Chiometry of entry. For example, if in Eq. (13) we have that p1 p2 1 and p3 v1, then T 3. If the virion and target cell are attached by three trimers, if one of those trimers is disable, the two remaining trimers will spontaneously disable. The stoichiometry of entry has yet to be rigorously determined, but it is most probably greater than one [32]. To analyze neutralization experiments we treat