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Broadly neutralizing antibodies (bnAbs) bind and neutralize diverse HIV isolates and demonstrate protective effects in primate models and humans against specific isolates. To develop an effective HIV vaccine, it is widely believed that inducing these antibodies is crucial. However, the high somatic hypermutation in bnAbs and the limited affinity of HIV Env proteins for bnAb germline precursors suggest that extended antigen exposure is necessary for their production. Consequently, HIV vaccine research is exploring complex sequential vaccination strategies to guide the immune response through maturation stages. In this context, the exploration of the factors linked to the generation of these antibodies across diverse age groups becomes critical. In this study, we assessed the anti-HIV-1 neutralization potency and breadth in 108 aviremic adults and 109 aviremic children under 15 years of age who were receiving ART. We used a previously described minipanel of recombinant viruses and investigated the factors associated with neutralization in these individuals. We identified individuals in both groups who were capable of neutralizing viruses from three different subtypes, with greater cross-neutralization observed in the adult group (49.0% vs. 9.2%). In both groups, we observed an inverse association between neutralization breadth and the CD4+/CD8+ ratio, as well as a direct association with the time to ART initiation. However, we found no association with time post-infection, cumulative ART duration, or CD8+ cell levels. The present study demonstrates that children receiving antiretroviral therapy generate broadly neutralizing responses to HIV-1, albeit with lower magnitude compared to adults. We also observed that neutralization breadth is associated with CD4+/CD8+ levels and time to treatment initiation in both children and adults living with HIV-1. Our interpretation of these results is that a delay in ART initiation could have prolonged the antigenic stimulation associated with viral replication and thus facilitate the capacity to elicit long-lasting broadly neutralizing responses. These results corroborate prior findings that show that HIV-1-neutralizing responses can persist for years, even at low antigen levels, implying an HIV-1 vaccine may induce lasting neutralizing antibody response. [ABSTRACT FROM AUTHOR]

Objective: Late presenters (LP) for HIV care are associated with higher morbidity and mortality rates. Our aim was to describe the characteristics associated with LP among adolescents in Spain. Identification of particular features may help in the design of strategies for improvement. Methods: Late‐presenting adolescents diagnosed at 12–19 years of age and enrolled in the Spanish paediatric and adult HIV/AIDS cohorts (CoRIS‐CoRISpe) from 2004 to 2019 were selected. LP were defined as those presenting with CD4 count <350 cells/mm3 or an AIDS‐defining event in the 6 months following HIV diagnosis. Confirmed low CD4 count in the next 3 months and before antiretroviral treatment initiation defined confirmed LP (cLP). Results: Of 410 adolescents newly diagnosed with HIV, 303 (73.9%) had available data for assessing late presentation. Of these, 34.7% were LP and 23.7% were cLP. The median CD4 count for cLP was 235 cells/mm3 (interquartile range 122–285). In a multivariable analysis, adolescents at the highest risk of late presentation were early adolescents (age 12–14 years; odds ratio [OR] 6.50; 95% confidence interval [CI] 2.61–18.2), middle adolescents (age 15–17 years; OR 1.85; 95% CI 0.92–3.59), and adolescents born abroad (OR 1.71; 95% CI 0.97–3.00), particularly those of African origin (OR 3.08; 95% CI 1.38–6.79). Conclusions: One‐quarter of adolescents presented late for HIV care in Spain. Early adolescents, middle adolescents, and those born abroad presented a sevenfold, twofold, and twofold higher risk of being cLP, respectively. Enhancing the awareness of HIV risk and the access to care, especially for younger and foreign adolescents, could help reduce late presentation and tackle the adolescent HIV epidemic. [ABSTRACT FROM AUTHOR]