Discordant Immune Response with Antiretroviral Therapy in HIV-1: A Systematic Review of Clinical Outcomes

Advances in Mechanism of HIV-1 Immune Reconstitution Failure: Understanding Lymphocyte Subpopulations and Interventions for Immunological Nonresponders

In individuals diagnosed with AIDS, the primary method of sustained suppression of HIV-1 replication is antiretroviral therapy, which systematically increases CD4+ T cell levels and restores immune function. However, there is still a subset of 10-40% of people living with HIV who not only fail to reach normal CD4+ T cell counts but also experience severe immune dysfunction. These individuals are referred to as immunological nonresponders (INRs). INRs have a higher susceptibility to opportunistic infections and non-AIDS-related illnesses, resulting in increased morbidity and mortality rates. Therefore, it is crucial to gain new insights into the primary mechanisms of immune reconstitution failure to enable early and effective treatment for individuals at risk. This review provides an overview of the dynamics of key lymphocyte subpopulations, the main molecular mechanisms of INRs, clinical diagnosis, and intervention strategies during immune reconstitution failure, primarily from a multiomics perspective.

Clinical outcomes and risk factors for immune recovery and all-cause mortality in Latin Americans living with HIV with virological success: a retrospective cohort study

INTRODUCTION

Immune reconstitution following antiretroviral therapy (ART) initiation is crucial to prevent AIDS and non-AIDS-related comorbidities. Patients with suppressed viraemia who fail to restore cellular immunity are exposed to an increased risk of morbidity and mortality during long-term follow-up, although the underlying mechanisms remain poorly understood. We aim to describe clinical outcomes and factors associated with the worse immune recovery and all-cause mortality in people living with HIV (PLWH) from Latin America following ART initiation.

METHODS

Retrospective cohort study using the CCASAnet database: PLWH ≥18 years of age at ART initiation using a three drug-based combination therapy and with medical follow-up for ≥24 months after ART initiation and undetectable viral load were included. Patients were divided into four immune recovery groups based on rounded quartiles of increase in CD4 T-cell count at 2 years of treatment (<150, [150, 250), [250, 350] and >350 cells/mm3 ). Primary outcomes included all-cause mortality, AIDS-defining events and non-communicable diseases that occurred >2 years after ART initiation. Factors associated with an increase in CD4 T-cell count at 2 years of treatment were evaluated using a cumulative probability model with a logit link.

RESULTS

In our cohort of 4496 Latin American PLWH, we found that patients with the lowest CD4 increase (<150) had the lowest survival probability at 10 years of follow-up. Lower increase in CD4 count following therapy initiation (and remarkably not a lower baseline CD4 T-cell count) and older age were risk factors for all-cause mortality. We also found that older age, male sex and higher baseline CD4 T-cell count were associated with lower CD4 count increase following therapy initiation.

CONCLUSIONS

Our study shows that PLWH with lower increases in CD4 count have lower survival probabilities. CD4 increase during follow-up might be a better predictor of mortality in undetectable PLWH than baseline CD4 count. Therefore, it should be included as a routine clinical variable to assess immune recovery and overall survival.

Association of Alcohol Consumption With CD4 Recovery After Antiretroviral Therapy Initiation in St. Petersburg, Russia

BACKGROUND

Delayed CD4 recovery after initiating antiretroviral therapy (ART) is a novel potential mechanism by which alcohol consumption leads to increased morbidity and mortality in people with HIV. We hypothesized that alcohol consumption at ART initiation is associated with slower CD4 recovery.

METHODS

We retrospectively analyzed 2 pooled longitudinal alcohol/HIV cohorts (2014-2019) in St. Petersburg, Russia. Eligible participants initiated the first ART during parent studies; had alcohol consumption assessed by the blood biomarker, phosphatidylethanol (PEth), at the last research visit before ART initiation; and had ≥1 CD4 count measurement before and after initiating ART. Participants were stratified by low, moderate, and high PEth (<8, 8-80, and >80 ng/mL, respectively). We used random-effects piecewise linear regression models to estimate CD4 recovery, defined as CD4 count change per 30 days after ART initiation, by the alcohol group.

RESULTS

Of 60 eligible participants, median age was 34 years and 28% were female. The median pre-ART PEth in the low, moderate, and high PEth groups were <8, 23, and 232 ng/mL, respectively. After starting ART, the CD4 count increased by 13.60 cells/mm3/mo (95% CI: 0.33 to 26.87) with low PEth, 0.93 cells/mm3/mo (95% CI: -6.18 to 8.04) with moderate PEth, and 2.33 cells/mm3/mo (95% CI: -3.44 to 8.09) with high PEth.

CONCLUSIONS

Among Russians with HIV, we observed faster CD4 recovery after ART initiation in those with low alcohol consumption compared with those with moderate and high alcohol consumption, as assessed by PEth. This analysis provides further evidence for the possible value of alcohol reduction interventions for people with HIV who are initiating ART.

Role of CD4 count estimation in the era of HIV-1 viral load among PLHIV

BACKGROUND

ART has improved the life expectancy of people living with HIV (PLHIV) by suppressing the virus and increasing CD4 count. Some PLHIV shows immune-virological discordant responses i.e. suppressed viral load to the undetectable level but still with immunological failure or good immunological response with virological failure. Immuno-virological response plays a key role to address treatment outcome, regimen change and management for people living with HIV. It is reported that PLHIV with discordant responses were found to be at an increased risk to develop AIDS and non-AIDS events related death.

AIMS & OBJECTIVE

To determine immuno-virological discordance amongst PLHIV on ART and its effect on mortality.

MATERIAL & METHOD

After getting institutional Ethics committee approval, total 1921 patients were included in the study who were on ART for at least 6 month or more and have at least two CD4 count tests results and were tested from July 2019 to June 2020. Retrospective analysis was done.

RESULTS

Total 1921 patients were included in study of which 1383 (72%) showed immuno-virological concordance & 538 (28%) showed immuno-virological discordance. Overall mortality rate among PLHIV was 3.6%. Mortality rate in immuno-virological concordant group was 2.8%. Of immuno-virological discordant population, 505 (26.3%) were virological only responders (VO) with 5.35% mortality rate & 33 (1.7%) were immunological only responders (IO) with 9.09% mortality rate. High number of immunological discordant patients in the present study warrants the further evaluation of these patients with change in appropriate treatment strategy to decrease the mortality among this group.

CONCLUSION

This study emphasizes the role of immunological monitoring as well as virological monitoring to improve the life expectancy of PLHIV.

PSGL-1, a Strategic Biomarker for Pathological Conditions in HIV Infection: A Hypothesis Review

P-selectin glycoprotein ligand-1 (PSGL-1) has been established to be a cell adhesion molecule that is involved in the cellular rolling mechanism and the extravasation cascade, enabling the recruitment of immune cells to sites of inflammation. In recent years, researchers have established that PSGL-1 also functions as an HIV restriction factor. PSGL-1 has been shown to inhibit the HIV reverse transcription process and inhibit the infectivity of HIV virions produced by cells expressing PSGL-1. Cumulative evidence gleaned from contemporary literature suggests that PSGL-1 expression negatively affects the functions of immune cells, particularly T-cells, which are critical participants in the defense against HIV infection. Indeed, some researchers have observed that PSGL-1 expression and signaling provokes T-cell exhaustion. Additionally, it has been established that PSGL-1 may also mediate virus capture and subsequent transfer to permissive cells. We therefore believe that, in addition to its beneficial roles, such as its function as a proinflammatory molecule and an HIV restriction factor, PSGL-1 expression during HIV infection may be disadvantageous and may potentially predict HIV disease progression. In this hypothesis review, we provide substantial discussions with respect to the possibility of using PSGL-1 to predict the potential development of particular pathological conditions commonly seen during HIV infection. Specifically, we speculate that PSGL-1 may possibly be a reliable biomarker for immunological status, inflammation/translocation, cell exhaustion, and the development of HIV-related cancers. Future investigations directed towards our hypotheses may help to evolve innovative strategies for the monitoring and/or treatment of HIV-infected individuals.

Effects of anti-retroviral therapy on baseline serum interleukin-18 levels in HIV-I infected patients relative to viral suppression and CD4+ gain: A prospective pilot study

Background

In HIV infection, dysregulation of cytokines, including interleukin 18 (IL-18), has been linked to poor clinical outcomes in studies mainly conducted in resource-rich countries. This phenomenon has not been well-studied in resource-limited settings where outcomes could be confounded by exposure to endemic infections and genetic factors.

Objectives

Therefore, the influence of immunological and virological status of HIV-infected, antiretroviral therapy (ART)-naïve patients on serum IL-18 levels at baseline (pretreatment) and 24 weeks following initiation of combination ART (cART24) in a resource-limited setting was investigated.

Methods

Using the cross-sectional and longitudinal mixed method design, a total of Forty-four (44) newly diagnosed consenting HIV patients were consecutively recruited during routine clinic visits at the Nasara Treatment & Care Centre of the Ahmadu Bello University Teaching Hospital (ABUTH), Zaria, Nigeria between December 2016 to January 2018, and followed up for 24 weeks on initiation of first-line cART.

Results

Serum IL-18 concentrations, CD4+ T-cell counts (CD4+) counts, and HIV1 RNA levels were determined at baseline and cART24. There was little CD4+ count gain in both <200 and ≥ 200 cell/mm3subgroups despite the high proportion of subjects having virological suppression (n = 35, [80%]) at cART24. However, at cART24 there was a more than a threefold decrease in the level of IL-18 concentration compared to baseline in patients with <200 cells/mm3 and a significant decrease in the median plasma IL-18 concentration in patients with HIV1 RNA <1000 cp/mL at cART24. A multivariate logistic regression model shows IL-18 intermediate quartile to be more related to immunological poor gain as compared to the highest quartile.

Conclusion

Our study found high baseline and significantly low levels of IL-18 at cART24 in virologically suppressed subjects but not among virological non-suppressed responders despite comparable IL-18 levels by CD4+ T cell count strata at cART24. These findings have implications for risk stratification and treatment outcomes in HIV-positive persons.

Humoral and cellular immunity to SARS-COV-2 after vaccination with mRNA vaccines in PLWH with discordant immune response. Influence of the vaccine administered

Background

Data on SARS-CoV-2 mRNA vaccine immunogenicity in people living with human immunodeficiency virus (PLWH) and discordant immune response (DIR) are currently limited. Therefore, we compare the immunogenicity of these vaccines in DIR and immunological responders (IR).

Methods

A prospective cohort that enrolled 89 participants. Finally, 22 IR and 24 DIR were analyzed before vaccination (T0), one (T1) and six months (T2) after receiving BNT162b2 or mRNA-1273 vaccine. Additionally, 10 IR and 16 DIR were evaluated after a third dose (T3). Anti-S-RBD IgG, neutralizing antibodies (nAb), neutralization activity, and specific memory B cells were quantified. Furthermore, specific CD4+ and CD8+ responses were determined by intracellular cytokine staining and polyfunctionality indexes (Pindex).

Results

At T1, all participants developed anti-S-RBD. 100% IR developed nAb compared to 83.3% DIR. Spike-specific B cells were detected in all IR and 21/24 DIR. Memory CD4+ T cells responded in 5/9 IR and 7/9 DIR, mainly based on the expression of IFN-γ and TNF-α, with a higher Pindex in DIR. Memory CD8+ T cells responded in only four participants in each group. At T2, anti-S-RBD and nAb titers were higher in DIR than in IR. In both groups, there was an increase in specific B memory cells, higher in DIR. Six IR and five DIR maintained a specific memory CD4+ response. Memory CD8+ response was preserved in IR but was lost in DIR. In a multivariate linear regression analysis, receiving mRNA-1273 instead of BNT162b2 played a prominent role in the results.

Conclusions

Our data suggest that PLWH with DIR can mount an immune response similar to those with higher CD4+, provided they receive the mRNA-1273 vaccine instead of others less immunogenic.

Enteropathy and gut dysbiosis as obstacles to achieve immune recovery in undetectable people with HIV: a clinical view of evidence, successes, and projections

Immune performance following antiretroviral therapy initiation varies among patients. Despite achieving viral undetectability, a subgroup of patients fails to restore CD4+ T-cell counts during follow-up, which exposes them to non-AIDS defining comorbidities and increased mortality. Unfortunately, its mechanisms are incompletely understood, and no specific treatment is available. In this review, we address some of the pathophysiological aspects of the poor immune response from a translational perspective, with emphasis in the interaction between gut microbiome, intestinal epithelial dysfunction, and immune system, and we also discuss some studies attempting to improve immune performance by intervening in this vicious cycle.

Immunovirological discordance among people living with human immunodeficiency virus at a center in Western India: A retrospective study

Background and Objectives

Treatment of people living with human immunodeficiency virus (HIV) (PLHIV) is monitored using plasma HIV viral load levels and CD4 counts. Patients with either immunological nonresponse (virological suppression achieved) or virological nonresponse (immune reconstitution achieved) are termed as having a discordant response. These patients are at higher risk for acquired immunodeficiency syndrome (AIDS)-related infections/diseases/neoplasms, non-AIDS-related illnesses (cardiovascular, neurological, renal, hepatic diseases), and all-cause death. This study was conducted to assess the prevalence of immunovirological discordance among PLHIV after completion of at least 1 year of combination antiretroviral therapy (cART) at an antiretroviral therapy (ART) plus center in India and analyze contributory factors.

Methods

The study was a retrospective study of PLHIV receiving cART at the ART plus clinic in Western India from January 18 to December 21. Four hundred and ninety-six patients were studied based on sample size calculated and assessed for CD4 and viral load response at 0, 6, and 12 months of ART.

Results

Of the 496 patients, 48 patients (9.7%) had immunovirological discordance. Out of them, 36 patients (75%) had a virological response (immunological nonresponse) and 12 (25%) patients had an immunological response (virological nonresponse). The factors contributing to immunological nonresponse were as follows - low baseline CD4 levels (<100 cells) (36.1%), adherence <95% (33.3%), presence of opportunistic infections (16.6%), and failure on first-line therapy (11.1%). Other factors noted included higher baseline viral load (2.7%), chronic kidney disease (5.5%), and chronic hepatitis B virus co-infection (5.5%). Virological nonresponse was associated with poor adherence to therapy <95% (33%) and failure of first-line regimen (33%). Opportunistic infections were noted among 33% of patients and 8.3% of patients were found to have higher baseline viral load.

Interpretation and Conclusion

Immunovirological discordance is an important factor influencing response to cART and is associated with many complications such as AIDS and non-AIDS-related events and even death. Improved adherence and timely identification and management of opportunistic infections are measures that are beneficial in reducing the incidence of immunovirological discordance.

Immune-Related Gene Profile in HIV-Infected Patients with Discordant Immune Response

Background

Background: In spite of many reports on persistent low CD4 T cell counts and change in immune-related gene expression level in patients with HIV infection, there is still uncertainty about significant association between gene expression level and HIV infection in patients with and without discordant immune response (DIR). The aim of this study was to compare the expression level of CD4, CCL5, IFN-γ, STAT1, APOBEC3G, CD45, and ICAM-1 genes in HIV-1-positive patients with and without DIR.

Methods

Methods: In this study, 30 HIV-1-positive patients (15 patients with and 15 patients without DIR [control group]) were included. PBMCs of the patients were collected through density radient centrifugation with Ficoll-Hypaque. RNeasy Plus Mini kit was used to extract RNA. Relative expression levels of CD4, CCL5, IFN-γ, STAT1, APOBEC3G, CD45, and ICAM-1 genes were evaluated by real-time PCR. The data were analyzed using one-way ANOVA.

Results

Results: CD4 T cell counts were significantly lower in DIR patients than the control group (p < 0.01). While there was no significant difference in the relative expression levels of CD4, CCL5, IFN-γ, STAT1, CD45, and ICAM-1 between patients with DIR and control group, APOBEC3G expression level was significantly higher in the patients with DIR as compare to the control group (p < 0.01).

Conclusion

Conclusion: Our findings suggest a significantly higher APOBEC3G expression level in patients with DIR, suggesting the potential role of APOBEC3G in patients with immunological discordance besides its suppressing role in HIV-1 infection. Confirmation of this hypothesis requires further research.

Anti-CD4 autoantibodies in immunological non-responder people living with HIV: Cause of CD4+ T-cell depletion?

OBJECTIVE

We aimed to evaluate the anti-CD4 IgG role in the poor immune recovery of immunological nonresponder people with HIV (INR).

DESIGN

INR display low CD4+ T-cell increase despite long-term undetectable viremia. Among other factors, autologous anti-CD4 IgG-dependent cellular cytotoxicity (ADCC) by natural killer (NK) cells has been proposed to cause CD4+ T-cell depletion.

METHODS

Plasma anti-CD4 IgG levels were quantified and purified by chromatography columns for the subsequent use in a coculture of CD4+ T and NK cells. We analyzed NK cell degranulation markers (CD107a, perforin and granzyme B) and IFN-γ release, and CD4+ T-cell death. Binding affinity of anti-CD4 IgG for CD4+ T cells was also assessed.

RESULTS

A total of 168 individuals were enrolled (INR, 56; immunological responders, 40; treatment-naive, 39; and healthy controls, 33). The highest anti-CD4 IgG levels were found in treatment-naive PWH, followed by participants on treatment. There were no correlations between anti-CD4 IgG levels and CD4+ T-cell counts. In a 15-participant subgroup (naive, immunological responders, and INR), anti-CD4 IgG induced a slight NK-cell expression of degranulation markers and IFN-γ; however, the percentage of CD4+ T-cell death was negligible. Consistently, no significant changes in NK cell polyfunctionality were observed. In addition, purified anti-CD4 IgG showed scarce binding affinity for CD4+ T cells. These results were similar in all analyzed participant groups.

CONCLUSION

Our results suggest that autologous anti-CD4 IgG neither trigger CD4+ T-cell death by ADCC nor are responsible for CD4+ lymphocyte depletion in INR.

VIDEO ABSTRACT

http://links.lww.com/QAD/C518.

Clinical effects of durability of immunosuppression in virologically suppressed ART-initiating persons with HIV in Latin America. A retrospective cohort study

Background

Clinical outcomes are rarely studied in virologically suppressed people living with HIV (PWH) and incomplete CD4 recovery. To explore whether time living with severe immunosuppression predict clinical outcomes better than baseline or time updated CD4, we estimated the association between cumulative percentage of time with CD4 <200 cells/μL during viral suppression (VS) (%tCD4<200), and mortality and comorbidities during 2000-2019.

Methods

In a retrospective cohort analysis, we followed PWH initiating ART in Latin America from first VS (HIV-RNA<200 copies/μL) to death, virological failure or loss to follow-up. We fit Cox models to estimate risk of death and/or AIDS-defining and serious non-AIDS-defining events (ADE and SNADE -cancer, cardiovascular, liver, and renal diseases) by %tCD4<200 (continuous variable). We predicted survival probabilities for each event and calculated risks of hypothetical cases of different %tCD4<200.

Findings

In 8,369 patients with 34·9 months of follow-up (median, IQR: 16·7, 69·1), 4,274 (51%) started ART with CD4<200 cells/μL. Median %tCD4<200 was 0% (IQR: 0, 15%). We identified 195 (2·3%) deaths and 584 (7·2%) patients with ADE/SNADE. For an increased %tCD4<200 of 15% (e.g., 15% vs. 0%), the adjusted relative hazard (aHR) of death was 1·27 (95% confidence interval [CI]: 1·19 - 1·35), of ADE/SNADE was 1·13 (95%CI: 1·09 - 1·17), of SNADE was 0·96 (95%CI: 0·89 - 1·02) and of death/ADE/SNADE was 1·11 (95%CI: 1·07 - 1·14). Estimates were similar after adjusting for time updated CD4 count.

Interpretation

In virologically suppressed PWH, increased time living with severe immunosuppression had an increased risk of death and ADE/SNADE in this Latin American cohort, independently of time updated CD4 count.

Funding

This work was supported by the NIH-funded Caribbean, Central and South America network for HIV epidemiology (CCASAnet, U01AI069923), a member cohort of the International Epidemiologic Databases to Evaluate AIDS (leDEA). This award is funded by the following institutes: Eunice Kennedy Shriver National Institute Of Child Health & Human Development (NICHD), National Cancer Institute (NCI), National Institute Of Allergy And Infectious Diseases (NIAID), National Institute Of Mental Health (NIMH), the National Heart, Lung, and Blood Institute (NHLBI), the National Institute on Alcohol Abuse and Alcoholism (NIAAA), the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), and the Fogarty International Center (FIC). Specific funding was provided from the Fogarty International Center (FIC) for lead author, Yanink Caro-Vega, for the Fogarty-IeDEA Mentorship Program (FIMP).

Immunovirological discordance among female sex workers who start antiretroviral therapy in Burkina Faso

Background

In people living with HIV/AIDS (PLWHA), initiation of antiretroviral therapy (ART) leads to sustained effective suppression of viral replication and increasing CD4 + T cell count. However, a fraction of ART-treated patients still fail to reach adequate CD4 + T cell number despite a suppressed viral load (VL), and this phenomenon is defined as immunovirological discordance (IVD). In Africa, several studies have reported immunovirological outcomes of antiretroviral therapy, but little is known about IVD occurrence in Female sex workers (FSW). This study aimed to assess the prevalence of IVD and associated factors among a cohort of HIV infected FSW in Burkina Faso.

Methods

We conducted a cohort study from December 2003 to October 2016. Immunovirological discordance was defined as CD4 + T cell gain < 100 cells/µL despite a suppressed VL (VL < 1000 copies/mL) 12 months after ART initiation. The CD4 + T cells were counted using BD FACSCount™ System and point of care Pima™ CD4 + Analyzer. HIV-1 RNA was quantified by real-time polymerase-chain-reaction assay with the use of the ABI 7000 system. We conducted a logistic regression to identify factors associated with discordant responses.

Results

Among the 123 HIV-1 infected FSW having at least 12 months follow-up on ART, 105 (85.4%) achieved HIV-1 RNA suppression. Among the latter 25 gained less than 100 CD4 + T cells within 12 months follow-up. The IVD rate was 23.8% (95%CI 16.04%–33.11%). After adjustment for age, WHO clinical stage and ART regimen including nucleoside/nucleotide reverse transcriptase inhibitors, only baseline CD4 + T cell count between 200 to 350 cells/µL (adjusted OR: 4.15; 95%CI 1.13–15.22) and 350 to 500 cells/µL (adjusted OR: 17.50; 95%CI 2.68–114.31) remain significantly associated with IVD occurrence.

Conclusions

Immunovirological discordance response was common in FSW with proportions close to those observed in the general population. A diagnosis and personalized follow-up of patients who do not achieve full immune reconstitution would make it possible to avoid complications in terms of morbidity and mortality.

Clinical factors and outcomes associated with immune non-response among virally suppressed adults with HIV from Africa and the United States

A significant minority of people living with HIV (PLWH) achieve viral suppression (VS) on antiretroviral therapy (ART) but do not regain healthy CD4 counts. Clinical factors affecting this immune non-response (INR) and its effect on incident serious non-AIDS events (SNAEs) have been challenging to understand due to confounders that are difficult to control in many study settings. The U.S. Military HIV Natural History Study (NHS) and African Cohort Study (AFRICOS). PLWH with sustained VS (< 400 copies/ml for at least two years) were evaluated for INR (CD4 < 350 cells/µl at the time of sustained VS). Logistic regression estimated adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for factors associated with INR. Cox proportional hazards regression produced adjusted hazard ratios (aHRs) for factors associated with incident SNAE after sustained VS. INR prevalence was 10.8% and 25.8% in NHS and AFRICOS, respectively. Higher CD4 nadir was associated with decreased odds of INR (aOR = 0.34 [95% CI 0.29, 0.40] and aOR = 0.48 [95% CI 0.40, 0.57] per 100 cells/µl in NHS and AFRICOS, respectively). After adjustment, INR was associated with a 61% increase in relative risk of SNAE [95% CI 1.12, 2.33]. Probability of "SNAE-free" survival at 15 years since sustained VS was approximately 20% lower comparing those with and without INR; nearly equal to the differences observed by 15-year age groups. CD4 monitoring before and after VS is achieved can help identify PLWH at risk for INR. INR may be a useful clinical indicator of future risk for SNAEs.

So Pathogenic or So What?-A Brief Overview of SIV Pathogenesis with an Emphasis on Cure Research

HIV infection requires lifelong antiretroviral therapy (ART) to control disease progression. Although ART has greatly extended the life expectancy of persons living with HIV (PWH), PWH nonetheless suffer from an increase in AIDS-related and non-AIDS related comorbidities resulting from HIV pathogenesis. Thus, an HIV cure is imperative to improve the quality of life of PWH. In this review, we discuss the origins of various SIV strains utilized in cure and comorbidity research as well as their respective animal species used. We briefly detail the life cycle of HIV and describe the pathogenesis of HIV/SIV and the integral role of chronic immune activation and inflammation on disease progression and comorbidities, with comparisons between pathogenic infections and nonpathogenic infections that occur in natural hosts of SIVs. We further discuss the various HIV cure strategies being explored with an emphasis on immunological therapies and "shock and kill".

Neighbourhood-level material deprivation and response to combination antiretroviral therapy in the Canadian Observational Cohort (CANOC): a longitudinal cohort study

BACKGROUND

Socioeconomic status has been associated with higher viral loads and lower CD4 cell counts among people living with HIV. The objective of this study was to evaluate the relation between neighbourhood-level material deprivation and immunologic and virologic response to combination antiretroviral therapy (ART) among people living with HIV in Canada.

METHODS

The Canadian Observational Cohort (CANOC) is a longitudinal cohort of people living with HIV, containing data from 2000-2016 from 5 Canadian provinces. We defined response to combination ART as positive if the CD4 cell count increased by 50 cells/mm³ (0.05 cells × 10⁹/L) or more (CD4+) and viral load decreased to 50 copies/mL or less (VL+) within 6 months of treatment initiation. We further categorized response to therapy as concordant positive (CD4+/VL+), concordant negative (CD4-/VL-) or discordant (CD4+/VL- or CD4-/VL+). We used adjusted multinomial logistic regression to quantify the relation between neighbourhood-level material deprivation and immunologic and virologic response.

RESULTS

This study included 8274 people living with HIV, of which 1754 (21.2%) lived in the most materially deprived neighbourhoods. Most individuals (62.2%) showed a concordant positive response to combination ART. After adjustment, living in the most materially deprived neighbourhoods was associated with a CD4-/VL+ discordant response (adjusted odds ratio [OR] 1.31, 95% confidence interval [CI] 1.06-1.62) and a concordant negative response (adjusted OR 1.45, 95% CI 1.13-1.86), using a concordant positive response as the reference. No other deprivation quartile was independently associated with a particular response.

INTERPRETATION

People living with HIV from the most materially deprived neighbourhoods had increased odds of poor immunologic or virologic response to combination ART. These results motivate further study of the specific socioeconomic factors that potentially affect response to combination ART among people living with HIV in Canada.

Immunological factors associated with discordant virological response postcombination antiretroviral therapy in pediatric human immunodeficiency virus infection

OBJECTIVES

Evaluation of immunological factors responsible for discordant virological responses postcombination antiretroviral therapy (cART) in human immunodeficiency virus (HIV)-positive children aged <5 years.

MATERIALS AND METHODS

Immunological profiling of enrolled 30 HIV-positive children was done at enrollment, 6 and 12 months. Flow cytometric analysis was performed for enumeration of counts and percentage of CD4⁺, CD8⁺, and CD19⁺ cells; expression of CD19, CD86, PD-1, CD3, CD8 and CD28 on lymphocytes was evaluated using whole blood staining technique with monoclonal antibodies. HIV-1 viral load was quantified using a real-time polymerase chain reaction. Serum levels of immunoglobulin G (IgG), immunoglobulin A (IgA), immunoglobulin (IgM), and interleukin (IL)-7 were quantitated using quantitative enzyme-linked immunosorbent assay kits. The HIV-infected children were categorized into virological responders (VRs; HIV-1 plasma viral load <47 copies/mL) and virological nonresponders (VNRs; HIV-1 plasma viral load >1000 copies/mL) following 1-year cART.

RESULTS

The frequency of CD28⁺ CTLs cells was higher (P < 0.0001), and the frequency of CD28-CTLs cells was lower (P < 0.0001) in VRs than VNRs. CD28⁺ and CD28-CTLs cells correlated with HIV-1 plasma viremia (r = -0.4695, P = 0.01; r = 0.40, P = 0.03, respectively). VRs had higher CD19 percentage (P = 0.04) and count (P = 0.01) than VNRs. CD19⁺ B cells in the VRs had lower expression of CD86 (P = 0.03) and PD-1 (P = 0.002) than VNRs. VR had lower levels of serum IgG (P = 0.03), IgM (P = 0.04), and IL-7 (P = 0.01) than VNRs.

CONCLUSIONS

High baseline B-cell counts, lower serum IgG, IgM, IL-7 levels, lower activation and exhaustion of B cells, and higher frequency of CD28⁺ CTLs are associated with positive virological response, whereas elevated CD28-CTLs are associated with the poor virological outcomes in HIV-infected children.

Immune recovery after antiretroviral therapy initiation: a challenge for people living with HIV in Brazil

Immune recovery reflects health conditions. Our goal was to estimate the time it takes to achieve immune recovery and its associated factors, in people living with HIV (PLHIV), after antiretroviral therapy (ART) initiation. A historical cohort study was performed among PLHIV (> 18 years-old) in Minas Gerais State, Brazil, using data from healthcare databases. Patients initiating ART between 2009-2018, with T-CD4+ lymphocytes and viral load recorded before and after antiretroviral therapy were included. The outcome is achievement of immune recovery, defined as the first T-CD4+ > 500 cells/µL after ART initiation. Explanatory variables were age, gender, place of residence, year of ART initiation, baseline viral load and T-CD4+, viral load status, and adherence to ART at follow-up. Descriptive analysis, cumulative, and person-time incidences of immune recovery were estimated. Median-time to immune recovery was estimated using Kaplan-Meier method. Factors associated with immune recovery were assessed by Cox regression. Among 26,430 PLHIV, 8,014 (30%) were eligible. Most were male (67%), mean age 38.7 years, resided in non-central region, median-baseline T-CD4+ = 228 cells/µL (< 200 cells/µL = 43%) and viral load median-baseline = 4.7 log10 copies/mL (detectable viral load = 99%). Follow-up time = 15,872 person-years. Cumulative and incidence rate were 58% (95%CI: 57-58) (n = 4,678) and 29.47 cases/100 person-years, respectively. Median-time to immune recovery was of 22.8 months (95%CI: 21.9-24.0). Women living with HIV, younger than 38 years of age, with T-CD4+ baseline > 200 cells/µL, detectable viral load (baseline), antiretroviral therapy-adherence and undetectable viral load (follow-up) were independently associated with immune recovery. Time to immune recovery remains long and depends on early treatment and antiretroviral therapy-adherence.

Tobacco smoking and HIV-related immunologic and virologic response among individuals of the Canadian HIV Observational Cohort (CANOC)

We assessed the relationship between tobacco smoking and immunologic and virologic response among people living with HIV (PLWH) initiating combination antiretroviral therapy (cART) in the Canadian HIV Observational Cohort (CANOC). Positive immunologic and virologic response, respectively, were defined as ≥50 cells/mm³ CD4 count increase (CD4+) and viral suppression ≤50 copies/mL (VL+) within 6 months of cART initiation. Using multinomial regression, we examined the relationship between smoking, immunologic, and virologic response category. Model A adjusted for birth sex, baseline age, enrolling province, and era of cohort entry; models B and C further adjusted for neighbourhood level material deprivation and history of injection drug use (IDU), respectively. Among 4267 individuals (32.7%) with smoking status data, concordant positive (CD4+/VL+) response was achieved by 64.2% never, 66.9% former, and 59.4% current smokers. In the unadjusted analysis, current smoking was significantly associated with concordant negative response (odds ratio [OR] 1.85, 95% confidence interval [CI] 1.40-2.45). Similarly, models A and B showed an increased odds of concordant negative response in current smokers (adjusted OR [aOR] 1.78, 95% CI 1.32-2.39 and 1.74, 95% CI 1.29-2.34, respectively). The association between current smoking and concordant negative response was no longer significant in model C (aOR 1.18, 95%CI 0.85-1.65).

Inflammatory Phenotypes Predict Changes in Arterial Stiffness Following Antiretroviral Therapy Initiation

BACKGROUND

Inflammation drives vascular dysfunction in HIV, but in low-income settings causes of inflammation are multiple, and include infectious and environmental factors. We hypothesized that patients with advanced immunosuppression could be stratified into inflammatory phenotypes that predicted changes in vascular dysfunction on ART.

METHODS

We recruited Malawian adults with CD4 <100 cells/μL 2 weeks after starting ART in the REALITY trial (NCT01825031). Carotid femoral pulse-wave velocity (cfPWV) measured arterial stiffness 2, 12, 24, and 42 weeks post-ART initiation. Plasma inflammation markers were measured by electrochemiluminescence at weeks 2 and 42. Hierarchical clustering on principal components identified inflammatory clusters.

RESULTS

211 participants with HIV grouped into 3 inflammatory clusters representing 51 (24%; cluster-1), 153 (73%; cluster-2), and 7 (3%; cluster-3) individuals. Cluster-1 showed markedly higher CD4 and CD8 T-cell expression of HLADR and PD-1 versus cluster-2 and cluster-3 (all P < .0001). Although small, cluster-3 had significantly higher levels of cytokines reflecting inflammation (IL-6, IFN-γ, IP-10, IL-1RA, IL-10), chemotaxis (IL-8), systemic and vascular inflammation (CRP, ICAM-1, VCAM-1), and SAA (all P < .001). In mixed-effects models, cfPWV changes over time were similar for cluster-2 versus cluster-1 (relative fold-change, 0.99; 95% CI, .86-1.14; P = .91), but greater in cluster-3 versus cluster-1 (relative fold-change, 1.45; 95% CI, 1.01-2.09; P = .045).

CONCLUSIONS

Two inflammatory clusters were identified: one defined by high T-cell PD-1 expression and another by a hyperinflamed profile and increases in cfPWV on ART. Further clinical characterization of inflammatory phenotypes could help target vascular dysfunction interventions to those at highest risk.

CLINICAL TRIALS NETWORK

NCT01825031.

Impact of Advanced HIV Disease on Quality of Life and Mortality in the Era of Combined Antiretroviral Treatment

Currently, AIDS or severe immunodeficiency remains as a challenge for people with HIV (PWHIV) and healthcare providers. Our purpose was to analyze the impact of advanced HIV disease (AHD) on mortality, life expectancy and health-related quality of life (HRQoL). We reviewed cohort studies and meta-analyses conducted in middle- and high-income countries. To analyze HRQoL, we selected studies that reported overall health and/or physical/mental health scores on a validated HRQoL instrument. AIDS diagnosis supposes a higher risk of mortality during the first six months, remaining higher for 48 months. It has been reported that cancer and cardiovascular disease persist as frequent causes of mortality in PWHIV, especially those with previous or current AHD. PWHIV who initiate combination antiretroviral therapy (cART) with CD4 < 200 cells/µL have significantly lower estimated life expectancy than those with higher counts. AHD is associated with lower HRQoL, and a worse physical health or mental health status. AIDS and non-AIDS defining events are significant predictors of a lower HRQoL, especially physical health status. AHD survivors are in risk of mortality and serious comorbidities, needing special clinical attention and preventive programs for associated comorbidities. Their specific needs should be reflected in HIV guidelines.

Role and effects of zinc supplementation in HIV-infected patients with immunovirological discordance: A randomized, double blind, case control study

Introduction

It has been estimated that between 15% and 18% of patients who start antiretroviral therapy (ART) do not achieve a successful immune recovery despite complete virological suppression. In the literature this phenomenom is known as poor immune recovery or immunovirological discordance (IVD). Zinc has an immunomodulatory role associated with T lymphocytes and its supplementation could enhance immune recovery.

Objective

To determine if zinc supplementation on IVD patients prevents immune failure after 12 months of supplementation. Secondary objectives were to determine serum zinc levels in HIV patients with and without IVD and the frequency of hypozincemia in discordant patients.

Method

We reviewed the historical record of patients under care at Arriarán Foundation. Following inclusion criteria were defined: 1) age ≥ 18 years, 2) standard ART (three effective drugs) for at least 18 months, 3) virologically suppressed for 12 months, 3) persistence of CD4 count ≤200 cells/mm³ and/or increase ≤ 80 cells/mm³ after one year of viral undetectability. A control group was assigned paired 1:1 by sex, age (± 2 years) that did achieved an increase of CD4> 350 cells/ mm³. In both groups plasma zinc levels were determined. In a later phase, patients with IVD were randomized to receive zinc (15 mg daily) versus placebo. Patients were followed for 12 months with CD4 count, viral load and zinc levels determinations every 4–6 months.

Results

A total of 80 patients, 40 patients with IVD criteria and 40 controls were included. 92.5% were men, and age average was 47.5 years. The median baseline CD4 was 189 cells/mm³ (71–258) in the cases vs. 552.5 cells/ mm³ (317–400) in the control group with a median increase at the end of the study of 39 cell/mm³ and 19 cell/mm³ respectively. There was no difference in baseline plasma zinc levels between both groups (81.7 + 18.1 in cases versus 86.2 + 11.0 in controls). In the 40 patients with IVD, the median absolute increase in CD4 after annual zinc supplementation was 31.5 cells/mm³ in the treated group versus 50 cells/mm³ in the placebo group, this difference being statistically not significant (p = 0.382).

Conclusions

Patients with IVD have plasma zinc levels similar to those who achieve adequate immune recovery. Zinc supplementation in IVD patients showed a statistically non-significant difference in in CD4 levels between cases and controls. The results warrant a comparative study with a larger number of patients.

Prevalence and Clinical Outcomes of Poor Immune Response Despite Virologically Suppressive Antiretroviral Therapy Among Children and Adolescents With Human Immunodeficiency Virus in Europe and Thailand: Cohort Study

BACKGROUND

In human immunodeficiency virus (HIV)-positive adults, low CD4 cell counts despite fully suppressed HIV-1 RNA on antiretroviral therapy (ART) have been associated with increased risk of morbidity and mortality. We assessed the prevalence and outcomes of poor immune response (PIR) in children receiving suppressive ART.

METHODS

Sixteen cohorts from the European Pregnancy and Paediatric HIV Cohort Collaboration (EPPICC) contributed data. Children <18 years at ART initiation, with sustained viral suppression (VS) (≤400 copies/mL) for ≥1 year were included. The prevalence of PIR (defined as World Health Organization advanced/severe immunosuppression for age) at 1 year of VS was described. Factors associated with PIR were assessed using logistic regression. Rates of acquired immunodeficiency syndrome (AIDS) or death on suppressive ART were calculated by PIR status.

RESULTS

Of 2318 children included, median age was 6.4 years and 68% had advanced/severe immunosuppression at ART initiation. At 1 year of VS, 12% had PIR. In multivariable analysis, PIR was associated with older age and worse immunological stage at ART start, hepatitis B coinfection, and residing in Thailand (all P ≤ .03). Rates of AIDS/death (95% confidence interval) per 100 000 person-years were 1052 (547, 2022) among PIR versus 261 (166, 409) among immune responders; rate ratio of 4.04 (1.83, 8.92; P < .001).

CONCLUSIONS

One in eight children in our cohort experienced PIR despite sustained VS. While the overall rate of AIDS/death was low, children with PIR had a 4-fold increase in risk of event as compared with immune responders.

Mesenchymal stromal cells in human immunodeficiency virus-infected patients with discordant immune response: Early results of a phase I/II clinical trial

Between 15% and 30% of HIV‐infected subjects fail to increase their CD4⁺ T‐cell counts despite continuous viral suppression (immunological nonresponders [INRs]). These subjects have a higher morbidity and mortality rate, but there are no effective treatments to reverse this situation so far. This study used data from an interrupted phase I/II clinical trial to evaluate safety and immune recovery after INRs were given four infusions, at baseline and at weeks 4, 8, and 20, with human allogeneic mesenchymal stromal cells from adipose tissue (Ad‐MSCs). Based on the study design, the first 5 out of 15 INRs recruited received unblinded Ad‐MSC infusions. They had a median CD4⁺ nadir count of 16/μL (range, 2‐180) and CD4⁺ count of 253 cells per microliter (171‐412) at baseline after 109 (54‐237) months on antiretroviral treatment and 69 (52‐91) months of continuous undetectable plasma HIV‐RNA. After a year of follow‐up, an independent committee recommended the suspension of the study because no increase of CD4⁺ T‐cell counts or CD4⁺/CD8⁺ ratios was observed. There were also no significant changes in the phenotype of different immunological lymphocyte subsets, percentages of natural killer cells, regulatory T cells, and dendritic cells, the inflammatory parameters analyzed, and cellular associated HIV‐DNA in peripheral blood mononuclear cells. Furthermore, three subjects suffered venous thrombosis events directly related to the Ad‐MSC infusions in the arms where the infusions were performed. Although the current study is based on a small sample of participants, the findings suggest that allogeneic Ad‐MSC infusions are not effective to improve immune recovery in INR patients or to reduce immune activation or inflammation. ClinicalTrials.gov identifier: NCT0229004. EudraCT number: 2014‐000307‐26.

HIV-infected immunological non-responders have colon-restricted gut mucosal immune dysfunction

Background

Human immunodeficiency virus (HIV)–infected immunological nonresponders (INRs) fail to reconstitute their CD4⁺ T-cell pool after initiation of antiretroviral therapy, and their prognosis is inferior to that of immunological responders (IRs). A prevailing hypothesis is that the INR phenotype is caused by a persistently disrupted mucosal barrier, but assessments of gut mucosal immunology in different anatomical compartments are scarce.

Methods

We investigated circulating markers of mucosal dysfunction, immune activation, mucosal Th17 and Th22 cells, and mucosa-adherent microbiota signatures in gut mucosal specimens from sigmoid colon and terminal ileum of 19 INRs and 20 IRs in addition to 20 HIV-negative individuals.

Results

INRs had higher blood levels of the enterocyte damage marker intestinal fatty acid–binding protein than IRs. In gut mucosal biopsies, INRs had lower fractions of CD4⁺ T cells, higher fractions of interleukin 22, and a tendency to higher fractions of interleukin 17–producing CD4⁺ T cells. These findings were all restricted to the colon and correlated to circulating markers of enterocyte damage. There were no observed differences in gut microbial composition between INRs and IRs.

Conclusions

Restricted to the colon, enterocyte damage and mucosal immune dysfunction play a role for insufficient immune reconstitution in HIV infection independent of the gut microbiota.

Negative Diagnostic PCR Tests in School-Aged, HIV-Infected Children on Antiretroviral Therapy Since Early Life in Johannesburg, South Africa

BACKGROUND

Younger age at antiretroviral therapy (ART) initiation has been associated with smaller HIV reservoirs. We investigated whether younger age of ART initiation is associated with testing negative and weaker signal on a standard HIV diagnostic test in treated children.

METHODS

At exit from a longitudinal study at 2 sites in Johannesburg, South Africa, 316 school-aged, HIV-infected children on continuous ART started at a median age of 6.3 months, were tested with standard total nucleic acid PCR used for infant diagnosis. All negative results were repeated. Simultaneous viral load (VL) and CD4 T-cell counts/percentages, along with data collected over the prior 4 years, were used in multivariable regression to predict negative PCR results and higher cycle threshold (Ct) values (weaker signal).

RESULTS

Seven children (2.2%, 95% confidence interval: 0.6 to 3.8) in the full cohort had negative PCR results; all 7 were in a subset of 102 (6.9%, 95% confidence interval: 2.0 to 11.8) who had initiated ART at age 0-4 months and had VL <50 copies/mL at the time of PCR testing. Only one repeat tested as negative. Younger age at ART initiation, VL <50 copies/mL at time of test, sustained VL <400 copies/mL, lower CD4 T-cell counts, and ever treated with efavirenz were significant predictors of weaker signal on the diagnostic test.

CONCLUSIONS

In a small proportion of children who start ART in the first months of life and remain on continuous therapy, standard diagnostic HIV PCR tests may result as negative. Repeat testing may resolve uncertainty of diagnosis.

Immunological status and virological suppression among HIV-infected adults on highly active antiretroviral therapy

BACKGROUND

World Health Organization (WHO) recommends that viral load ([VL) is a primary tool that clinicians and researchers have used to monitor patients on antiretroviral therapy (ART), an antiviral drug against retroviruses. Whereas, CD4 cell counts can only be used to monitor clinical response to ART in the absence of VL testing service. Therefore, this study is aimed to assess the level of immunological status and virological suppression, and identify associated factors among human immunodeficiency virus ([HIV)-infected adults who were taking antiretroviral drugs of combination regimen know as highly active antiretroviral therapy (HAART).

METHODS

A hospital-based cross-sectional study was conducted at the University of Gondar comprehensive specialized referral hospital from February to April 2018. A total of 323 adult participants on HAART were selected using a systematic random sampling technique and enrolled into the study. Blood samples for viral load determination and CD4 cell count were collected. Binary logistic regression analysis was used to determine factors associated with immunologic status and virological suppression in HIV patients on HAART. Odds ratio with 95% CI was used to measure the strength of association.

RESULTS

Virological suppression (VL level < 1000 copies/ml) was found in 82% (95% CI 77.7, 86.1) of study participants, and it has been associated with CD4 cell count between 350 and 499 cells/mm³ (adjusted odds ratio (AOR) = 2.56; 95% CI 1.14, 5.75) and > 499 cells/mm³ (AOR = 7.71; 95% CI 3.48, 17.09) at VL testing and current age > 45 years old (AOR = 5.99; 95% CI 2.12, 16.91). Similarly, favorable immunological status (≥ 400 cells/mm³ for male and ≥ 466 cells/mm³ for female) was observed in 52.9% (95% CI 47.4, 58.8) of the study participants. Baseline CD4 cell count of > 200 cells/mm³, age at enrollment of 26 through 40 years old, and urban residence were significantly associated with favorable immunological status.

CONCLUSION

Though the majority of HIV-infected adults who were on HAART had shown viral suppression, the rate of suppression was sub-optimal according to the UNAIDS 90-90-90 target to help end the AIDS pandemic by 2020. Nonetheless, the rate of immunological recovery in the study cohort was low. Hence, early initiation of HAART should be strengthened to achieve good virological suppression and immunological recovery.

Purifying Selection in Human Immunodeficiency Virus-1 pol Gene in Perinatally Human Immunodeficiency Virus-1-Infected Children Harboring Discordant Immunological Response and Virological Nonresponse to Long-Term Antiretroviral Therapy

Background

Biological monitoring of antiretroviral treatment (ART) in human immunodeficiency virus (HIV)-infected pediatric population remains challenging. The aim of the present study was to assess the long-term HIV-1 genetic diversity in pol gene in HIV-1-infected children in virological failure under antiretroviral regimen adapted according to the successive World Health Organization (WHO) guidelines for resource-constrained settings.

Methods

HIV-1 diversity in pol gene was assessed in HIV-1-infected children and adolescents born from HIV-infected mothers (median age at follow-up: 13.8 years) in virological failure (VF⁺) despite long-term regimen recommended by the WHO. The numbers of nonsynonymous substitutions per potential nonsynonymous site (dN) and of synonymous substitutions at potential synonymous sites (dS) in HIV-1 pol gene and the dN/dS ratios were used to estimate the selective pressure on circulating HIV-1.

Results

The immunological responses to ART basically corresponded to: 1) Full therapeutic failure with immunological (I^-) and virological nonresponses in one-quarter (24.6%) of study children ((I^-, VF⁺) subgroup); 2) Discordant immunovirological responses with paradoxical high CD4 T cell counts (I⁺) and high HIV-1 RNA load in the remaining cohort patients (75.4%) ((I⁺, VF⁺) subgroup). The mean dS was 1.8-fold higher in (I⁺, VF⁺) than (I^-, VF⁺) subgroup (25.9 ± 18.4 vs. 14.3 ± 10.8). In the (I⁺, VF⁺) subgroup, the mean dS was 1.6-fold higher than the mean dN. Finally, the mean dN/dS ratio was 2.1-fold lower in (I⁺, VF⁺) than (I^-, VF⁺) subgroup (0.6 ± 0.3 vs. 1.3 ± 0.7), indicating purifying selection in the immunovirological discordant (I⁺, VF⁺) subgroup and positive selection in the immunovirological failure (I^-, VF⁺) subgroup.

Conclusions

Children and adolescents in immunovirological therapeutic failure harbor positive selection of HIV-1 strains favoring diversifying in pol-encoded amino acids. In contrast, children with persistent discordant immunovirological responses show accumulation of mutations and purifying selection in pol gene sequences, indicating limited genetic evolution and likely suggesting genetic adaptation of viruses to host functional constraints.

Definition of Immunological Nonresponse to Antiretroviral Therapy: A Systematic Review

BACKGROUND

Terms and criteria to classify people living with HIV on antiretroviral therapy who fail to achieve satisfactory CD4 T-cell counts are heterogeneous, and need revision and summarization.

METHODS

We performed a systematic review of PubMed original research articles containing a set of predefined terms, published in English between January 2009 and September 2018. The search retrieved initially 1360 studies, of which 103 were eligible. The representative terminology and criteria were extracted and analyzed.

RESULTS

Twenty-two terms and 73 criteria to define the condition were identified. The most frequent term was "immunological nonresponders" and the most frequent criterion was "CD4 T-cell count <350 cells/µL after ≥24 months of virologic suppression." Most criteria use CD4+ T-cell counts as a surrogate, either as an absolute value or as a change after a defined period of time [corrected]. Distinct values and time points were used. Only 9 of the 73 criteria were used by more than one independent research team. Herein we propose 2 criteria that could help to reach a consensus.

CONCLUSIONS

The high disparity in terms and criteria here reported precludes data aggregation and progression of the knowledge on this condition, because it renders impossible to compare data from different studies. This review will foster the discussion of terms and criteria to achieve a consensual definition.

Escalating and sustained immunovirological dissociation among antiretroviral drug-experienced perinatally human immunodeficiency virus-1-infected children and adolescents living in the Central African Republic: A STROBE-compliant study

Sub-Saharan Africa has the vast majority (∼90%) of new pediatric acquired immunodeficiency syndrome cases worldwide. Biologically monitoring HIV-infected pediatric populations remains challenging. The differential interest of human immunodeficiency virus (HIV)-1 RNA loads and CD4 T-cell counts is debated for the treatment of pediatric acquired immunodeficiency syndrome patients.Long-term antiretroviral treatment (ART) outcomes regarding immunological and virological surrogate markers were longitudinally evaluated between 2009 and 2014 (over 57 months) in 245 perinatally HIV-1-infected children and adolescents born from HIV-infected mothers, treated at inclusion for at least 6 months by the World Health Organization-recommended ART in Bangui, Central African Republic.Patients were monitored over time biologically for CD4 T-cell counts, HIV-1 RNA loads, and drug resistance mutation genotyping.Children lost to follow-up totaled 6%. Four categories of immunovirological responses to ART were observed. At baseline, therapeutic success with sustained immunological and virological responses was observed in 80 (32.6%) children; immunological and virologic nonresponses occurred in 32 (13.0%) children; finally, the majority (133; 54.2%) of the remaining children showed discordant immunovirological responses. Among them, 33 (13.4%) children showed rapid virological responses to ART with an undetectable viral load, whereas immunological responses remained absent after 6 months of treatment and increased progressively over time in most of the cases, suggesting slow immunorestoration. Notably, nearly half of the children (40.8% at baseline and 48.2% at follow-up) harbored discordant immunovirological responses with a paradoxically high CD4 T-cell count and HIV-1 RNA load, which are always associated with high levels of drug resistance mutations. The latter category showed a significant increase over time, with a growth rate of 1.23% per year of follow-up.Our STROBE-compliant study demonstrates the high heterogeneity of biological responses under ART in children with frequent passage from 1 category to another over time. Close biological evaluation with access to routine plasma HIV-1 RNA load monitoring is crucial for adapting the complex outcomes of ART in HIV-infected children born from infected mothers.

CD4 rate of increase is preferred to CD4 threshold for predicting outcomes among virologically suppressed HIV-infected adults on antiretroviral therapy

Objectives

Immune non-responders (INR) have poor CD4 recovery and are associated with increased risk of serious events despite antiretroviral therapy (ART). A clinically relevant definition for INR is lacking.

Methods

We conducted a retrospective analysis of three large cohorts: Infectious Disease Clinic at the Atlanta Veterans Affairs Medical Center, the US Military HIV Natural History Study and Infectious Disease Program of the Grady Health System in Atlanta, Georgia. Two-stage modeling and joint model (JM) approaches were used to evaluate the association between CD4 (or CD4/CD8 ratio) slope within two years since ART initiation and a composite endpoint (AIDS, serious non-AIDS events and death) after two years of ART. We compared the predictive capacity of four CD4 count metrics (estimated CD4 slope, estimated CD4/CD8 ratio slope during two years following ART initiation and CD4 at 1 and 2 years following ART initiation) using Cox regression models.

Results

We included 2,422 patients. Mean CD4 slope (±standard error) during two years of ART was 102 ± 2 cells/μl/year (95% confidence interval: 98–106 cells/μl/year), this increase was uniform among the three cohorts (p = 0.80). There were 267 composite events after two years on ART. Using the JM approach, a CD4 slope ≥100 cells/μL/year or CD4/CD8 ratio slope >0.1 higher rate per year were associated with lower composite endpoint rates (adjusted hazard ratio [HR] = 0.80, p = 0.04 and HR = 0.75 p<0.01, respectively). All four CD4 metrics showed modest predictive capacity.

Conclusions

Using a complex JM approach, CD4 slope and CD4/CD8 ratio slope the first two years after ART initiation were associated with lower rates of the composite outcome. Moreover, the uniformity observed in the mean CD4 slope regardless of the cohort suggests a common CD4 response pattern independent of age or CD4 nadir. Given the consistency observed with CD4 slope, availability and ease of interpretation, this study provides strong rationale for using CD4 gains <100 cells/μl/year to identify patients at risk for adverse events.

Early antiretroviral treatment of infants to attain HIV remission

BACKGROUND

Studies in adults and children suggested that starting antiretroviral therapy (ART) soon after infection positively influences early events in HIV infection raising the possibility that remission may be achieved in some.

METHODS

We designed an analytic treatment interruption (ATI) trial to test the hypothesis that a sizable minority of HIV-infected neonates who initiated ART <14 days of birth and maintained on ART would be able to maintain viral suppression when ART was withdrawn. To yield the target cohort for this trial, 73 HIV-infected neonates identified at one hospital in Johannesburg, South Africa, were initiated on ART <14 days of birth and maintained on ART tracking viral load (VL) decline and immune recovery (clinicaltrials.gov # NCT02431975).

FINDINGS

Three HIV-infected infants (4.1%) died and nine (12.3%) were lost to follow-up before 48 weeks of age. Of those surviving on study, 52.5% attained and sustained VL <50 copies/ml and half of these sustained CD4+ T-cell percentage >30% which were the primary entry criteria for the ATI trial. Proportions achieving ATI eligibility criteria were similar in the 46 infants starting ART <48 h (19.6%) to 27 infants starting 2-14 days (25.9%) (p = 0.567).

INTERPRETATION

Very early ART on its own, using regimens available when the trial was designed, is insufficient to attain minimum entry criteria needed to justify our trial of ART interruption. Decisions about how quickly to start ART should be based on optimizing standard clinical outcomes rather than with the expectation that remission can be attained.

FUNDING

NICHD/NIAID (U01HD080441), South African Research Chairs Initiative of DST and NRF (South Africa).

Determination of cell expansion and surface molecule expression on anti-CD3/28 expanded CD4+ T cells

CD4⁺ T cell immunotherapy has potential for treatment in HIV-infected patients. A large number of expanded CD4⁺ T cells and confirmation of functional-related phenotypes are required for ensuring the successful outcomes of treatment. Freshly isolated CD4⁺ T cells from healthy donors were activated with anti-CD3/28-coated magnetic beads at different bead-to-cell ratios and cultured in the absence and presence of IL-2 supplementation for 3 weeks. Fold expansion, cell viability, growth kinetic and lymphocyte subset identities were determined. Data demonstrated that a 1:1 bead-to-cell ratio rendered the highest expansion of 1044-fold with 88% viability and 99.5% purity followed by the 2:1 and 0.5:1 ratios. No significant difference in proliferation and phenotypes was found between non-IL-2 and IL-2 supplementation groups. Several specific surface molecule expressions of the expanded cells including chemokine receptors, adhesion molecules, co-stimulatory molecules, activation molecules, maturation markers, cytokine receptors and other molecules were altered when compared to the unexpanded cells. This optimized expansion protocol using the 1:1 bead-to-cell ratio of anti-CD3/28-coated magnetic beads and culture condition without IL-2 supplementation provided the satisfactory yield with good reproducibility. Specific surface molecule expressions of the expanded cells presented potential roles in proliferation, differentiation, homeostasis, apoptosis and organ homing.

Factors Associated with Immune Discordant Responses in Treated HIV-infected Omani Patients

Background:

Despite sustained viral control by antiretroviral therapy (ART), some HIV-infected patients do not recover normal CD4+ T cell counts. This Discordant Immune Response (DIR) increases the risk of opportunistic infections.

Objective:

To evaluate the factors associated with DIR in HIV-infected Omani patients attending public sector clinics.

Methods:

All HIV-infected patients receiving ART with regular follow-up visits were eligible for this study. The DIR group comprised patients on ART for at least two years with plasma HIV viral load < 50 copies/mL and helper CD4+ T cell counts below 350 cells/μl. The Concordant Immune Responses (CIR) group was similar to DIR but with CD4+ T cell counts above 350 cells/μl. Univariate and multivariate analyses using logistic regression models were used to assess the impact of demographic characteristics, clinical, immunological and virological parameters, type of ART regimens, tuberculosis and other opportunistic co-infections on DIR.

Results:

Among 153 enrolled participants, 28 and 76 patients were identified as having DIR and CIR, respectively. The multivariate analysis revealed that the only factors independently associated with DIR after adjustment were age (odds ratio [OR] 1.13; 95% confidence interval [CI] 1.04-1.23), baseline CD4+ T cell count (OR: 0.98; CI: 0.97-0.99) and baseline CD56+ cell count (OR: 0.97; CI: 0.96-0.99).

Conclusion:

Collectively, these findings suggest that a significant proportion of HIV-infected Omani patients develop DIR totaling 27%, and efforts should be made to improve early identification of these patients who tend to experience poor clinical outcomes.

Thymic Function as a Predictor of Immune Recovery in Chronically HIV-Infected Patients Initiating Antiretroviral Therapy

Poor immunological responders (PIR) are HIV-infected patients with virologic suppression upon antiretroviral therapy (ART) but persistently low CD4⁺ T cell counts. Early identification of PIR is important given their higher morbimortality compared to adequate immune responders (AIR). In this study, 33 patients severely lymphopenic at ART onset, were followed for at least 36 months, and classified as PIR or AIR using cluster analysis grounded on their CD4⁺ T cell count trajectories. Based on a variety of immunological parameters, we built predictive models of PIR/AIR outcome using logistic regression. All PIR had CD4⁺ T cell counts consistently below 500 cells/μL, while all AIR reached this threshold. AIR showed a higher percentage of recent thymic emigrants among CD4⁺ T cells; higher numbers of sj-TRECs and greater sj/β TREC ratios; and significant increases in thymic volume from baseline to 12 months of ART. We identified mathematical models that correctly predicted PIR/AIR outcome after 36 months of therapy in 77-87% of the cases, based on observations made until 2-6 months after ART onset. This study highlights the importance of thymic activity in the immune recovery of severely lymphopenic patients, and may help to select the patients that will benefit from closer follow-up or novel therapeutic approaches.

Clinical importance of thrombocytopenia in patients with acute coronary syndromes: a systematic review and meta-analysis

Thrombocytopenia (TP) is common in hospitalized patients. In the context of acute coronary syndromes (ACS), TP has been linked to adverse clinical outcomes. We present a systematic review and meta-analysis of the evidence on the clinical importance of preexisting and in-hospital acquired TP in the context of ACS. Specifically, we address (a) the prevalence and associated factors with TP in the context of ACS; and (b) the association between TP and all-cause mortality, major adverse cardiovascular events (MACEs), and major bleeding. We conducted systematic literature searches in MEDLINE and Web of Science. For the meta-analysis, we fit linear mixed models with a random study-specific intercept for the aggregate outcomes. A total of 16 studies and 190 915 patients were included in this study. Of these patients, 8.8% ± 1.2% presented with preexisting TP while 5.8% ± 1.0% developed TP after hospital admission. Preexisting TP was not statistically significantly associated with adverse outcomes. Acquired TP was associated with greater risk of all-cause mortality (risk difference [RD]: 4.3%; 95% confidence interval [CI]: 2-6%; p = 0.04), MACE (RD: 8.5%; 95% CI: 1-16.0%; p = 0.037), and major bleeding (RD: 11.9%; 95% CI: 5-19%; p = 0.005). In conclusion, TP is a prevalent condition in patients admitted for an ACS and identifies a high-risk patient population more likely to experience ischemic and bleeding complications, as well as higher mortality.

Absolute CD4+ T cell count overstate immune recovery assessed by CD4+/CD8+ ratio in HIV-infected patients on treatment

Objectives

To analyse the correlation and concordance between aCD4, CD4%, CD4/CD8, their intra-patient variability, and to compare the immune recovery (IR) rates based on the three parameters in HIV-infected patients after starting antiretroviral therapy.

Methods

From a prospectively followed cohort, patients who maintained HIV-RNA suppression in ≥95% of the determinations throughout the follow-up were selected. IR was defined as aCD4 >650/μl, CD4% ≥38% or CD4/CD8 ≥1.

Results

A total of 1164 patients with a median follow-up of 5 years were analysed. The increases in aCD4, CD4% and CD4/CD8 were highest during the first year and considerably lower thereafter regardless of baseline aCD4. The annual increases in aCD4 showed poor correlations with those of CD4% (r = 0.143–0.250) and CD4/CD8 (r = 0.101–0.192) but were high between CD4% and CD4/CD8 (r = 0.765–0.844; p<0.001). The median intra-annual coefficients of variation for aCD4, CD4/CD8 and CD4% were 12.5, 8.5 and 6.6, respectively. After five years, 66.7%, 41.6% and 42.1% of the patients reached aCD4 >650/μl, CD4% ≥38%, and CD4/CD8 ≥1, respectively, while only 31% achieved both aCD4 and CD4/CD8 target values.

Conclusions

The increases in aCD4 poorly correlate with those of CD4% and CD4/CD8. IR rates based on aCD4 significantly overstate those obtained by CD4% and CD4/CD8. CD4% and CD4/CD8 are more stable markers than aCD4 and should be taken into account to monitor the IR after treatment initiation.

Immunologic and virological response to ART among HIV infected individuals at a tertiary hospital in Ghana

Background

The need to study the outcome of Antiretroviral Therapy (ART) among Human Immunodeficiency Virus (HIV) infected individuals in Ghana, a sub-Saharan African country crucial in the era of the “Treat All” policy. The aim of this study was to analyze selected determinants of immunological and virological response to ART among HIV infected individuals in a tertiary facility in Cape Coast, Ghana.

Methods

An analytical cross sectional study with a retrospective component was conducted in the Cape Coast Teaching Hospital (CCTH), Central Region. Clients aged 18 years and above attending the HIV Clinics for ART and who were on ART for 6 months or more were recruited. The viral loads, CD4 count and other socio-demographic data were analyzed using STATA version 13 (STATA Corp, Texas USA). Descriptive analysis was done and presented with appropriate measures of central tendencies. In addition, bivariate and multivariate analysis was carried out with p value of 0.05 interpreted as evidence of association between variables.

Results

A total of 440 participants were included in this study with a mean age of 45.5 (±11.6) years. The mean CD4 count at baseline, 6 months on ART and currently at study recruitment were 215.1 cells/mm³ (±152.6), 386.6 cells/mm³ (±178.5), and 579.6 cells/mm³ (±203.0) respectively. After 6 months and 12 months on ART, the number who had achieved viral copies < 1000/ml were 149 (47.0%) and 368 (89.6%) respectively. There was strong evidence of an association between having CD4 count < 350 cells/mm³ after 6 months on ART and having a diagnosis of tuberculosis since HIV diagnosis (aOR 8.5, 95% CI 1.1–73.0, p = 0.05) and clients having plasma viral load > 1000 copies/ml after 6 months on ART (aOR 2.0, 95% CI 1.2–3.2, p = 0.01).

Conclusion

There was good response to ART among clients, high virological suppression and immunological recovery hence low rates of change to second line ART regimen in this cohort studied. With strict adherence to the national policy on HIV testing, management of positive clients and full implementation of the “Treat All” policy, Ghana could achieve, if nothing at all, the third “90, 90, 90” target by 2020.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3142-5) contains supplementary material, which is available to authorized users.

HIV-Specific CD8 T Cells Producing CCL-4 Are Associated With Worse Immune Reconstitution During Chronic Infection

BACKGROUND

Immunological nonresponse represents the Achilles heel in the combination antiretroviral therapy (cART) effectiveness, and increases risk of clinical events and death. CD8 T cells play a crucial role in controlling HIV replication, and polyfunctional HIV-specific CD8 T cells have been associated with nonprogressive HIV infection. However, the possible role of polyfunctional CD8 T cells in predicting posttreatment immune reconstitution has not yet been explored. The aim of this study was to identify functional markers predictive of immunological response to cART in chronic HIV-infected patients.

METHODS

A cohort of chronic HIV-infected individuals naive to cART were enrolled in the ALPHA study. CD4/CD8 T-cell subsets, their differentiation/activation, as well as susceptibility to apoptosis were analyzed before and after 12 months of cART. Moreover, CD8 T cells polyfunctional response after HIV antigenic stimulation was also assessed.

RESULTS

Results showed a significant correlation between worse CD4 T-cell restoration and low frequency of naive CD4 T cells, high frequency of effector memory CD4 T cells, and high susceptibility to apoptosis of CD4 T cells all before cART. Moreover, CD8 functional subsets expressing total C-C motif chemokine ligand 4 (CCL-4) or in combination with CD107a and interferon gamma (IFNγ) were negatively associated with immune reconstitution.

CONCLUSIONS

In conclusion, our study shows that a more differentiated phenotype of CD4 T cells and CCL-4-producing CD8 T cells could represent valuable predictors of worse immune reconstitution. These parameters may be used as tools for identifying patients at risk of immunological failure during cART and eventually represent the basis for innovative therapeutic strategies.