Abstract Body

Despite the highly-successful use of antiretroviral (ART)-based prevention for reduction of mother to child transmission (MTCT), as of 2017, 180,000 children continue to become infected with HIV-1 annually. Moreover, the fetal toxicities and prematurity associated with combination ART use in pregnancy are continuing to come to light. Pregnancy and the postpartum period are high risk for acute HIV acquisition, which translates into to high risk for HIV transmission to the developing fetus and breastfeeding infant. HIV variants transmitted perinatally have been demonstrated to be resistant to neutralization by concurrently circulating maternal antibodies, Thus, strategies that could synergize with ART to further reduce HIV MTCT during pregnancy may include temporary enhancement of autologous virus neutralization and targeted induction of functional antibodies that efficiently cross the placental barrier, which may be achievable with currently available HIV-1 vaccines. Furthermore, the pediatric HIV epidemic is bi-modal, with a peak in the neonatal period and a renewed high-risk period in adolescence following sexual debut. Therefore, vaccines that will eliminate the HIV epidemic will require administration during childhood. The early life immune system represents a unique immune landscape that could potentially be harnessed for qualities that are needed for the elicitation of protective immunity. In fact, recent reports have demonstrated that HIV-infected children develop broadly-neutralizing antibodies at a higher frequency and faster pace than that of HIV-infected adults. Intriguingly, the broadly-neutralizing antibodies identified in HIV-infected children have lower levels of somatic mutation than that of adults. Moreover, immunization strategies that aim for long-term development of protective immunity are well-suited for integration with the pediatric vaccine schedule, while immediate protection in the breastfeeding period can be achieved through concurrent passive administration of a potent broadly-neutralizing antibody. Therefore, enhancing and leveraging maternal and infant HIV immunity through novel passive and active immunization strategies provide renewed hope for ending the HIV-1 epidemic at the earliest stages of life.