Extended Data Fig. 5: Layout and timeline of experiments for the pregnant females in Groups A–C and their offspring in Groups 7–11.

Sixteen pregnant female rhesus macaques at similar gestational stages were selected on the basis of having little or no serum reactivity to AAV-8 by ELISA. These animals were then divided into three groups depending on whether they were treated with recombinant forms of rh-3BNC117-IgG1. The Group A dams (n = 8) received no bNAb infusion and underwent cesarean (c)-section when their pregnancies reached term at gestational week 24. The only exceptions were dams rhA-1 and rhA-3, which delivered their babies vaginally ahead of schedule. The dams in Groups B and C (n = 4 each) were treated intravenously with 30 mg/kg of recombinant rh-3BNC117-IgG1-LS or rh-3BNC117-IgG1, respectively, at gestational week 22 and then underwent c-section two weeks later. The offspring of the dams in Groups A-C were transferred to the nursery after birth and then assigned to Groups 7–11. The infants in Groups 7–11 were treated intramuscularly (IM) with 2.0 × 10¹² genome copies ml^–1 of an AAV-8/rh-3BNC117-IgG1-LS vector at postnatal weeks 4, 8, or 12, as depicted.