Immune escape and tropism of HIV.

HIV-1 cell tropisms are partly determined by the hypervariable loops V1/V2 and V3 in gp120, which also contain epitopes for neutralizing antibodies. Mutations conferring tropism changes can result in escape from neutralization and vice versa. We examine whether variant viruses that can colonize new cell types and simultaneously escape neutralizing antibodies have an enhanced advantage in vivo.