In newborn rhesus macaques, a combination of neutralizing IgG1 human mAbs targeting gp120 (b12, 2G12) and gp41 (2F5, v4E10) prevented oral infection with SHIV in 50% of animals that received 2 doses of the combination at 1 h and 8-day post-challenge, while those that developed infection had slower disease progression and conserved CD4 + T cell counts [139]. Here, CD4 is linked to infection.