143 Pediatric HIV Infection

Abstract

Currently paediatric recommended antiretroviral therapy requires taking medications daily and indefinitely. Given the emergence of side effects, the individual genetic make-up of each patient and the robust ability of HIV to evolve, the success at present experienced by many patients on HAART is neither universal nor permanent. The exploration of alternative approaches, that could potentially be used for the long-term management of HIV infection in the absence of HAART, is particularly necessary for infected children who nowadays need to start antiviral treatment within the first months of life. Immunotherapy, aimed to restore immunological competence to HIV, thus allows extended periods without antiviral drugs, can represent a new promising approach. However, to date, no therapeutic HIV vaccine trials have been performed in children or adolescents. Undestanding conditions associated with a better development of HIV and vaccines specific immune responses in HIV vertical infected children would permit to define criteria for the enrolment of paediatric patients into a therapeutic HIV vaccine trial. We report as timing of HAART initiation is the major factor predicting the longevity of memory B and T cell responses in HIV-1 infected children. We show as diverse antiviral regimens are associated with different grade of magnitude of HIV-specific T cell responses. We analyze the role of viral replication at the time of immunization on B cell showing as ongoing HIV-1 replication has a significant impact on the physiological age-related decline of immature-transitional B-cells and can impair humoral responses to pandemic flu vaccine. Finally we report preliminary data on the first pediatric therapeutic vaccine trial.