FIG 6.

Relationship between infection of cells expressing mCD4 and sensitivity to MAbs targeting a quaternary epitope in the V1V2 region, PG9 (A) and PG16 (B). The association between infection of cells expressing mCD4 and sensitivity to neutralization by PG9 or PG16 was determined by using infectivity data as described previously (18). Each dot represents a different Env variant tested. The gray dotted line represents the threshold (10% relative infection) used to identify HIV-1 Env proteins that might be suitable for SHIV development.