Challenges in Designing HIV Env Immunogens for Developing a Vaccine - Structure-Based Study of Viral Replication - page 341

Table 1. Conserved epitopes on the ENV that are targets for developing an
HIV vaccine

Env Region Targeted Epitope nAbs Non-nAbs Characteristics

gp120 CD4-Binding Site F105 15e These antibodies compete

(CD4BS) b12 21h with CD4 for binding to

559/64D Env. Not all of the CD4BS

650-D antibodies neutralize

448D primary isolates.

39.3
b3
b6
830D

CD4-inducible E51 17b Binding of Env to CD4

conformational X5 48D enhances the exposure of

epitope CG10 23E these epitopes. Most of

49E these antibodies neutralize

21C primary isolates as Fab and

not as the whole IgG.

Carbohydrate 2G12 Poorly immunogenic, and

dependent binding is dependent upon

epitope proper N-linked

glycosylation.

gp41 Epitopes in close 2F5 These antibodies interfere in

proximity to 4E10 membrane fusion and

viral membrane Z13 therefore prevent viral

entry. To date, these are
the most potent
neutralizing antibodies
identified.

Cluster I of gp41 Clone 3 Highly immunogenic

246-D epitope, but Clone 3 is the

only one of many mAbs
specific for this epitope
that has neutralizing
activity.

in preventing or controlling the HIV infection, the most commonly
used approach is to perform passive immunization using neutraliz-
ing mAbs in non-human primates. Emini and colleagues have shown
that chimpanzees were protected by an anti-gp120 V3 loop-specific