RESUMO
Over the last 20 years, the incidence of vertical HIV transmission has decreased from 25%-42% to less than 1%. Although there are no signs of infection, the health of HIV-exposed uninfected (HEU) infants is notoriously affected during the first months of life, with opportunistic infections being the most common disease. Some studies have reported effects on the vertical transfer of antibodies, but little is known about the subclass distribution of these antibodies. We proposed to evaluate the total IgG concentration and its subclasses in HIV+ mothers and HEU pairs and to determine which maternal factors condition their levels. In this study, plasma from 69 HEU newborns, their mothers, and 71 control pairs was quantified via immunoassays for each IgG isotype. Furthermore, we followed the antibody profile of HEUs throughout the first year of life. We showed that mothers present an antibody profile characterized by high concentrations of IgG1 and IgG3 but reduced IgG2, and HEU infants are born with an IgG subclass profile similar to that of their maternal pair. Interestingly, this passively transferred profile could remain influenced even during their own antibody production in HEU infants, depending on maternal conditions such as CD4+ T-cell counts and maternal antiretroviral treatment. Our findings indicate that HEU infants exhibit an altered IgG subclass profile influenced by maternal factors, potentially contributing to their increased susceptibility to infections.
Assuntos
Infecções por HIV , Lactente , Humanos , Recém-Nascido , Imunoglobulina G , Incidência , Contagem de Linfócito CD4 , Transmissão Vertical de Doenças InfecciosasRESUMO
Resumen Con la implementación de estrategias de cuidado perinatal, la tasa de transmisión vertical del virus de inmunodeficiencia humana (VIH) ha disminuido considerablemente en el mundo. A pesar de no mostrar cargas virales, los infantes expuestos al VIH no infectados (ENI) cursan en sus primeros meses de vida con mayores tasas de morbimortalidad. Esto se relaciona con enfermedades infecciosas por microorganismos oportunistas y menor respuesta a las vacunas en comparación con infantes sin exposición al virus, lo que sugiere alteraciones en su sistema inmunitario. En esta revisión abordamos diferentes evidencias de alteraciones en las respuestas inmunitarias innatas y adaptativas de infantes ENI que pudieran explicar esta disfuncionalidad inmunitaria. Adicionalmente, este conocimiento ayuda a entender cómo se desarrolla el sistema inmunitario desde los primeros momentos de gestación que servirán para encontrar alternativas de manejo y terapias para el bienestar de los infantes con esta condición.
Abstract With the implementation of perinatal care strategies, the rate of vertical transmission of human immunodeficiency virus (HIV) has decreased considerably worldwide. Despite the absence of viral loads, infants exposed to HIV not infected during gestation have higher morbidity and mortality rates. This is found to be related to infectious diseases by opportunistic microorganisms and lower response to vaccines in their first months of life compared to non-HIV exposed infants, suggesting alterations in their immune system. In this review we address different evidence of alterations in the innate and adaptive immune responses of HIV exposed infants that could explain their immune dysfunctionality. Additionally, this knowledge helps to understand how the immune system develops from the early stages of gestation and will serve to find management alternatives and therapies for the welfare of the infants with this condition.
