (ΔMucGP),
or EBOV GP with a Crimean-Congo hemorrhagic fever virus mucin-like domain substituted for the EBOV mucin-like domain (CMsubGP).
EBGP-VLP immunized mice elicited significantly higher serum antibody titers toward EBGP or its mutants, as detected by western blot analysis, than did VLP-ΔMucGP.
However, EBGP-, ΔMucGP- and CMsubGP-VLP immunized mouse sera contained antibodies that bound to cell surface-expressed GP at similar levels.
Furthermore, low but similar neutralizing antibody titers, measured against a vesicular stomatitis virus (VSV) expressing EBGP or ΔMucGP, were present in EBGP, ΔMucGP, and CMsubGP sera, although a slightly higher neutralizing titer (2- to 2.5-fold) was detected in ΔMucGP sera.
We conclude that the EBOV GP mucin-like domain can increase relative anti-GP titers, however these titers appear to be directed, at least partly, to denatured GP.
Furthermore, removing the mucin-like domain from immunizing VLPs has modest impact on neutralizing antibody titers in serum.
To test whether the mucin-like domain inhibits the production and function of anti-GP antibodies, we vaccinated mice with Ebola virus-like particles (VLPs) that express vesicular stomatitis virus G,
wild-type EBOV GP (EBGP),
EBOV GP without its mucin-like domain (ΔMucGP),
or EBOV GP with a Crimean-Congo hemorrhagic fever virus mucin-like domain substituted for the EBOV mucin-like domain (CMsubGP).
EBGP-VLP immunized mice elicited significantly higher serum antibody titers toward EBGP or its mutants, as detected by western blot analysis, than did VLP-ΔMucGP.
However, EBGP-, ΔMucGP- and CMsubGP-VLP immunized mouse sera contained antibodies that bound to cell surface-expressed GP at similar levels.
Furthermore, low but similar neutralizing antibody titers, measured against a vesicular stomatitis virus (VSV) expressing EBGP or ΔMucGP, were present in EBGP, ΔMucGP, and CMsubGP sera, although a slightly higher neutralizing titer (2- to 2.5-fold) was detected in ΔMucGP sera.
We conclude that the EBOV GP mucin-like domain can increase relative anti-GP titers, however these titers appear to be directed, at least partly, to denatured GP.
Furthermore, removing the mucin-like domain from immunizing VLPs has modest impact on neutralizing antibody titers in serum.
- PMID:
- 21987758
- [PubMed - indexed for MEDLINE]
- PMCID:
- PMC3189980
