Friday, January 23, 2009
Mechanisms of virus neutralization by Antibodies(Ab)
b) Ab inhibition of the interactions between the viral envelope protein and the cell-surface receptors is shown to occur after the virion has attached by binding via the receptors. Ab interference with any of these necessary links in a chain of events that lead to entry would constitute a neutralization mechanism.
c) Abs’ block of requisite interactions between viral and cell-membrane proteins would delay or prevent the penetration of the viral core into the target-cell cytoplasm. The virion may thus ultimately be destroyed through lysosomal degradation. In addition, Ab-mediated derouting of viruses that preferentially enter directly via the cell surface to a less permissive endosomal compartment may abrogate infectivity.
d) The intercalation of Ab in the fusion interface between the cell membrane and the envelope of a virus may block fusion at the cell surface, as illustrated, or in an endosome.
e) It has been conjectured that even a very low occupancy of antibody on the virion can cause global or internal changes by transmitting a signal across the viral envelope or outer layer. These hypothetical changes would allow the viral core to enter the cytoplasm but compromise further replicative steps
f) The neutralization of naked viruses could potentially differ from that of enveloped viruses.
Blogged @ 8:38 PM