Immunological and clinical findings suggestive of some immune dysfunction have been reported among HIV-exposed uninfected(HEU) children and adolescents. Whether these defects are persistent or transitory is still unknown. HEU pediatric population at birth, 12 months, 6-12 years were evaluated in comparison to healthy age-matched HIV-unexposed controls. Plasma levels of LPS, sCD14, cytokines, lymphocyte immunophenotyping and T-cell receptor excision circles (TREC) were assessed. HEU and controls had similar LPS levels, which remained low from birth to 6-12 yearsfor plasma sCD14, IL-2, IL-6, IL-7, IL-10, IL-12p70, IL-13, IL-17, IFN-gamma, TNF-alpha, G-CSF, GM-CSF and MCP-1, which increased from birth to 12 months and then decreased at 6-12 yearsand for TREC/10(6) PBMC at birth in HEU and controls. By contrast, plasma MIP-1 beta levels were lower in HEU than in controls (p=0.009) at 12 months, and IL-4 levels were higher in HEU than controls (p=0.04) at 6-12 years. Immune activation was higher in HEU at 12 months and at 6-12 years than controls based on frequencies of CD38+HLA-DR+CD8+T cells (p=0.05) and of CD38+HLA-DR+CD4+T cells (p=0.006). Resting memory and activated mature B cells increased from birth to 6-12 years in both groups. The development of the immune system in vertically HEU individuals is comparable to the general population in most parameters, but subtle or transient differences exist. Their role in influencing clinical incidences in HEU is unknown.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Fed Sao Paulo, Dept Pediat, Sao Paulo, SP, BrazilUniv Miami, Dept Med, Miami, FL USAUniversidade Federal de São Paulo, Departamento de Pediatria, Divisão de Infectologia Pediátrica, Rua Pedro de Toledo, 781, 9º andar, CEP 04039-032, Vila Clementino, São Paulo, SP, Brazil.FAPESP: 10/09701-3FAPESP: 10/09738-4Web of Scienc
