Differential immunophenotype and proviral composition in young adults with perinatally acquired HIV

OBJECTIVE

To characterize the immune functionality and phenotype and the proviral composition of a cohort of young adults with perinatally acquired HIV (p-YA) from Argentina.

DESIGN

Cross-sectional study of 18 p-YA, 15 young adults with nonperinatally acquired HIV matched by age with p-YA and 14 adults with nonperinatally acquired HIV, matched by time from HIV diagnosis with p-YA, all from Argentina.

METHODS

Immune memory/effector phenotype, exhaustion, activation, PTK-7 and Ki-67 expression were evaluated by flow cytometry on natural killer (NK) and T cells. Total, intact and defective proviral (TP, IP and DP) HIV-DNA were measured in CD4 + T cells by IPDA. Soluble markers were determined by ELISA.

RESULTS

p-YA displayed lower expression of PD-1, higher levels of CD38 + CD4 + T cells and increased levels of naive T cells than control groups. Also, a trend of lower levels of IP HIV-DNA normalized to CD4 + T-cell counts and to the proportion of naive T cells was found in p-YA.

CONCLUSION

The higher frequency of naive CD4 + T cells in p-YA cannot be explained by elevated thymic activity nor by a higher T-cell proliferation rate. This imbalance could have been generated early in life and persisted during adulthood. Naive CD4 + T cells may not serve as a major viral reservoir in p-YA. Also, the lower PD-1 + CD4 + T-cell count suggests that p-YA did not present higher levels of exhaustion. These findings suggest that acquiring HIV perinatally may imply different challenges for proviral eradication.

Characterization of HIV-1 Reservoirs in Children and Adolescents: A Systematic Review and Meta-Analysis Toward Pediatric HIV Cure

OBJECTIVE

To conduct a comprehensive, systematic review of the profile of HIV-1 reservoirs in children and adolescents with perinatally acquired HIV infection.

STUDY DESIGN

Randomized and nonrandomized trials, cohort studies, and cross-sectional studies on HIV reservoirs in pediatric populations, published between 2002 and 2022, were included. Archived-drug resistance mutations (ADRMs) and the size of reservoirs were evaluated. Subgroup analyses were performed to characterize further the data, and the meta-analysis was done through random effect models.

RESULTS

Overall, 49 studies from 17 countries worldwide were included, encompassing 2356 perinatally infected participants (48.83% females). There are limited data on the quantitative characterization of viral reservoirs in sub-Saharan Africa, with sensitive methodologies such as droplet digital polymerase chain reaction rarely employed. The overall prevalence of ADRMs was 37.80% (95% CI 13.89-65.17), with 48.79% (95% CI 0-100) in Africa, 42.08% (95% CI 6.68-82.71) in America, 23.88% (95% CI 14.34-34.90) in Asia, and 20.00% (95% CI 10.72-31.17) in Europe, without any difference between infants and adolescents (P = .656). Starting antiretroviral therapy (ART) before 2 months of age limited the levels of HIV-1 DNA (P = .054). Participants with long-suppressed viremia (>5 years) had lower levels of HIV-1 DNA (P = .027). Pre- and post-ART CD4 ≤29% and pre-ART viremia ≥5Log were all found associated with greater levels of HIV-1 DNA (P = .038, P = .047, and P = .041, respectively).

CONCLUSIONS

The pooled prevalence of ADRMs is high in perinatally infected pediatric population, with larger proviral reservoir size driven by delayed ART initiation, a shorter period of viral suppression, and immunovirological failures. Thus, strategies for pediatric HIV functional cure should target children and adolescents with very early ART initiation, immunocompetence, and long-term viral suppression.

Evaluation of HIV-1 DNA levels among adolescents living with perinatally acquired HIV-1 in Yaounde, Cameroon: A contribution to paediatric HIV cure research in Sub-Saharan Africa

Background

With the advent of antiretroviral therapy (ART), most children living with HIV in sub-Saharan Africa (SSA) are growing toward adolescence, with scarcity of evidence on the size of viral reservoirs to enhance paediatric cure research strategies. This study aims to compare HIV-1 proviral DNA levels according to virological response among adolescents living with perinatally acquired HIV-1 (ALPHIV) and identify associated-factors in the Cameroonian context.

Methods

In this observational cohort study, HIV-1 RNA viremia and CD4+ T-cell count were assessed through RT-PCR and flow cytometry respectively at three time-points over 18 months of observation. At the third time-point, 80 randomly-selected participants were classified as with viremia (≥50 HIV-1 copies/mL; n = 40) or without viremia (<50 HIV-1 copies/mL; n = 40); immune-competent (≥500 CD4+ T cells/mm3) or immunocompromised (<500 CD4+ T cells/mm3). Among these participants, total HIV-1 DNA load was quantified through droplet digital PCR using Bio-Rad QX200.

Results

Of the 80 randomly-selected adolescents, median [IQR] age was 15 (13-17) years, 56.2% were female, duration on ART was 9.3 [5.4-12.2] years. Among the 40 viremic ones (median viremia 7312 [283-71482]) HIV-1 copies/ml, 75.0% (30/40) were in virological failure (≥1000 HIV-1 copies/ml), while median of CD4 T cells were 494 [360-793] cell/mm3 with 48.8% (39/80) immunocompromised. No significant variation in HIV-1 RNA viremia and CD4 T cell count was observed between the three time-points, and 13.7% (11/80) adolescents remained aviremic and immune-competent throughout (stable adolescents). A positive and moderate correlation (r = 0.59; p < 0.001) was found between HIV-1 DNA levels and HIV- 1 RNA viremia. Regarding the CD4 T cell count, a negative and weak correlation (r = -0.28; p = 0.014) was found with HIV-1 DNA loads only among adolescents with viremia. Starting ART within the first year of life, ART for over 9 years and aviremia appear as predictors of low HIV-1 DNA loads.

Conclusion

Among ALPHIV, high HIV-1 RNA indicates an elevated viral reservoir size, representing a drawback to cure research. Interestingly, early ART initiation and longer ARTduration lead to sustained viral control and limited HIV-1 reservoir size. As limited size of viral reservoir appears consistent with viral control and immune competence, adolescents with sustained viral control (about 14% of this target population) would be candidates for analytical ART interruptions toward establishing paediatric post-treatment controllers in SSA.

In-Depth Characterization of Full-Length Archived Viral Genomes after Nine Years of Posttreatment HIV Control

In the search for control of human immunodeficiency virus type 1 (HIV-1) infection without antiretroviral therapy, posttreatment controllers (PTCs) are models of HIV remission. To better understand their mechanisms of control, we characterized the HIV blood reservoirs of 8 PTCs (median of 9.4 years after treatment interruption) in comparison with those of 13 natural HIV infection controllers (HICs) (median of 18 years of infection) and with those of individuals receiving efficient antiretroviral therapy initiated during either primary HIV infection (PHIs; n = 8) or chronic HIV infection (CHIs; n = 6). This characterization was performed with single-genome amplification and deep sequencing. The proviral diversity, which reflects the history of past viral replication, was lower in the PTCs, PHIs, and aviremic HICs than in the blipper HICs and CHIs. The proportions of intact and defective proviruses among the proviral pool in PTCs were not significantly different from those of other groups. When looking at the quantities of proviruses per million peripheral blood mononuclear cells (PBMCs), they had similar amounts of intact proviruses as other groups but smaller amounts of defective proviruses than CHIs, suggesting a role of these forms in HIV pathogenesis. Two HICs but none of the PTCs harbored only proviruses with deletion in nef; these attenuated strains could contribute to viral control in these participants. We show, for the first time, the presence of intact proviruses and low viral diversity in PTCs long after treatment interruption, as well as the absence of evolution of the proviral quasispecies in subsequent samples. This reflects low residual replication over time. Further data are necessary to confirm these results. IMPORTANCE Most people living with HIV need antiretroviral therapy to control their infection and experience viral relapse in case of treatment interruption, because of viral reservoir (proviruses) persistence. Knowing that proviruses are very diverse and most of them are defective in treated individuals, we aimed to characterize the HIV blood reservoirs of posttreatment controllers (PTCs), rare models of drug-free remission, in comparison with spontaneous controllers and treated individuals. At a median time of 9 years after treatment interruption, which is unprecedented in the literature, we showed that the proportions and quantities of intact proviruses were similar between PTCs and other individuals. Unlike 2/7 spontaneous controllers who harbored only nef-deleted proviruses, which are attenuated strains, which could contribute to their control, no such case was observed in PTCs. Furthermore, PTCs displayed low viral genetic diversity and no evolution of their reservoirs, indicating very low residual replication, despite the presence of intact proviruses.

Analyzing Longitudinally Collected Viral Load Measurements in Youth With Perinatally Acquired HIV Infection: Problems and Possible Remedies

Human immunodeficiency virus (HIV) viral load (VL) is an important quantitative marker of disease progression and treatment response in people living with HIV infection, including children with perinatally acquired HIV. Measures of VL are often used to predict different outcomes of interest in this population, such as HIV-associated neurocognitive disorder. One popular approach to summarizing historical viral burden is the area under a time-VL curve (AUC). However, alternative historical VL summaries (HVS) may better answer the research question of interest. In this article, we discuss and contrast the AUC with alternative HVS, including the time-averaged AUC, duration of viremia, percentage of time with suppressed VL, peak VL, and age at peak VL. Using data on youth with perinatally acquired HIV infection from the Pediatric HIV/AIDS Cohort Study Adolescent Master Protocol, we show that HVS and their associations with full-scale intelligence quotient depend on when the VLs were measured. When VL measurements are incomplete, as can be the case in observational studies, analysis results may be subject to selection bias. To alleviate bias, we detail an imputation strategy, and we present a simulation study demonstrating that unbiased estimation of a historical VL summary is possible with a correctly specified imputation model.

Persistence of Unintegrated HIV DNA Associates With Ongoing NK Cell Activation and CD34+DNAM-1brightCXCR4+ Precursor Turnover in Vertically Infected Patients Despite Successful Antiretroviral Treatment

The quantification of proviral DNA is raising interest in view of clinical management and functional HIV eradication. Measures of all unintegrated HIV DNA (uDNA) forms in infected reservoir cells provides information on recent replication events that is not found from other proviral DNA assays. To evaluate its actual relevance in a cohort of perinatally-infected adult HIV patients (PHIV), we studied how peripheral blood mononuclear cell uDNA levels correlated with total HIV DNA (tDNA) and with overall replication or innate immune control parameters including NK cell activation/exhaustion and lymphoid turnover. Twenty-two PHIV were included, with successfully controlled HIV (HIV RNA <50 copies/mL) on combined antiretroviral therapy for mean of 8.7 ± 3.9 years. uDNA accounted for 16 [5.2-83.5] copies/µg and was strongly correlated with tDNA (ρ=0.700, p=0.001). Flow cytometric analysis of peripheral NK cells showed that CD69 expression was directly correlated uDNA (p=0.0412), but not with tDNA. Interestingly, CD56^-CD16⁺NK cells which include newly described inflammatory precursors and terminally differentiated cells were directly correlated with uDNA levels (p<0.001), but not with tDNA, and an inverse association was observed between the proportion of NKG2D⁺ NK cells and uDNA (ρ=-0.548, p=0.015). In addition, CD34⁺DNAM-1^brightCXCR4⁺ inflammatory precursor frequency correlated directly with uDNA levels (ρ=0.579, p=0.0075). The frequencies of CD56^-CD16⁺ and CD34⁺DNAM-1^brightCXCR4⁺ cells maintained association with uDNA levels in a multivariable analysis (p=0.045 and p=0.168, respectively). Thus, control of HIV-1 reservoir in aviremic patients on ART is an active process associated with continuous NK cell intervention and turnover, even after many years of treatment. Quantification of linear and circular uDNA provides relevant information on the requirement for ongoing innate immune control in addition to ART, on recent replication history and may help stratify patients for functional HIV eradication protocols with targeted options.

Characterization of drug resistance and the defective HIV reservoir in virally suppressed vertically infected children in Mali

BACKGROUND

In the perspective of ART-free HIV remission, vertically infected children treated with suppressive ART from early infancy represent an optimal population model to better understand the genetic complexity of the reservoir.

OBJECTIVES

To evaluate the proportion of defective viral population and the genotypic resistance patterns in cell-associated HIV DNA.

METHODS

In a cohort including 93 ART-treated vertically HIV-infected (VHIV) children in Mali with plasma HIV-1 RNA ≤50 copies/mL for at least 6 months, we studied total HIV DNA, percentage of defective genomes and resistance by reverse transcriptase and protease bulk sequencing from whole blood in dried blood spots.

RESULTS

Children had a median age of 9.9 years at the time of inclusion (IQR = 7.6-13.4) and 3.3 years (IQR = 2-7) at ART initiation; median ART duration was 5.5 years (IQR = 3.7-7.3). The median level of total HIV DNA was 470 copies/106 cells with one patient presenting undetectable HIV DNA (<66 copies/106 cells). We observed the presence of at least one stop codon in viruses from 34 patients (37%). The presence of stop codons was not correlated with the level of HIV DNA or duration of ART. We showed a high prevalence of HIV-1 resistance in DNA with 26% of children harbouring virus resistant to at least one NRTI and 40% to at least one NNRTI.

CONCLUSIONS

While these VHIV children were successfully treated for a long time, they showed high prevalence of resistance in HIV DNA and a moderate defective HIV reservoir.

Impact of Early Versus Late Antiretroviral Treatment Initiation on Naive T Lymphocytes in HIV-1-Infected Children and Adolescents - The-ANRS-EP59-CLEAC Study

Background

The early initiation of antiretroviral therapy (ART) in HIV-1-infected infants reduces mortality and prevents early CD4 T-cell loss. However, the impact of early ART on the immune system has not been thoroughly investigated in children over five years of age or adolescents. Here, we describe the levels of naive CD4 and CD8 T lymphocytes (CD4/CD8TN), reflecting the quality of immune reconstitution, as a function of the timing of ART initiation (early (<6 months) versus late (≥24 months of age)).

Methods

The ANRS-EP59-CLEAC study enrolled 27 children (5-12 years of age) and nine adolescents (13-17 years of age) in the early-treatment group, and 19 children (L-Ch) and 21 adolescents (L-Ado) in the late-treatment group. T lymphocytes were analyzed by flow cytometry and plasma markers were analyzed by ELISA. Linear regression analysis was performed with univariate and multivariate models.

Results

At the time of evaluation, all patients were on ART and had a good immunovirological status: 83% had HIV RNA loads below 50 copies/mL and the median CD4 T-cell count was 856 cells/µL (interquartile range: 685-1236 cells/µL). In children, early ART was associated with higher CD8TN percentages (medians: 48.7% vs. 31.0%, P = 0.001), and a marginally higher CD4TN (61.2% vs. 53.1%, P = 0.33). In adolescents, early ART was associated with low CD4TN percentages and less differentiated memory CD8 T cells. CD4TN and CD8TN levels were inversely related to cellular activation and gut permeability.

Conclusion

In children and adolescents, the benefits of early ART for CD8TN were clear after long-term ART. The impact of early ART on CD4TN appears to be modest, because pediatric patients treated late respond to HIV-driven CD4 T-lymphocyte loss by the de novo production of TN cells in the thymus. Our data also suggest that current immune activation and/or gut permeability has a negative impact on TN levels.

Clinical Trial Registration

ClinicalTrials.gov, identifier NCT02674867.

Initiating Antiretroviral Treatment Early in Infancy Has Long-term Benefits on the Human Immunodeficiency Virus Reservoir in Late Childhood and Adolescence

BACKGROUND

Early combined antiretroviral therapy (cART) limits the total HIV-DNA load in children. However, data on its impact in older children and adolescents remain scarce. This study compares HIV reservoirs in children (5-12 years) and adolescents (13-17 years) who started cART <6 months (early [E-] group) or >2 years (late [L-] group).

METHODS

The ANRS-EP59-CLEAC study prospectively enrolled 76 patients perinatally infected with HIV-1 who reached HIV-RNA <400 copies/mL <24 months after cART initiation, regardless of subsequent viral suppression (E-group: 27 children, 9 adolescents; L-group: 19 children, 21 adolescents). Total and integrated HIV-DNA were quantified in blood and in CD4+ T-cell subsets. A substudy assessed HIV reservoir inducibility after ex vivo peripheral blood mononuclear cell (PBMC) stimulation.

RESULTS

Total HIV-DNA levels were lower in early- versus late-treated patients (children: 2.14 vs 2.87 log copies/million PBMCs; adolescents: 2.25 vs 2.74 log; P < .0001 for both). Low reservoir was independently associated with treatment precocity, protective HLA, and low cumulative viremia since cART initiation. The 60 participants with undetectable integrated HIV-DNA started cART earlier than other patients (4 vs 54 months; P = .03). In those with sustained virological control, transitional and effector memory CD4+ T cells were less infected in the E-group than in the L-group (P = .03 and .02, respectively). Viral inducibility of reservoir cells after normalization to HIV-DNA levels was similar between groups.

CONCLUSIONS

Early cART results in a smaller blood HIV reservoir until adolescence, but all tested participants had an inducible reservoir. This deserves cautious consideration for HIV remission strategies.

Factors associated with immunosenescence during early adulthood in HIV-infected patients after durable efficient combination antiretroviral therapy

Perinatally HIV-infected patients face the consequences of both chronic infection effects per se and long-term combination antiretroviral therapy (cART) on immunosenescence. Aims of our study were to evaluate which factors independently contribute to immunosenescence in HIV-infected young adults with a very different HIV infection duration (perinatally HIV-infected young individuals -pHIVy- and age-matched non perinatally HIV-infected youths –npHIVy), after durable  efficient cART. We considered low thymic and bone marrow output, respectively evaluated by quantifying T-cell receptor excision circles (TRECs), K-deleting recombination excision circles (KRECs), and shorter telomeres lenght (TL) as surrogate biomarkers of immunosenescence. Twenty-one pHIVy and 19 npHIVy (with a mean HIV duration of 3–8 years) were included; mean age was 27 years for both groups. Immunosenescence biomarkers were comparable between pHIVy and npHIVy (despite longer HIV-infection, higher frequency of AIDS events, past cART-free periods and concomitant chronic viral infections in pHIVy). At the multivariate analysis, CD4+ was the only variable independently associated with TRECs and TL. Our data suggest that a good level of thymic activity can compensate the deleterious effects of past periods without cART, if HIV replication is suppressed for a sufficient time.

Total HIV DNA: a global marker of HIV persistence

Among the different markers of HIV persistence in infected cells, total HIV DNA is to date the most widely used. It allows an overall quantification of all viral forms of HIV DNA in infected cells, each playing a different role in HIV replication and pathophysiology. The real-time PCR technology is to date, a precise, sensitive and reproducible technology that allows the description of the distribution of HIV infected cells in blood and tissues. The objective of this review is to present some examples which show the interest to quantify total HIV DNA levels. This marker brought an undeniable and considerable contribution to reservoir studies. Many results, both in clinical and basic research, allowed to get a large overview of the distribution of infected cells in the body, at all stages of HIV disease and during therapy. Future clinical studies aiming at reducing HIV reservoirs will benefit from HIV DNA quantification in blood and tissues, in association with other markers of HIV reservoir activity.

New Highly Sensitive Real-Time PCR Assay for HIV-2 Group A and Group B DNA Quantification

HIV-2 infection is characterized by a very low replication rate in most cases and low progression. This necessitates an approach to patient monitoring that differs from that for HIV-1 infection. Here, a new highly specific and sensitive method for HIV-2 DNA quantification was developed. The new test is based on quantitative real-time PCR targeting the long terminal repeat (LTR) and gag regions and using an internal control. Analytical performance was determined in three laboratories, and clinical performance was determined on blood samples from 63 patients infected with HIV-2 group A (n = 35) or group B (n = 28). The specificity was 100%. The 95% limit of detection was three copies/PCR and the limit of quantification was six copies/PCR. The within-run coefficients of variation were between 1.03% at 3.78 log₁₀ copies/PCR and 27.02% at 0.78 log₁₀ copies/PCR. The between-run coefficient of variation was 5.10%. Both manual and automated nucleic acid extraction methods were validated. HIV-2 DNA loads were detectable in blood cells from all 63 patients. When HIV-2 DNA was quantifiable, median loads were significantly higher in antiretroviral-treated than in naive patients and were similar for groups A and B. HIV-2 DNA load was correlated with HIV-2 RNA load (r = 0.68; 95% confidence interval [CI], 0.4 to 0.8; P < 0.0001). Our data show that this new assay is highly sensitive and quantifies the two main HIV-2 groups, making it useful for the diagnosis of HIV-2 infection and for pathogenesis studies on HIV-2 reservoirs.

Gag-Specific CD8 T-Cell Proliferation Is Associated With Higher Peripheral Blood Levels of Transforming Growth Factor-β and Gut-Homing T Cells in Youths Perinatally Infected With Human Immunodeficiency Virus-1: The ANRS-EP38-IMMIP Study

Background

Gag-specific T lymphocytes play a key role in the control of human immunodeficiency virus (HIV) replication. Their restoration will be important for future reservoir targeting strategies. In this study, we aimed to identify immune correlates of Gag-specific CD8 T-cell proliferation in youths with perinatally acquired HIV-1 infection.

Methods

The ANRS-EP38-IMMIP study included youths of 15 to 24 years of age. Fifty-three were taking combination anti-retroviral therapy and aviremic at the time of the study and had undergone valid 5-6-carboxyfluorescein diacetate succimidyl ester-based flow cytometry T-cell proliferation assays. Plasma analytes were quantified by enzyme-linked immunosorbent assay or multiplex assays. Peripheral blood cells were phenotyped by flow cytometry. Logistic regression was used to study the association between Gag-specific T-cell proliferation and immune markers.

Results

Patients with Gag-specific CD8 T-cell proliferation had higher levels of plasma transforming growth factor (TGF)-β1, a lower proportion of naive cells among regulatory T cells (Tregs), and higher percentages of CD4 and CD8 T cells expressing the α₄β₇ integrin or CD161 molecule than those without a Gag-specific response. These associations were significant based on analyses including potential confounders.

Conclusions

Preserved Gag-specific CD8 T-cell proliferation was associated with higher TGF-β1 levels and increased percentages of T cells with a gut-homing phenotype at least 15 years after HIV infection during the perinatal period.

Total HIV-1 DNA, a Marker of Viral Reservoir Dynamics with Clinical Implications

HIV-1 DNA persists in infected cells despite combined antiretroviral therapy (cART), forming viral reservoirs. Recent trials of strategies targeting latent HIV reservoirs have rekindled hopes of curing HIV infection, and reliable markers are thus needed to evaluate viral reservoirs. Total HIV DNA quantification is simple, standardized, sensitive, and reproducible. Total HIV DNA load influences the course of the infection and is therefore clinically relevant. In particular, it is predictive of progression to AIDS and death, independently of HIV RNA load and the CD4 cell count. Baseline total HIV DNA load is predictive of the response to cART. It declines during cART but remains quantifiable, at a level that reflects both the history of infection (HIV RNA zenith, CD4 cell count nadir) and treatment efficacy (residual viremia, cumulative viremia, immune restoration, immune cell activation). Total HIV DNA load in blood is also predictive of the presence and severity of some HIV-1-associated end-organ disorders. It can be useful to guide individual treatment, notably, therapeutic de-escalation. Although it does not distinguish between replication-competent and -defective latent viruses, the total HIV DNA load in blood, tissues, and cells provides insights into HIV pathogenesis, probably because all viral forms participate in host cell activation and HIV pathogenesis. Total HIV DNA is thus a biomarker of HIV reservoirs, which can be defined as all infected cells and tissues containing all forms of HIV persistence that participate in pathogenesis. This participation may occur through the production of new virions, creating new cycles of infection and disseminating infected cells; maintenance or amplification of reservoirs by homeostatic cell proliferation; and viral transcription and synthesis of viral proteins without new virion production. These proteins can induce immune activation, thus participating in the vicious circle of HIV pathogenesis.

Gag-Specific CD4 T Cell Proliferation, Plasmacytoid Dendritic Cells, and Ethnicity in Perinatally HIV-1-Infected Youths: The ANRS-EP38-IMMIP Study

In perinatally HIV-1-infected youths living in France, we previously reported that Gag-specific CD4 and CD8 T cell proliferation is more frequently detected in patients of black ethnicity than in those of other ethnicities. We observed that black patients had higher levels of dendritic cells (DCs) than other patients. We aimed at studying the association of DC levels with Gag-specific T cell proliferation. The ANRS-EP38-IMMIP study is an observational study of youths aged between 15 and 24 years who were perinatally infected with HIV. A single blood sample was drawn for virological and immunological assays. Data from cART-treated 53 youths with undetectable plasma HIV RNA were analyzed. Gag-specific T cell proliferation was assessed by using a CFSE-based test. Peripheral blood myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells (pDCs) were phenotyped by flow cytometry. Plasma markers were quantified by ELISA or multiplex assays. Logistic regression was used for univariate and multivariate analyses. Patients with Gag-specific CD4 T cell proliferative responses had significantly higher percentages and absolute counts of mDCs and pDCs in the peripheral blood than nonresponding patients. Gag-specific CD4 and CD8 T cell proliferation was associated with lower plasma sCD14 levels. Plasma levels of IFN-α, TRAIL, and chemokines involved in T cell migration to secondary lymphoid organs were not associated with T cell proliferation. Multivariate analysis confirmed the association between Gag-specific CD4 T cell proliferation and pDC levels. In conclusion, DC levels are a robust correlate of the presence of Gag-specific T cell proliferation in successfully treated youths.

Transition of HIV-infected youths from paediatric to adult care, a Swedish single-centre experience

BACKGROUND

Transition of HIV-infected adolescents from paediatric care to adult care is vulnerable and entails a risk of treatment failure. Therefore, a Transitional Outpatient Clinic for HIV-infected adolescents and young adults was started in 2008. The aims were to describe the transition process and treatment results in a Swedish cohort of adolescents with HIV.

MATERIALS AND METHODS

A cross-sectional study of the adolescent and young adults with HIV at the clinic was performed in October 2013 and a 2-year follow-up at the end of 2015.

RESULTS

The 34 patients in care in October 2013 were a median of 19 years, 50% were female. Thirty-one out of 34 (91%) were perinatally infected. In 2013, 88% were on antiretroviral treatment (ART), for a median duration of 9 years, 74% were on a protease inhibitor-based regimen. Twenty-nine patients were followed-up at the end of 2015. Twenty-three were transferred to the Infectious Disease Clinic and the median age for transition was 19 years. At the end of 2015, 90% were treated with ART and 61% had an integrase inhibitor-based treatment. Of those treated with ART for more than 6 months, 90% (2013) and 96% (2015) had a viral load < 50 HIV RNA copies/mL, despite resistance problems and complicating social factors. These figures were higher than reported in other studies and similar to the treatment results in the adult HIV population in Sweden.

CONCLUSIONS

The present study showed that it is possible to achieve good treatment results in adolescents with HIV.

Gag-Specific CD4 and CD8 T-Cell Proliferation in Adolescents and Young Adults with Perinatally Acquired HIV-1 Infection Is Associated with Ethnicity - The ANRS-EP38-IMMIP Study

The ANRS-EP38-IMMIP study aimed to provide a detailed assessment of the immune status of perinatally infected youths living in France. We studied Gag-specific CD4 and CD8 T-cell proliferation and the association between the proliferation of these cells, demographic factors and HIV disease history. We included 93 youths aged between 15 and 24 years who had been perinatally infected with HIV. Sixty-nine had undergone valid CFSE-based T-cell proliferation assays. Gag-specific proliferation of CD4 and CD8 T cells was detected in 12 (16%) and 30 (38%) patients, respectively. The Gag-specific proliferation of CD4 and CD8 T cells was more frequently observed in black patients than in patients from other ethnic groups (CD4: 32% vs. 4%, P = 0.001; CD8: 55% vs. 26%, P = 0.02). Among aviremic patients, the duration of viral suppression was shorter in CD8 responders than in CD8 nonresponders (medians: 54 vs. 20 months, P = 0.04). Among viremic patients, CD8 responders had significantly lower plasma HIV RNA levels than CD8 nonresponders (2.7 vs. 3.7 log₁₀ HIV-RNA copies/ml, P = 0.02). In multivariate analyses including sex and HIV-1 subtype as covariables, Gag-specific CD4 T-cell proliferation was associated only with ethnicity, whereas Gag-specific CD8 T-cell proliferation was associated with both ethnicity and the duration of viral suppression. Both CD4 and CD8 responders reached their nadir CD4 T-cell percentages at younger ages than their nonresponder counterparts (6 vs. 8 years, P = 0.04 for both CD4 and CD8 T-cell proliferation). However, these associations were not significant in multivariate analysis. In conclusion, after at least 15 years of HIV infection, Gag-specific T-cell proliferation was found to be more frequent in black youths than in patients of other ethnic groups, despite all the patients being born in the same country, with similar access to care.

Influence of lifelong cumulative HIV viremia on long-term recovery of CD4+ cell count and CD4+/CD8+ ratio among patients on combination antiretroviral therapy

OBJECTIVE

We explored the impact of lifelong cumulative HIV viremia on immunological recovery during antiretroviral therapy, according to the timing of treatment initiation.

METHODS

We estimated lifelong cumulative HIV viremia in patients followed in the ANRS PRIMO cohort since primary infection, including 244 patients who started treatment during PHI and had at least one treatment interruption, and 218 patients who started treatment later but with no interruptions. The impact of cumulative viremia on current immunological status was analysed using linear and logistic regression models.

RESULTS

At the last visit on treatment, median CD4 cell count was 645 cells/μl in the early/intermittent treatment group (median time from infection 9.5 years, 4.8 years of continuous treatment since last resumption), and 654 cells/μl in the deferred/continuous treatment group (median time from infection 6.1 years, 3.0 years of continuous treatment). Only 36.1 and 39.8% of patients achieved a CD4/CD8 ratio of more than 1, respectively. Current CD4 cell count was not associated with cumulative HIV viremia in either group. In contrast, patients with high cumulative HIV viremia (>66th percentile vs. <33rd percentile) were less likely to achieve a CD4/CD8 ratio of more than 1 (26.8 vs. 43.3%, P = 0.003), even after controlling for the baseline CD4/CD8 ratio, treatment duration, sex and age. Much higher CD4 cell count and CD4/CD8 ratio were reached in early/continuous treatment, that is low viremia exposure group.

CONCLUSION

Our results underline the critical need in early-treated patients to maintain adherence, in order to limit cumulative HIV viremia and optimize immunological recovery, notably the CD4/CD8 ratio.

Paediatric European Network for Treatment of AIDS (PENTA) guidelines for treatment of paediatric HIV-1 infection 2015: optimizing health in preparation for adult life

The 2015 Paediatric European Network for Treatment of AIDS (PENTA) guidelines provide practical recommendations on the management of HIV‐1 infection in children in Europe and are an update to those published in 2009. Aims of treatment have progressed significantly over the last decade, moving far beyond limitation of short‐term morbidity and mortality to optimizing health status for adult life and minimizing the impact of chronic HIV infection on immune system development and health in general. Additionally, there is a greater need for increased awareness and minimization of long‐term drug toxicity. The main updates to the previous guidelines include: an increase in the number of indications for antiretroviral therapy (ART) at all ages (higher CD4 thresholds for consideration of ART initiation and additional clinical indications), revised guidance on first‐ and second‐line ART recommendations, including more recently available drug classes, expanded guidance on management of coinfections (including tuberculosis, hepatitis B and hepatitis C) and additional emphasis on the needs of adolescents as they approach transition to adult services. There is a new section on the current ART ‘pipeline’ of drug development, a comprehensive summary table of currently recommended ART with dosing recommendations. Differences between PENTA and current US and World Health Organization guidelines are highlighted and explained.

Paediatric HIV grows up: recent advances in perinatally acquired HIV

This review is an update focusing on the current status of paediatric HIV in the UK and Ireland. Successes in prevention of mother to child transmission are highlighted. The changing epidemiology of the UK cohort is summarised and the shift in emphasis of treatment guidelines beyond limiting short-term morbidity and mortality to ensuring optimal health status in adult life is discussed. Current and future challenges relating to an aging cohort, successful transition to adult services and the prospect of a lifetime on antiretroviral therapy (ART), as well as the possibility of ART-free survival are also considered. While numbers of HIV-infected children in the UK are now decreasing, lessons we have learned in the last 30 years from this relatively small cohort are increasingly applicable to the global paediatric HIV population.

Maraviroc 150 mg daily plus lopinavir/ritonavir, a nucleoside/nucleotide reverse transcriptase inhibitor-sparing regimen for HIV-infected naive patients: 48-week final results of VEMAN study

Non-conventional strategies with nucleoside/nucleotide reverse transcriptase inhibitor-sparing regimens in antiretroviral naive human immunodeficiency virus (HIV) -infected patients have been explored in clinical trials. A prospective, open-label, randomized (1:1), multicentre, proof-of-concept trial (VEMAN study, EUDRACT number 2008-006287-11) was conducted assigning HIV-infected naive patients to once-daily maraviroc plus lopinavir/ritonavir (MVC group) or to tenofovir/emtricitabine plus lopinavir/ritonavir (TDF/FTC group). Clinical and laboratory data were collected at baseline, and after 4, 12, 24, 36 and 48 weeks with the objective to evaluate the 48-week virological and immunological efficacy. HIV-1 DNA load and CD4(+) T-cell subsets were analysed on frozen peripheral blood mononuclear cells collected at baseline, 4 and 48 weeks to explore the trend in HIV reservoirs. Fifty patients were randomized and included in the analysis. During follow up, HIV-1 RNA decreased similarly in both groups and, at week 48, all patients in the MVC group and 22/24 (96%) in the TDF/FTC group had < 50 copies/ml of HIV-1 RNA. CD4(+) trend during follow up was higher in maraviroc-treated patients (MVC group: 286 (183-343) versus TDF/FTC group: 199 (125-285); Mann-Whitney U-test: p 0.033). A significant 48-week increase of CCR5(+) CD4(+) T cells and CD4(+) effector memory cells was observed among maraviroc-treated patients (Wilcoxon signed rank test: p 0.016 and p 0.007, respectively). No significant variations were found in naive and central memory CD4(+) T cells. Among naive patients with an R5 virus, treatment with maraviroc and lopinavir/ritonavir was shown to provide a virological response compared to a triple therapy and a greater immunological benefit.

Adherence to antiretroviral therapy in adolescents living with HIV: systematic review and meta-analysis

Objective:

Adolescent and young adult (AYA) populations (12–24 years) represent over 40% of new HIV infections globally. Adolescence is sometimes characterized by high-risk sexual behaviour and a lack of engagement with healthcare services that can affect adherence to antiretroviral therapy (ART). Despite adherence to ART being critical in controlling viral replication, maintaining health and reducing onward viral transmission, there are limited data on ART adherence amongst AYA globally. We undertook a systematic review and meta-analysis of published studies reporting adherence to ART for AYA living with HIV.

Design and methods:

Searches included Embase, Medline and PsychINFO databases up to 14 August 2013. Eligible studies defined adequate adherence as at least 85% on self-report or undetectable blood plasma virus levels. A random effects meta-analysis was performed and heterogeneity examined using meta-regression.

Results:

We identified 50 eligible articles reporting data from 53 countries and 10 725 patients. Using a pooled analysis of all eligible studies, 62.3% [95% confidence interval (CI) 57.1–67.6; I² : 97.2%] of the AYA population were adherent to therapy. The lowest average ART adherence was in North America [53% (95% CI 46–59; I² : 91%)], Europe [62% (95% CI 51–73; I² : 97%)] and South America [63% (95% CI 47–77; I² : 85%] and, with higher levels in Africa [84% (95% CI 79–89; I² : 93%)] and Asia [84% (95% CI 77–91; I² : 0%].

Conclusion:

Review of published literature from Africa and Asia indicate more than 70% of HIV-positive AYA populations receiving ART are adherent to therapy and lower rates of adherence were shown in Europe and North America at 50–60%. The global discrepancy is probably multifactorial reflecting differences between focused and generalised epidemics, access to healthcare and funding.

HIV-1 DNA concentrations and evolution among African HIV-1-infected children under antiretroviral treatment (ANRS 1244/1278)

OBJECTIVES

The objectives of this study were to describe the pretreatment HIV-1 DNA concentrations in children infected with HIV and to evaluate the impact of antiretroviral therapy (ART) on HIV-DNA concentrations.

METHODS

This was a retrospective analysis of all children followed up in the 'Programme Enfant Yopougon' cohort, Abidjan, Côte d'Ivoire, from 2000 to 2004, who had cryopreserved peripheral blood mononuclear cells (PBMCs) and plasma samples. HIV-DNA was measured using a real-time PCR assay. Mixed-model analysis was used to analyse the factors associated with change in HIV-DNA concentration.

RESULTS

The study included 121 children infected with HIV-1. The median age at inclusion was 6 years (IQR: 3.5-9) and children were at an advanced stage of HIV disease (46.6% and 20.3% presenting CDC stage B and CDC stage C, respectively). At baseline, the median HIV-DNA concentration was 3.4 log₁₀ copies/10(6) PBMCs (IQR: 3.1-3.6). Fifty-four children were initiated on ART during follow-up. After 24 months of ART, HIV-DNA load decreased by 0.32 (IQR: 0.08-0.57) log₁₀ copies/10(6) PBMCs. The only factor associated with the HIV-DNA decrease was a concomitant low HIV-RNA viral load result. Children with efficient ART had a 0.51 log₁₀ copies (IQR: 0.40-0.86) HIV-DNA decrease per million PBMCs.

CONCLUSIONS

HIV-DNA concentrations decreased following ART initiation in a large African paediatric cohort. This decline was exclusively associated with the decrease in ongoing replication level achieved. Our study points out that a strong adherence is needed for ART to be efficient on the viral reservoirs, and further reinforces that adherence support is also essential to diminish the reservoir.

Treatment Response in Association with Adherence Patterns to Highly Active Antiretroviral Therapy in Pediatric Patients with Perinatally Acquired HIV Infection

Background:

Assessment of longitudinal adherence patterns on virologic and immunologic responses to HAART in perinatally acquired HIV patients has not been studied.

Methods:

Perinatally infected pediatric HIV patients with adherence documented at least twice and corresponding viral load and T-cell (%) data measured during 2008-2009 were studied. Multiple adherence measures were utilized to identify patients with persistent adherence, nonadherence, or alteration of adherence. Virologic and immunologic outcomes were assessed.

Results:

Persistent adherence, nonadherence, and alteration of adherence to HAART were recorded in 41.9%, 8.1%, and 50.0% of 62 studied patients. Persistent adherence was associated with higher likelihood for persistent virologic suppression and lower risk for persistent virologic failure.

Conclusion:

Alteration of adherence to HAART is a significant predictor of persistent virologic failure and high viremia in perinatally infected HIV patients. Implementation of longitudinal adherence assessments may target patients with nonsustained adherence patterns and help decrease the risk for virologic failure and disease progression.

CCR5 antagonists: a therapeutic option in HIV-1 perinatally infected children experiencing virologic failure?

OBJECTIVE

The risk of virologic failure and selection of resistant strains remains a challenge in HIV-1 perinatally infected children. HIV-1 coreceptor usage was determined in HAART-failing children followed in Necker Hospital (Paris, France) in order to estimate the proportion of these patients who may benefit from CCR5-antagonists therapy.

METHODS

HIV-1 coreceptor usage was determined with the SVM(Geno2pheno10%) algorithm in 51 children with virologic failure after a median treatment exposure of 7.8 years.

RESULTS

CXCR4-tropic strains were found in 31.4% of the patients. CXCR4 usage was associated with high HIV-1 DNA (P=0.01), old age (P=0.02), long ART cumulative exposure (P=0.006), and previous exposure to high number of different drugs (P=0.03) and ART combinations (P=0.03) in univariate analysis. Selection of resistant viruses and current exposure to a darunavir-based HAART tended to be more frequent in the CXCR4 group compared with the children infected with CCR5-tropic strains (P=0.06). In multivariate analysis, CXCR4 usage was exclusively correlated with HIV-1 DNA (P=0.03), which accurately reflects the cumulative exposure to viral replication over the whole duration of HIV infection.

CONCLUSION

Two-thirds of HAART-failing children could benefit from CCR5 antagonists-based strategies, even in case of triple-class virologic failure. Such therapy should be discussed more appropriately at early stages of infection, when CCR5-tropic strains are most frequently isolated. However, before considering such strategies, further studies are needed to evaluate the efficacy and the tolerability of CCR5 antagonists in this pediatric population.