Serum Selenium and Inflammation in Individuals with Human Immunodeficiency Virus Infection

HIV infection has been linked to selenium deficiency and chronic inflammation. Both selenium deficiency and inflammation have been associated with poor health outcomes among individuals with HIV. However, the role of serum selenium levels in inflammation has not been studied among individuals with HIV. We assessed the relationship of serum selenium levels to C-reactive protein (CRP), a marker of inflammation, in individuals with HIV in Kathmandu, Nepal. In this cross-sectional study, we measured the normal serum CRP and selenium levels of 233 individuals with HIV (109 women and 124 men) using the latex agglutination turbidimetric and atomic absorption methods, respectively. We used multiple linear regression analysis in examining the association of serum selenium levels with CRP adjusting for sociodemographic and clinical parameters, including antiretroviral therapy, CD4+ T cell count, chronic diseases, and body mass index. The geometric means of CRP and selenium levels were 1.43 mg/liter and 9.65 μg/dL, respectively. Overall, serum selenium levels were inversely associated with CRP levels (β for one unit change in log selenium; β = -1.01, p = .06). Mean CRP levels significantly decreased with increasing selenium across selenium tertiles (p for trend = .019). The mean serum CRP levels were 40.8% lower in the highest selenium tertile than in the lowest. Our study suggests that high serum selenium levels may reduce serum CRP levels in individuals with HIV, although a longitudinal study is warranted to establish causality.

HIV but Not CMV Replication Alters the Blood Cytokine Network during Early HIV Infection in Men

OBJECTIVE

CMV coinfection contributes to sustained immune activation in people with chronic HIV. In particular, asymptomatic CMV shedding in semen has been associated with increased local and systemic immune activation, even during suppressive antiretroviral therapy (ART). However, the effect of seminal CMV shedding in people with HIV in the earliest phase of HIV infection is not known.

METHODS

Using Luminex, we measured the concentration of 34 cytokines in the blood plasma of sixty-nine men who had sex with men with or without HIV and in subgroups of CMV shedders vs. non-shedders. Differences in blood plasma cytokines between groups were investigated using the multivariate supervised partial least squares discriminant analysis method.

RESULTS

Independently of CMV, we found that concentrations of IP-10, MIG, MCP-1, I-TAC 10, IL-16, and MIP-1β were modulated in the earliest phase of HIV infection compared with control individuals without HIV. In people with HIV, there was no difference in blood cytokines among CMV shedders vs. non-shedders.

CONCLUSION

In early/acute HIV infection, asymptomatic CMV shedding in semen does not drive additional cytokine changes in blood. Early ART initiation should remain the priority, while the added benefit of CMV suppression during the various stages of HIV infection needs to be further investigated.

Mechanisms of immune aging in HIV

Massive CD4+ T-cell depletion as well as sustained immune activation and inflammation are hallmarks of Human Immunodeficiency Virus (HIV)-1 infection. In recent years, an emerging concept draws an intriguing parallel between HIV-1 infection and aging. Indeed, many of the alterations that affect innate and adaptive immune subsets in HIV-infected individuals are reminiscent of the process of immune aging, characteristic of old age. These changes, of which the presumed cause is the systemic immune activation established in patients, likely participate in the immuno-incompetence described with HIV progression. With the success of antiretroviral therapy (ART), HIV-seropositive patients can now live for many years despite chronic viral infection. However, acquired immunodeficiency syndrome (AIDS)-related opportunistic infections have given way to chronic diseases as the leading cause of death since HIV infection. Therefore, the comparison between HIV-1 infected patients and uninfected elderly individuals goes beyond the sole onset of immunosenescence and extends to the deterioration of several physiological functions related to inflammation and systemic aging. In light of this observation, it is interesting to understand the precise link between immune activation and aging in HIV-1 infection to figure out how to best care for people living with HIV (PLWH).

Understanding the interaction between cytomegalovirus and tuberculosis in children: The way forward

Over 1 million children develop tuberculosis (TB) each year, with a quarter dying. Multiple factors impact the risk of a child being exposed to Mycobacterium tuberculosis (Mtb), the risk of progressing to TB disease, and the risk of dying. However, an emerging body of evidence suggests that coinfection with cytomegalovirus (CMV), a ubiquitous herpes virus, impacts the host response to Mtb, potentially influencing the probability of disease progression, type of TB disease, performance of TB diagnostics, and disease outcome. It is also likely that infection with Mtb impacts CMV pathogenesis. Our current understanding of the burden of these 2 diseases in children, their immunological interactions, and the clinical consequence of coinfection is incomplete. It is also unclear how potential interventions might affect disease progression and outcome for TB or CMV. This article reviews the epidemiological, clinical, and immunological literature on CMV and TB in children and explores how the 2 pathogens interact, while also considering the impact of HIV on this relationship. It outlines areas of research uncertainty and makes practical suggestions as to potential studies that might address these gaps. Current research is hampered by inconsistent definitions, study designs, and laboratory practices, and more consistency and collaboration between researchers would lead to greater clarity. The ambitious targets outlined in the World Health Organization End TB Strategy will only be met through a better understanding of all aspects of child TB, including the substantial impact of coinfections.

High prevalence of gastrointestinal manifestations among Cytomegalovirus end-organ disease in the combination antiretroviral era

Background

Cytomegalovirus (CMV) end-organ disease (EOD) continues to pose a significant risk to patients with advanced HIV disease despite decreased incidence with combination anti-retroviral therapy (ART) and lower mortality with effective anti-CMV therapy. Subclinical CMV shedding may also contribute to ongoing inflammation and non-infectious comorbidities.

Methods

We examined the occurrence of CMV EOD and CMV shedding in a cohort of patients participating in a prospective observational study of severely immunosuppressed (CD4 ≤100 cells/μl), ART-naïve, HIV-1 infected adult participants.

Results

We studied 206 participants, of whom 193 (93.7%) were CMV IgG positive. Twenty-five participants (12.1%) developed confirmed CMV EOD. At baseline, 47 (22.8%) had CMV viremia detectable by PCR in the absence of clinical disease (CMV viremia). The remaining 134 (65%) had neither CMV EOD nor CMV viremia detected at baseline. Five participants with CMV EOD (2.4% of total cohort, 20% of CMV EOD) met AIDS Clinical Trials Group criteria for CMV immune reconstitution inflammatory syndrome (IRIS). Only one-third of CMV EOD patients had retinitis, while two-thirds presented with histologically confirmed gastrointestinal illness. CMV viremia was associated with higher percentages of activated CD8⁺ T cells even after HIV suppression.

Conclusion

The manifestations of CMV EOD in advanced HIV disease before and after initiation of ART may be more diverse than previously described, with high incidence of gastrointestinal illness. Recognition and treatment of unusual clinical presentations of CMV infection remains important in reducing morbidity and mortality from HIV co-infections.

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Cytomegalovirus end organ disease (CMV EOD) remains an important complication in HIV/AIDS patients.

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We found that gastrointestinal disease was the most common presentation of CMV EOD.

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In addition, subclinical CMV viremia was associated with increased immune activation.

Stage-Dependent Within-Individual Comparison Reveals SIV-Specific Activation/Exhaustion Shift in Rhesus Macaques

It is challenging to trace the complicated individual-based variations of HIV-specific immunocompetence shift during the successful antiretroviral therapy (ART) era. Using eight rhesus monkeys simulating a longitudinal stage-dependent cohort (baseline-SIV acute infection-SIV suppression by ART-ART withdrawal), baseline immunocompetence monitoring for 28 days (SIV-negative stage, SN) was compared with host immunocompetence undergoing 90-day ART treatment (SIV-suppressed stage, SS) to reveal the SIV-specific immunity shift aroused by undetectable individual viral replication. During acute SIV infection for 98 days (SIV-emerged stage, SE), immune activation was compared with re-immune activation post ART for 49-day follow-up (SIV-rebounded stage, SR) to reveal the SIV-specific immune activation variation aroused by detectable individual viral replication. Individual immunocompetence was measured by co-expression of CD4, CD8, CD38, HLA-DR, CCR7, CD45RA, and PD-1 on T cells and a cytokine panel. Compared with SN, mild immune activation/exhaustion was characterized by increased CD38⁺ HLA-DR^– CD4⁺/CD8⁺ T-cell subsets and PD-1⁺ memory CD4⁺/CD8⁺ T-cell subsets with three elevated cytokines (MIP-1β, IL-8, and IL-10) significantly emerged in SS. Compared with SE, SR produced more exhaustion characterized by increased PD-1⁺ CD4⁺ T_CM cells and decreased PD-1⁺ CD4⁺ T_EM cells with four elevated pro-inflammatory cytokines (IFN-γ, IL-1β, IL-6, and TNF-α). By such individualized stage-dependent comparison, the sustainable immune activation was found from activation/exhaustion shifted into exhaustion during the longitudinal viral persistence. Further, validated SIV accelerates host immunosenescence continuously independent of viral replication.

Assessing the differential impact of chronic CMV and treated HIV infection on CD8+ T-cell differentiation in a matched cohort study: is CMV the key?

BACKGROUND

Cytomegalovirus (CMV) infection is one of the main driving forces of T-cell senescence in the general population, whereas its differential impact in people living with HIV (PLWH) is less well characterized. The study explores the effect of latent CMV infection on T-cell subsets, monocyte/macrophages activation markers, and CRP in PLWH on long-term ART.

METHODS

Cross-sectional cohort study including PLWH on long-term suppressive ART. Individuals of 4 groups (HIV+CMV-, HIV+CMV+, HIV-CMV+, and HIV-CMV-) were matched 1:1:1:1 for age and sex. Immunophenotyping of lymphocyte and T-cell subsets by multicolor flow cytometry was performed in fresh blood samples collected from patients and healthy donors.

RESULTS

Both, latent CMV and treated HIV infection were associated with an expansion of CD8 T cells, a reduced CD4/CD8 ratio, and with CD8 T-cell activation with a cumulative effect in CMV/HIV-coinfected individuals. CMV was associated with elevated numbers of late effector and terminally differentiated CD8 T-cells. Compared to CMV monoinfection, CMV/HIV coinfection showed to be associated with lower proportion of CD28-CD8+ T cells expressing CD57 suggesting that HIV preferentially expands CD28-CD57-CD8+ T cells and impedes terminal differentiation of CD28-CD8+ T cells. We could not show any association between HIV or CMV infection status and concentration of CRP and CD163.

CONCLUSIONS

CMV infection is associated with phenotypic signs of T-cell senescence, promoting exacerbation and persistence of alterations of the T-cell compartment in PLWH on effective ART, which are associated with adverse clinical outcomes and may be an attractive target for therapeutic interventions.

Dual-targeted anti-CMV/anti-HIV-1 heterodimers

Despite the development of efficient anti-human immunodeficiency virus-1 (HIV-1) therapy, HIV-1 associated pathogens remain a major clinical problem. Human cytomegalovirus (CMV) is among the most common HIV-1 copathogens and one of the main causes of persistent immune activation associated with dysregulation of the immune system, cerebrovascular and cardiovascular pathologies, and premature aging. Here, we report on the development of dual-targeted drugs with activity against both HIV-1 and CMV. We synthesized seven compounds that constitute conjugates of molecules that suppress both pathogens. We showed that all seven compounds exhibit low cytotoxicity and efficiently inhibited both viruses in cell lines. Furthermore, we chose a representative compound and demonstrated that it efficiently suppressed replication of HIV-1 and CMV in human lymphoid tissue ex vivo coinfected with both viruses. Further development of such compounds may lead to the development of dual-targeted anti-CMV/HIV-1 drugs.

Immunological Aspects of Diagnosis and Management of Childhood Tuberculosis

The diagnosis of tuberculosis (TB) in children is difficult because of the low sensitivity and specificity of traditional microbiology techniques in this age group. Whereas in adults the culture of Mycobacterium tuberculosis (M. tuberculosis), the gold standard test, detects 80% of positive cases, it only detects around 30-40% of cases in children. The new methods based on the immune response to M. tuberculosis infection could be affected by many factors. It is necessary to evaluate the medical record, clinical features, presence of drug-resistant M. tuberculosis strains, comorbidities, and BCG vaccination history for the diagnosis in children. There is no ideal biomarker for all TB cases in children. A new strategy based on personalized diagnosis could be used to evaluate specific molecules produced by the host immune response and make therapeutic decisions in each child, thereby changing standard immunological signatures to personalized signatures in TB. In this way, immune diagnosis, prognosis, and the use of potential immunomodulators as adjunct TB treatments will meet personalized treatment.

Residual immune dysfunction under antiretroviral therapy

The usage of combination antiretroviral therapy in people with HIV (PWH) has incited profound improvement in morbidity and mortality. Yet, PWH may not experience full restoration of immune function which can manifest with non-AIDS comorbidities that frequently associate with residual inflammation and can imperil quality of life or longevity. In this review, we discuss the pathogenesis underlying chronic inflammation and residual immune dysfunction in PWH, as well as potential therapeutic interventions to ameliorate them and prevent incidence or progression of non-AIDS comorbidities. Current evidence advocates that early diagnosis and prompt initiation of therapy at high CD4 counts may represent the best available approach for an improved immune recovery in PWH.

High microbial translocation limits gut immune recovery during short-term HAART in the area with high prevalence of foodborne infection

BACKGROUND

Individuals residing in areas with high prevalence of foodborne infection could have a higher risk of gut microbial translocation which may affect monocyte activation, gut immune recovery and intestinal epithelial cell damage. We aimed to measure alterations in microbial translocation, monocyte activation, gut immune recovery, and intestinal epithelial cell damage in HAART treated individuals.

METHODS

A prospective, single-arm, longitudinal, cohort study was conducted among antiretroviral naïve HIV-1 infected Thai participants. All participants were in chronic stage of HIV-1 infection before starting HAART. Data and samples were collected prior to initiation of HAART and then after 24 and 48 weeks of HAART. Plasma biomarkers for microbial translocation (16S rDNA and LBP), monocyte activation (sCD14) and intestinal epithelial cell damage (I-FABP) were evaluated. We measured circulating gut-homing CD4⁺ T cells and circulating gut-homing Th17 cells to assess recoveries of gut immunity and gut immunity to microbial pathogens.

RESULTS

The kinetic studies showed no reduction in the levels of plasma 16S rDNA, sCD14 or I-FABP, significant decrease of plasma LBP level, and slow but significant increases in the frequencies of circulating gut-homing CD4⁺ T cells and circulating gut-homing Th17 cells during 48 weeks of HAART. Dividing participants into low and high microbial translocation (low and high MT) groups at baseline, both groups showed persistent plasma levels of 16S rDNA, sCD14 and I-FABP, and significantly decreased plasma level of LBP. The low MT group had significantly increased frequencies of circulating gut-homing CD4⁺ T cells and circulating gut-homing Th17 cells during 48 weeks of HAART but this was not observed in the high MT group.

CONCLUSIONS

We demonstrated persistent high microbial translocation, monocyte activation and intestinal epithelial cell damage with slow gut immune recovery during successful short-term HAART. Additionally, gut immune recovery was apparently limited by high microbial translocation. Our findings emphasize the adverse impact of high microbial translocation on gut immune recovery and the necessity of establishing a novel therapeutic intervention to inhibit microbial translocation.

The Potential of Immune Modulation in Therapeutic HIV-1 Vaccination

We discuss here some of the key immunological elements that are at the crossroads and need to be combined to develop a potent therapeutic HIV-1 vaccine. Therapeutic vaccines have been commonly used to enhance and/or recall pre-existing HIV-1-specific cell-mediated immune responses aiming to suppress virus replication. The current success of immune checkpoint blockers in cancer therapy renders them very attractive to use in HIV-1 infected individuals with the objective to preserve the function of HIV-1-specific T cells from exhaustion and presumably target the persistent cellular reservoir. The major latest advances in our understanding of the mechanisms responsible for virus reactivation during therapy-suppressed individuals provide the scientific basis for future combinatorial therapeutic vaccine development.

Grant M. The Immune Response Against Human Cytomegalovirus Links Cellular to Systemic Senescence

Aging reflects long-term decline in physiological function and integrity. Changes arise at a variable pace governed by time-dependent and -independent mechanisms that are themselves complex, interdependent and variable. Molecular decay produces inferior cells that eventually dominate over healthy counterparts in tissues they comprise. In a form of biological entropy, progression from molecular through cellular to tissue level degeneration culminates in organ disease or dysfunction, affecting systemic health. To better understand time-independent contributors and their potential modulation, common biophysical bases for key molecular and cellular changes underlying age-related physiological deterioration must be delineated. This review addresses the potential contribution of cytomegalovirus (CMV)-driven T cell proliferation to cellular senescence and immunosenescence. We first describe molecular processes imposing cell cycle arrest, the foundation of cellular senescence, then focus on the unique distribution, phenotype and function of CMV-specific CD8⁺ T cells in the context of cellular senescence and "inflammaging". Their features position CMV infection as a pathogenic accelerant of immune cell proliferation underlying immune senescence. In human immunodeficiency virus (HIV) infection, where increased inflammation and exaggerated anti-CMV immune responses accelerate immune senescence, CMV infection has emerged as a major factor in unhealthy aging. Thus, we speculate on mechanistic links between CMV-specific CD8⁺ T-cell expansion, immune senescence and prevalence of age-related disorders in HIV infection.

Cytomegalovirus infection is a risk factor for tuberculosis disease in infants

Immune activation is associated with increased risk of tuberculosis (TB) disease in infants. We performed a case-control analysis to identify drivers of immune activation and disease risk. Among 49 infants who developed TB disease over the first 2 years of life, and 129 healthy matched controls, we found the cytomegalovirus-stimulated (CMV-stimulated) IFN-γ response to be associated with CD8+ T cell activation (Spearman's rho, P = 6 × 10-8). A CMV-specific IFN-γ response was also associated with increased risk of developing TB disease (conditional logistic regression; P = 0.043; OR, 2.2; 95% CI, 1.02-4.83) and shorter time to TB diagnosis (Log Rank Mantel-Cox, P = 0.037). CMV+ infants who developed TB disease had lower expression of NK cell-associated gene signatures and a lower frequency of CD3-CD4-CD8- lymphocytes. We identified transcriptional signatures predictive of TB disease risk among CMV ELISpot-positive (area under the receiver operating characteristic [AUROC], 0.98, accuracy, 92.57%) and -negative (AUROC, 0.9; accuracy, 79.3%) infants; the CMV- signature was validated in an independent infant study (AUROC, 0.71; accuracy, 63.9%). A 16-gene signature that previously identified adolescents at risk of developing TB disease did not accurately classify case and control infants in this study. Understanding the microbial drivers of T cell activation, such as CMV, could guide new strategies for prevention of TB disease in infants.

Microbial Translocation Does Not Drive Immune Activation in Ugandan Children Infected With HIV

Objective

Immune activation is associated with morbidity and mortality during human immunodeficiency virus (HIV) infection, despite receipt of antiretroviral therapy (ART). We investigated whether microbial translocation drives immune activation in HIV-infected Ugandan children.

Methods

Nineteen markers of immune activation and inflammation were measured over 96 weeks in HIV-infected Ugandan children in the CHAPAS-3 Trial and HIV-uninfected age-matched controls. Microbial translocation was assessed using molecular techniques, including next-generation sequencing.

Results

Of 249 children included, 142 were infected with HIV; of these, 120 were ART naive, with a median age of 2.8 years (interquartile range [IQR], 1.7–4.0 years) and a median baseline CD4⁺ T-cell percentage of 20% (IQR, 14%–24%), and 22 were ART experienced, with a median age of 6.5 years (IQR, 5.9–9.2 years) and a median baseline CD4⁺ T-cell percentage of 35% (IQR, 31%–39%). The control group comprised 107 children without HIV infection. The median increase in the CD4⁺ T-cell percentage was 17 percentage points (IQR, 12–22 percentage points) at week 96 among ART-naive children, and the viral load was <100 copies/mL in 76% of ART-naive children and 91% of ART-experienced children. Immune activation decreased with ART use. Children could be divided on the basis of immune activation markers into the following 3 clusters: in cluster 1, the majority of children were HIV uninfected; cluster 2 comprised a mix of HIV-uninfected children and HIV-infected ART-naive or ART-experienced children; and in cluster 3, the majority were ART naive. Immune activation was low in cluster 1, decreased in cluster 3, and persisted in cluster 2. Blood microbial DNA levels were negative or very low across groups, with no difference between clusters except for Enterobacteriaceae organisms (the level was higher in cluster 1; P < .0001).

Conclusion

Immune activation decreased with ART use, with marker clustering indicating different activation patterns according to HIV and ART status. Levels of bacterial DNA in blood were low regardless of HIV status, ART status, and immune activation status. Microbial translocation did not drive immune activation in this setting.

Clinical Trials Registration

ISRCTN69078957.

Determinants of Restoration of CD4 and CD8 Cell Counts and Their Ratio in HIV-1-Positive Individuals With Sustained Virological Suppression on Antiretroviral Therapy

BACKGROUND

An increasing number of HIV-positive individuals now start antiretroviral therapy (ART) with high CD4 cell counts. We investigated whether this makes restoration of CD4 and CD8 cell counts and the CD4:CD8 ratio during virologically suppressive ART to median levels seen in HIV-uninfected individuals more likely and whether restoration depends on gender, age, and other individual characteristics.

METHODS

We determined median and quartile reference values for CD4 and CD8 cell counts and their ratio using cross-sectional data from 2309 HIV-negative individuals. We used longitudinal measurements of 60,997 HIV-positive individuals from the Antiretroviral Therapy Cohort Collaboration in linear mixed-effects models.

RESULTS

When baseline CD4 cell counts were higher, higher long-term CD4 cell counts and CD4:CD8 ratios were reached. Highest long-term CD4 cell counts were observed in middle-aged individuals. During the first 2 years, median CD8 cell counts converged toward median reference values. However, changes were small thereafter and long-term CD8 cell count levels were higher than median reference values. Median 8-year CD8 cell counts were higher when ART was started with <250 CD4 cells/mm. Median CD4:CD8 trajectories did not reach median reference values, even when ART was started at 500 cells/mm.

DISCUSSION

Starting ART with a CD4 cell count of ≥500 cells/mm makes reaching median reference CD4 cell counts more likely. However, median CD4:CD8 ratio trajectories remained below the median levels of HIV-negative individuals because of persisting high CD8 cell counts. To what extent these subnormal immunological responses affect specific clinical endpoints requires further investigation.

Cytomegalovirus-Specific CD4+ T-cell Responses and CMV-IgG Levels Are Associated With Neurocognitive Impairment in People Living With HIV

BACKGROUND

Mechanisms leading to neurocognitive impairment (NCI) in people living with HIV (PLWHIV) on stable combination antiretroviral therapy (cART) remain unknown. We investigated the association between immunity against cytomegalovirus (CMV), HIV-specific variables, and NCI in PLWHIV on stable cART and with low comorbidity.

METHODS

Fifty-two PLWHIV on stable cART and 31 HIV-uninfected controls matched on age, sex, education, and comorbidity were tested with a neurocognitive test battery, and CMV-immunoglobulin G (CMV-IgG) levels were measured. In PLWHIV, CMV-specific (CMV-pp65 and CMV-gB) CD4 and CD8 T-cell responses were measured using intracellular cytokine staining and flow cytometry. NCI was defined as a global deficit scale score (GDS score) ≥0.5. GDS scores and domain-specific scores defined severity of NCI. Logistic and linear multivariable regression analyses were used.

RESULTS

NCI was detected in 30.8% of PLWHIV, and HIV was associated with an adjusted odds ratio (aOR) of 5.18 [95% confidence interval (CI): 1.15 to 23.41, P = 0.033] for NCI. In PLWHIV, higher CMV-specific CD4 T-cell responses increased the probability of NCI with an aOR of 1.68 (95% CI: 1.10 to 2.57) for CMV-pp65 or an aOR of 3.73 (95% CI: 1.61 to 16.98) for CMV-gB, respectively. Similar associations were not found with CMV-IgG or CMV-specific CD8 T cells, but when assessing severity of NCI, higher CMV-IgG (per 100 U/mL) was associated with worse GDS scores (β = 0.08) (0.01-0.16), P = 0.044), specifically in the domain of speed of information processing (β = 0.20 (0.04-0.36, P = 0.019).

CONCLUSIONS

PLWHIV had increased risk of NCI. Excess risk may be associated with CMV-specific CD4 T-cell responses and CMV-IgG. Larger longitudinal studies investigating the impact of immunity against CMV on risk of NCI are warranted.

Impact of individual-level factors on Ex vivo mycobacterial growth inhibition: Associations of immune cell phenotype, cytomegalovirus-specific response and sex with immunity following BCG vaccination in humans

Understanding factors associated with varying efficacy of Bacillus Calmette-Guérin (BCG) would aid the development of improved vaccines against tuberculosis (TB). In addition, investigation of individual-level factors affecting mycobacterial-specific immune responses could provide insight into confounders of vaccine efficacy in clinical trials. Mycobacterial growth inhibition assays (MGIA) have been developed to assess vaccine immunogenicity ex vivo and provide a measure of immune function against live mycobacteria. In this study, we assessed the impact of immune cell phenotype, cytomegalovirus (CMV)-specific response and sex on ex vivo growth inhibition following historical BCG vaccination in a cohort of healthy individuals (n = 100). A higher frequency of cytokine-producing NK cells in peripheral blood was associated with enhanced ex vivo mycobacterial growth inhibition following historical BCG vaccination. A CMV-specific response was associated with T-cell activation, a risk factor for TB disease and we also observed an association between T-cell activation and ex vivo mycobacterial growth. Interestingly, BCG-vaccinated females in our cohort controlled mycobacterial growth better than males. In summary, our present study has shown that individual-level factors influence capacity to control mycobacterial growth following BCG vaccination and the MGIA could be used as a tool to assess how vaccine candidates may perform in different populations.

Cytomegalovirus Viremia in HIV-1 Subtype C Positive Women at Delivery in Botswana and Adverse Birth/Infant Health Outcomes

BACKGROUND

We evaluated the association between maternal cytomegalovirus (CMV) viremia during pregnancy and adverse birth and infant health outcomes in HIV-infected mothers and their HIV-exposed uninfected infants.

METHODS

HIV-positive women and their infants were followed prospectively from pregnancy through 2 years postpartum in the "Tshipidi" study in Botswana. We analyzed the association between detectable CMV DNA in maternal blood at delivery and adverse birth outcomes (stillbirth, preterm delivery, small for gestational age, or birth defect), as well as infant hospitalization and mortality through 24 months.

RESULTS

We measured CMV DNA in blood samples from 350 (77.1%) of 454 HIV-positive women from the Tshipidi study. The median maternal CD4 count was 422 cells/mL, and median HIV-1 RNA at entry was 3.2 log10 copies/mL. Fifty-one (14.6%) women had detectable CMV DNA. In unadjusted analyses, detectable CMV DNA was associated with higher maternal HIV-1 RNA [odds ratio (OR) 1.4, 95% confidence interval (CI): 1.1 to 1.9], presence of a birth defect (OR 9.8, 95% CI: 1.6 to 60.3), and occurrence of any adverse birth outcome (OR 2.0, 95% CI: 1.04 to 3.95). In multivariable analysis, we observed a trend toward association between detectable maternal CMV DNA and occurrence of any adverse birth outcome (adjusted OR 1.9, 95% CI: 0.96 to 3.8). Maternal CMV viremia was not associated with infant hospitalization and/or death by 24 months.

CONCLUSIONS

Approximately 1 in 6 HIV-positive women in Botswana had detectable CMV DNA in blood at delivery. The presence of maternal CMV viremia had a borderline association with adverse birth outcomes but not with 24-month morbidity or mortality in HIV-exposed uninfected children.

HIV, HCMV and mycobacterial antibody levels: a cross-sectional study in a rural Ugandan cohort

OBJECTIVES

A growing evidence base implicates human cytomegalovirus (HCMV) as a risk factor for TB disease. We investigated total IgG and mycobacteria-specific antibodies in a cross-sectional study nested within a rural Ugandan General Population Cohort (GPC), in relation to HIV infection and the magnitude of HCMV IgG response.

METHODS

Sera from 2189 individuals (including 27 sputum-positive TB cases) were analysed for antibodies against mycobacteria (Ag85A, PPD, LAM, ESAT6/CFP10) and HCMV, tetanus toxoid (TT) and total IgG.

RESULTS

Anti-mycobacterial antibodies increased with age until approximately 20 years, when they plateaued. Higher HCMV exposure (measured by IgG) was associated with lower levels of some anti-mycobacterial antibodies, but no increase in total IgG. HIV infection was associated with a decrease in all anti-mycobacterial antibodies measured and with an increase in total IgG.

CONCLUSIONS

The increase in anti-mycobacterial antibodies with age suggests increasing exposure to non-tuberculous mycobacteria (NTM), and to M.tb itself. HIV infection is associated with decreased levels of all mycobacterial antibodies studied here, and high levels of HCMV IgG are associated with decreased levels of some mycobacterial antibodies. These findings point towards the importance of humoral immune responses in HIV/TB co-infection and highlight a possible role of HCMV as a risk factor for TB disease.

HIV infection and care pathway: From guidelines to clinical practice

OBJECTIVES

To quantify within a cohort of HIV-infected individuals the number of medical visits and procedures to be carried out according to comorbidities and risk factors to implement a personalized care pathway.

PATIENTS AND METHODS

Retrospective study of 915 patients consulting from January 1 to December 31, 2016 at an outpatient unit of multidisciplinary consultations, using an electronic patient record. We built an algorithm using parameters required for the application of the national guidelines for the management of HIV-infected individuals. The frequency of comorbidities was measured according to gender, transmission risk group, and nadir CD4 (<or>200/mm³).

RESULTS

Patients were mostly men (median age: 52 years), of whom 16% were aged≥60 years. Viral load was<40 copies/mL in 93.5% of treated patients and CD4 cell count≥500/mm³ for 73%. Overall, 74.5% of patients had at least one comorbidity. The number of comorbidities was similar in men and women but was significantly higher in patients with a nadir CD4 <200/mm3 and increased with age (irrespective of gender). The minimum number of consultations to be scheduled per year was 8123: 70% for the management of comorbidities with an average of six consultations/year/patient. Overall, 53% of patients should attend a proctology consultation. The minimum number of paramedical procedures to be performed was 5115.

CONCLUSION

The implementation of a personalized multidisciplinary management within a single facility seems to be a suitable care model to address the needs of HIV-infected individuals.

Prevalence and clinical characteristics of CMV coinfection among HIV infected individuals in Guinea-Bissau: a cross-sectional study

OBJECTIVES

To describe the prevalence of CMV in a cohort of HIV infected individuals in Guinea-Bissau, West Africa and to evaluate differences in patients' clinical characteristics associated with their CMV status.

METHODS

Newly diagnosed HIV infected adults were invited to participate in this cross-sectional study, from May until December 2015. Enrolled patients were interviewed and underwent a full physical examination focusing on CMV disease manifestations. Blood samples were analysed for CMV serology, QuantiFERON-CMV response and CMV DNA. Mortality follow-up were registered for one year after inclusion.

RESULTS

In total, 180 patients were enrolled. Anti-CMV IgG positivity was found in 100% (138/138) and 2.8% (4/138) were anti-CMV IgM positive. A positive QuantiFERON-CMV response was found in 85.7% (60/70) of the patients and 60.6% (83/137) had CMV viraemia. QuantiFERON-CMV response and detectable CMV DNA were associated with lower CD4 cell count, older age and upper gastrointestinal complaints. During one year of follow-up, the IRR for death among CMV DNA positive patients was 1.5 (P = 0.5).

CONCLUSIONS

CMV coinfection was detected among all enrolled patients and CMV viraemia was highly prevalent. Only age and upper gastrointestinal complaints were associated with the patients' CMV status.

Impact of Aging, Cytomegalovirus Infection, and Long-Term Treatment for Human Immunodeficiency Virus on CD8+ T-Cell Subsets

Both healthy aging and human immunodeficiency virus (HIV) infection lead to a progressive decline in naive CD8⁺ T-cell numbers and expansion of the CD8⁺ T-cell memory and effector compartments. HIV infection is therefore often considered a condition of premature aging. Total CD8⁺ T-cell numbers of HIV-infected individuals typically stay increased even after long-term (LT) combination antiretroviral treatment (cART), which is associated with an increased risk of non-AIDS morbidity and mortality. The causes of these persistent changes in the CD8⁺ T-cell pool remain debated. Here, we studied the impact of age, CMV infection, and LT successful cART on absolute cell numbers in different CD8⁺ T-cell subsets. While naïve CD8⁺ T-cell numbers in cART-treated individuals (N = 38) increased to healthy levels, central memory (CM), effector memory (EM), and effector CD8⁺ T-cell numbers remained higher than in (unselected) age-matched healthy controls (N = 107). Longitudinal analysis in a subset of patients showed that cART did result in a loss of memory CD8⁺ T-cells, mainly during the first year of cART, after which memory cell numbers remained relatively stable. As CMV infection is known to increase CD8⁺ T-cell numbers in healthy individuals, we studied whether any of the persistent changes in the CD8⁺ T-cell pools of cART-treated patients could be a direct reflection of the high CMV prevalence among HIV-infected individuals. We found that EM and effector CD8⁺ T-cell numbers in CMV⁺ healthy individuals (N = 87) were significantly higher than in CMV^- (N = 170) healthy individuals. As a result, EM and effector CD8⁺ T-cell numbers in successfully cART-treated HIV-infected individuals did not deviate significantly from those of age-matched CMV⁺ healthy controls (N = 39). By contrast, CM T-cell numbers were quite similar in CMV⁺ and CMV^- healthy individuals across all ages. The LT expansion of the CM CD8⁺ T-cell pool in cART-treated individuals could thus not be attributed directly to CMV and was also not related to residual HIV RNA or to the presence of HIV-specific CM T-cells. It remains to be investigated why the CM CD8⁺ T-cell subset shows seemingly irreversible changes despite years of effective treatment.

Cytomegalovirus-specific T-cells are associated with immune senescence, but not with systemic inflammation, in people living with HIV

In people living with HIV (PLWHIV), coinfection with cytomegalovirus (CMV) has been associated with inflammation, immunological ageing, and increased risk of severe non-AIDS related comorbidity. The effect of CMV-specific immune responses on systemic inflammation, immune activation and T-cell senescence was evaluated in 53 PLWHIV treated with combination antiretroviral therapy (cART). Activated-, terminally differentiated-, naïve-, and senescent T-cells were assessed by flow cytometry, and plasma levels of CMV IgG, interleukin-6, tumor necrosis factor-α, high-sensitivity C-reactive protein and soluble-CD14 were measured. In PLWHIV, expression of interleukin-2, tumor necrosis factor-α and interferon-γ was measured by intracellular-cytokine-staining after stimulation of T-cells with CMV-pp65, CMV-IE1, and CMV-gB. Increased CMV-specific T-cell responses were associated with a higher ratio of terminally differentiated/naïve CD8+ T-cells and with increased proportions of senescent CD8+ T-cells, but not with systemic inflammation or sCD14. Increased CMV-specific CD4+ T-cell responses were associated with increased proportions of activated CD8+ T-cells. In PLWHIV with expansion of CMV-specific T-cells or increased T-cell senescence, CMV-specific polyfunctionality was maintained. That the magnitude of the CMV-specific T-cell response was associated with a senescent immune phenotype, suggests that a dysregulated immune response against CMV may contribute to the immunological ageing often described in PLWHIV despite stable cART.

Social determinants and BCG efficacy: a call for a socio-biological approach to TB prevention

A high burden of TB mortality persists despite the long-term availability of the bacillus Calmette-Guérin (BCG) vaccine, whose efficacy has been highly variable across populations. Innovative and alternative approaches to TB prevention are urgently needed while optimal biomedical tools continue to be developed. We call for new interdisciplinary collaborations to expand and integrate our understanding of how social determinants influence the biological processes that lead to TB disease, how this translates into differential BCG efficacy and, ultimately, how social protection interventions can play a role in reducing the global burden of TB. After providing an overview of the immune pathways important for the establishment of a response to the BCG vaccine, we outline how social determinants and psychosocial stressors can contribute to the observed variation in BCG efficacy above and beyond these biological factors. We conclude by proposing a new interdisciplinary research model based on the integration of social epidemiology theories with biomedical knowledge.

Proximity of Cytomegalovirus-Specific CD8+ T Cells to Replicative Senescence in Human Immunodeficiency Virus-Infected Individuals

Antiretroviral therapy (ART) effectively extends the life expectancy of human immunodeficiency virus (HIV)-infected individuals; however, age-related morbidities have emerged as major clinical concerns. In this context, coinfection with cytomegalovirus (CMV) accelerates immune senescence and elevates risk for other age-related morbidities, possibly through increased inflammation. We investigated potential relationships between CMV memory inflation, immune senescence, and inflammation by measuring markers of inflammation and telomere lengths of different lymphocyte subsets in HIV-infected individuals seropositive for anti-CMV antibodies. Our study cohort consists mainly of middle aged men who have sex with men (MSM) and heterosexuals who are stable under long-term ART. Median levels of IL-6, TNF-α, and CRP were significantly higher in those coinfected with CMV. Lymphocyte telomere length in general correlated with age, but for 32/32 subjects tested, there was a consistent hierarchy of telomere lengths with CD8⁺ T cells’ shorter than the general lymphocyte population, CD57⁺CD8⁺ T cells’ shorter than CD8⁺ T cells’ and CMV-specific CD57⁺CD8⁺ T cells’ the shortest of all. Telomeres of HIV-specific CD8⁺ T cells were longer than those of CMV-specific CD8⁺ T cells in all cases tested and over 10 years, CMV-specific CD8⁺ T cell telomeres of two HIV-infected individuals eroded faster than those of HIV-specific CD8⁺ T cells. These data indicate that CMV-specific CD8⁺ T cells of HIV-infected individuals are the lymphocytes closest to telomere-imposed replicative senescence. Exhaustive proliferation of CMV-specific CD8⁺ T cells in HIV-infected individuals is a potential source of senescent lymphocytes affecting systemic immune function and inflammation.

Human cytomegalovirus epidemiology and relationship to tuberculosis and cardiovascular disease risk factors in a rural Ugandan cohort

Human cytomegalovirus (HCMV) infection has been associated with increased mortality, specifically cardiovascular disease (CVD), in high-income countries (HICs). There is a paucity of data in low- and middle-income countries (LMICs) where HCMV seropositivity is higher. Serum samples from 2,174 Ugandan individuals were investigated for HCMV antibodies and data linked to demographic information, co-infections and a variety of CVD measurements. HCMV seropositivity was 83% by one year of age, increasing to 95% by five years. Female sex, HIV positivity and active pulmonary tuberculosis (TB) were associated with an increase in HCMV IgG levels in adjusted analyses. There was no evidence of any associations with risk factors for CVD after adjusting for age and sex. HCMV infection is ubiquitous in this rural Ugandan cohort from a young age. The association between TB disease and high HCMV IgG levels merits further research. Known CVD risk factors do not appear to be associated with higher HCMV antibody levels in this Ugandan cohort.

Cross-sectional study of CD4: CD8 ratio recovery in young adults with perinatally acquired HIV-1 infection

Antiretroviral therapy (ART) has improved survival into adulthood for young people with perinatally acquired HIV-1 (yp-PaHIV), but long-term prognosis remains unclear. We hypothesized that on-going immune activation, reflected in the failure of CD4:CD8 ratio normalization would be observed in yp-PaHIV, despite ART.A cross-sectional study of routinely collected clinical data from a cohort of yp-PaHIV (≥16 years).Data were collected from records of individuals attending a specialist clinic for yp-PaHIV transitioning to adult care. CD4:CD8 ratio and proportion with CD4:CD8 ratio ≥1, demographic data and viral parameters, including HIV-1 viral load (VL) and human cytomegalovirus (CMV) IgG, were analyzed with IBM SPSS Statistics v22.A total of 115 yp-PaHIV, median (IQR) age 22.0 (20.0-24.0) years, were studied, of whom 59 were females, and the majority were Black African 75/115 (65.2%). Where measured, CMV antibodies were frequently detected (71/74, 95.9%) and CMV IgG titre was inversely associated with CD4:CD8 ratio, (Rho -0.383, P = .012). Of those taking ART, 69 out of 90 (76.7%) yp-PaHIV had suppressed HIV viremia (<50 RNA copies/mL) and recovery of CD4:CD8 ratio to ≥1 was seen in 26 out of 69 (37.7%) with suppressed HIV viremia. Persistence of low CD4:CD8 ratio was observed even in those with a CD4 count ≥500 cells/μL, where 28/52 (53.8%) had a CD4:CD8 ratio <1. Of those with suppressed viremia, the median (IQR) age for starting ART was 8.0 (5.0-12.8) years and CD4:CD8 ratio was inversely associated with age at ART start, Rho -0.348, (P = .028).In this cohort of yp-PaHIV, despite lifelong HIV infection and widespread CMV coinfection, CD4:CD8 ratio recovery rate was comparable to adults treated in acute infection. Where persistence of CD4:CD8 ratio abnormality was observed, on-going immune activation may have significance for non-AIDS outcomes. Taken together our findings indicate immune resilience to be a feature of these adult survivors of perinatally acquired HIV infection, which can be supported with early antiretroviral therapy.

HIV/Human herpesvirus co-infections: Impact on tryptophan-kynurenine pathway and immune reconstitution

BACKGROUND

Co-infections with human herpesvirus (HHV) have been associated with residual chronic inflammation in antiretroviral (ART)-treated human immunodeficiency virus (HIV)-infected individuals. However, the role of HHV in modulating the tryptophan-kynurenine pathway and clinical outcomes in HIV-infected individuals is poorly understood. Thus, we investigated the seroprevalence of four common HHVs among treated HIV-infected participants and their impact on kynurenine/tryptophan (K/T) ratio and long-term CD4 T-cell recovery in HIV/HHV co-infected participants.

METHOD

In this cross-sectional study, HIV-infected participants receiving suppressive ART for a minimum of 12 months were recruited from the University Malaya Medical Centre (UMMC), Malaysia. Stored plasma was analyzed for CMV, VZV, HSV-1 and HSV-2 IgG antibody levels, immune activation markers (interleukin-6, interferon-γ, neopterin and sCD14), kynurenine and tryptophan concentrations. The influence of the number of HHV co-infection and K/T ratio on CD4 T-cell recovery was assessed using multivariate Poisson regression.

RESULTS

A total of 232 HIV-infected participants were recruited and all participants were seropositive for at least one HHV; 96.1% with CMV, 86.6% with VZV, 70.7% with HSV-1 and 53.9% with HSV-2. K/T ratio had a significant positive correlation with CMV (rho = 0.205, p = 0.002), VZV (rho = 0.173, p = 0.009) and a tendency with HSV-2 (rho = 0.120, p = 0.070), with CMV antibody titer demonstrating the strongest modulating effect on K/T ratio among the four HHVs assessed in SOM analysis. In multivariate analysis, higher K/T ratio (p = 0.03) and increasing number of HHV co-infections (p<0.001) were independently associated with poorer CD4 T-cell recovery following 12 months of ART initiation.

CONCLUSION

Multiple HHV co-infections are common among ART-treated HIV-infected participants in the developing country setting and associated with persistent immune activation and poorer CD4 T-cell recovery.

Serum albumin levels and depression in people living with Human Immunodeficiency Virus infection: a cross-sectional study

BACKGROUND

Lower serum albumin levels and depression are common among HIV-infected persons. High serum albumin levels may provide protection against depression through its defensive role in inflammation and infection. We tested the hypothesis of an independent relationship between serum albumin levels and depressive symptoms in a cohort of HIV-infected persons.

METHODS

A cross-sectional survey was conducted among 310 HIV-infected persons (176 men and 134 women) aged 20-60years residing in the Kathmandu Valley, Nepal. The bromocresol green method was used to measure serum albumin levels and the Beck Depression Inventory method was used to measure depressive symptoms, with a cut off score of 20 or higher indicating likely depression. The relationship between serum albumin levels and depressive symptoms was assessed using both multiple linear regression analysis and multiple logistic regression analysis, with adjustment for sociodemographic, cardiovascular, life-style, and HIV-related clinical and treatment confounding factors.

RESULTS

Serum albumin levels were inversely associated with depressive symptoms scores (beta for 1 unit change in serum albumin levels: β=-3.91; p=0.001) for the total participant sample. This inverse association was significant in both men (β=-3.93; p=0.009) and women (β=-4.47; p=0.03). A significantly decreased risk of depression was observed among participants with the highest serum albumin levels, with odds ratio and 95% CI for those with >5.0g/dL versus <4.0g/dL of 0.22 (0.06-0.80) (p=0.01).

CONCLUSION

Serum albumin levels were inversely associated with depressive symptoms scores in HIV-infected persons.

Terminal differentiation of T cells is strongly associated with CMV infection and increased in HIV-positive individuals on ART and lifestyle matched controls

HIV-1-positive individuals on successful antiretroviral therapy (ART) are reported to have higher rates of age-associated non-communicable comorbidities (AANCCs). HIV-associated immune dysfunction has been suggested to contribute to increased AANCC risk. Here we performed a cross-sectional immune phenotype analysis of T cells in ART-treated HIV-1-positive individuals with undetectable vireamia (HIV-positives) and HIV-1-negative individuals (HIV-negatives) over 45 years of age. In addition, two control groups were studied: HIV negative adults selected based on lifestyle and demographic factors (Co-morBidity in Relation to AIDS, or COBRA) and unselected age-matched donors from a blood bank. Despite long-term ART (median of 12.2 years), HIV-infected adults had lower CD4⁺ T-cell counts and higher CD8⁺ T-cell counts compared to well-matched HIV-negative COBRA participants. The proportion of CD38⁺HLA-DR⁺ and PD-1⁺ CD4⁺ T-cells was higher in HIV-positive cohort compared to the two HIV-negative cohorts. The proportion CD57⁺ and CD27⁻CD28⁻ cells of both CD4⁺ and CD8⁺ T-cells in HIV-positives was higher compared to unselected adults (blood bank) as reported before but this difference was not apparent in comparison with well-matched HIV-negative COBRA participants. Multiple regression analysis showed that the presence of an increased proportion of terminally differentiated T cells was strongly associated with CMV infection. Compared to appropriately selected HIV-negative controls, HIV-positive individuals on ART with long-term suppressed viraemia exhibited incomplete immune recovery and increased immune activation/exhaustion. CMV infection rather than treated HIV infection appears to have more consistent effects on measures of terminal differentiation of T cells.

Assessing immune aging in HIV-infected patients

Many of the alterations that affect innate and adaptive immune cell compartments in HIV-infected patients are reminiscent of the process of immune aging, characteristic of old age. These alterations define the immunological age of individuals and are likely to participate to the decline of immune competence with HIV disease progression. It is therefore important to characterize these changes, which point toward the accumulation of highly differentiated immunocompetent cells, associated with overall telomere length shortening, as well as understanding their etiology, especially related to the impact of chronic immune activation. Particular attention should be given to the exhaustion of primary immune resources, including haematopoietic progenitors and naïve cells, which holds the key for effective hematopoiesis and immune response induction, respectively. The alteration of these compartments during HIV infection certainly represents the foundation of the immune parallel with aging.

Immune activation in prolonged cART-suppressed HIV patients is comparable to that of healthy controls

Sustained immune activation during chronic HIV infection is considered to augment co-morbidity and mortality. Effective combination antiretroviral therapy (cART) has shown to dampen immune activation especially during the first year cART, but the effects of long-term cART in patients without major comorbidities remains under-investigated. We performed a comprehensive analysis including cellular, intracellular and plasma biomarkers to study the effect of cART on immune parameters in 5 groups of 10 HIV patients. All patients were without major co-morbidities and grouped based on cART duration (0, 1, 3, 5, and 10 years). We included 10 matched healthy controls for comparison. Our data show that after the first year of cART, no additional effect on the level of inflammatory markers is observed in HIV infected patients without major co morbidities. Residual immune activation status in well-treated HIV-infection is similar to levels observed in healthy controls.

Integrative Analysis of Immunological Data to Explore Chronic Immune T-Cell Activation in Successfully Treated HIV Patients

OBJECTIVES

To unravel the complex relationships between cytomegalovirus-induced-, autoimmune-induced responses, microbial translocation and chronic immune activation (CIA) in successfully treated HIV-infected patients and to explore the mediating role of alpha-interferon in these processes.

DESIGN

Cross-sectional study nested in the ANRS CO3 Aquitaine Cohort, a prospective hospital-based cohort of HIV-1-infected patients in South-Western France.

METHODS

Patients initiated antiretroviral therapy between 2005 and 2008 and were treated with sustained virological suppression for at least two years. CIA was defined by the percentage of HLA-DR+/CD38+ among CD8+T-cells. Integrative analyses were performed using structural equation modelling (SEM).

RESULTS

The main analysis was performed in 57 HLA-A*0201 positive patients, due to availability of percentages of actin-, vimentin-, lamin-specific CD8+T-cells (HLA-A2-restricted tests) to further characterize autoimmune response. Cytomegalovirus-induced response was assessed by Quantiferon and pp-65 ELISPOT. SEM revealed a direct effect of cytomegalovirus-induced response on CIA (standardized estimate βstd = 0.56, p-value = 0.0004). The effect of autoimmune-induced response on CIA was indirect through alpha-interferon pathway, assessed by expression levels of 5 alpha-interferon-stimulated genes ADAR, ISG15, IFIT1, Mx1 and OAS1 (effect of autoimmune response on alpha-interferon: βstd = 0.36, p-value = 0.0401; effect of alpha-interferon on CIA: βstd = 0.39, p-value = 0.0044). There was no direct effect of autoimmune-induced response on CIA (p-value = 0.3169). Microbial translocation as measured by 16SrDNA and sCD14 in plasma was not associated with CIA. Results were consistent in 142 patients in whom cytomegalovirus and auto-immunity responses were measured by Quantiferon and anti-nuclear antibodies, respectively. All analyses performed in HLA-A*0201 positive patients and in the overall population revealed a significant effect of IFN-α latent variable on CIA.

CONCLUSION

The role of cytomegalovirus-induced response on CIA was confirmed as well as the involvement of alpha-interferon on CIA. The indirect effect of auto-immunity response on CIA revealed through the alpha-interferon pathway requires further investigation to confirm the potential role of auto-immunity for CIA in HIV-infected patients.

Serious Non-AIDS Events: Therapeutic Targets of Immune Activation and Chronic Inflammation in HIV Infection

In the antiretroviral therapy (ART) era, serious non-AIDS events (SNAEs) have become the major causes of morbidity and mortality in HIV-infected persons. Early ART initiation has the strongest evidence for reducing SNAEs and mortality. Biomarkers of immune activation, inflammation and coagulopathy do not fully normalize despite virologic suppression and persistent immune activation is an important contributor to SNAEs. A number of strategies aimed to reduce persistent immune activation including ART intensification to reduce residual viremia; treatment of co-infections to reduce chronic antigen stimulation; the use of anti-inflammatory agents, reducing microbial translocation as well as interventions to improve immune recovery through cytokine administration and reducing lymphoid tissue fibrosis, have been investigated. To date, there is little conclusive evidence on which strategies beyond treatment of hepatitis B and C co-infections and reducing cardiovascular risk factors will result in clinical benefits in patients already on ART with viral suppression. The use of statins seems to show early promise and larger clinical trials are underway to confirm their efficacy. At this stage, clinical care of HIV-infected patients should therefore focus on early diagnosis and prompt ART initiation, treatment of active co-infections and the aggressive management of co-morbidities until further data are available.

Dietary B Vitamins and Serum C-Reactive Protein in Persons With Human Immunodeficiency Virus Infection: The Positive Living With HIV (POLH) Study

BACKGROUND

B vitamins may have beneficial roles in reducing inflammation; however, research on the role of B vitamins in inflammation among HIV-infected persons is lacking.

OBJECTIVE

This study assessed the association between B vitamins and serum C-reactive protein (CRP) concentrations in HIV-infected persons.

METHODS

A cross-sectional survey was conducted among 314 HIV-infected persons (180 men and 134 women) aged 18 to 60 years residing in the Kathmandu, Nepal. High-sensitive and regular serum CRP concentrations were measured by the latex agglutination nephelometry and latex agglutination turbidimetric method, respectively. Dietary intake was assessed using 2 nonconsecutive 24-hour dietary recalls. The relationships between B vitamins and serum CRP concentrations were assessed using multiple regression analysis.

RESULTS

The multivariate-adjusted geometric mean of serum CRP concentrations was significantly decreased with an increasing B vitamins intake across quartiles of niacin (P for trend = .007), pyridoxine (P for trend = .042), and cobalamin (P for trend = .037) in men. In men, the mean serum CRP concentrations in the highest quartiles of niacin, pyridoxine, and cobalamin were 63%, 38%, and 58%, respectively, lower than that in the lowest quartile. In women, the mean serum CRP concentrations in the highest quartiles of riboflavin (P for trend = .084) and pyridoxine (P for trend = .093) were 37% and 47%, respectively, lower than that in the lowest quartile.

CONCLUSION

High intake of niacin, pyridoxine, or cobalamin was independently associated with decreased serum CRP concentrations among HIV-infected men. Further prospective studies are warranted to confirm the role of B vitamins in inflammation among HIV-infected persons.

Serum Zinc Concentration and C-Reactive Protein in Individuals with Human Immunodeficiency Virus Infection: the Positive Living with HIV (POLH) Study

Low zinc levels and chronic inflammation are common in individuals infected with human immunodeficiency virus (HIV). Zinc deficiency may promote systemic inflammation, but research on the role of zinc in inflammation among HIV-positive individuals taking account of anti-retroviral therapy is lacking. We assessed the association between serum zinc and C-reactive protein (CRP) concentration in a cohort of HIV-positive individuals. A cross-sectional survey was conducted among 311 HIV-positive individuals (177 men and 134 women) aged 18-60 years residing in Kathmandu, Nepal. High-sensitive or regular serum CRP concentrations were measured by the latex agglutination nephelometry or turbidimetric method, and zinc concentrations were measured by the atomic absorption method. Relationships were assessed using multiple linear regression analysis. The geometric means of zinc in men and women were 73.83 and 71.93 ug/dL, respectively, and of CRP were 1.64 and 0.96 mg/L, respectively. Mean serum CRP concentration was significantly decreased with increasing serum zinc concentration across zinc tertiles (P for trend = 0.010), with mean serum CRP concentration in the highest tertile of serum zinc concentration was 44.2 % lower than that in the lowest tertile. The mean serum CRP concentrations in men and women in the highest tertile of serum zinc concentrations were 30 and 35.9 % lower, respectively, than that in the lowest tertile (P for trend = 0.263 and 0.162, respectively). We found a significant inverse relation between log zinc and log CRP concentrations (beta for 1 unit change in log zinc; β = -1.79, p = 0.0003). Serum zinc concentration may be inversely associated with serum CRP concentration in HIV-positive individuals.

T-cell activation is an immune correlate of risk in BCG vaccinated infants

Vaccines to protect against tuberculosis (TB) are urgently needed. We performed a case-control analysis to identify immune correlates of TB disease risk in Bacille Calmette-Guerin (BCG) immunized infants from the MVA85A efficacy trial. Among 53 TB case infants and 205 matched controls, the frequency of activated HLA-DR(+) CD4(+) T cells associates with increased TB disease risk (OR=1.828, 95% CI=1.25-2.68, P=0.002, FDR=0.04, conditional logistic regression). In an independent study of Mycobacterium tuberculosis-infected adolescents, activated HLA-DR(+) CD4(+) T cells also associate with increased TB disease risk (OR=1.387, 95% CI=1.068-1.801, P=0.014, conditional logistic regression). In infants, BCG-specific T cells secreting IFN-γ associate with reduced risk of TB (OR=0.502, 95% CI=0.29-0.86, P=0.013, FDR=0.14). The causes and impact of T-cell activation on disease risk should be considered when designing and testing TB vaccine candidates for these populations.

Association of CMV, HBV, or HCV co-infection with vaccine response in adults with well-controlled HIV infection

Even after CD4 count recovery on antiretroviral therapy, HIV infection is associated with decreased response to most vaccines compared to the general population. Chronic infections with viruses such as cytomegalovirus (CMV), hepatitis B virus (HBV), and hepatitis C virus (HCV), which are more prevalent in HIV-infected populations, have been linked to immune dysfunction and decreased vaccine response in the general population. However, whether co-infection with these other viruses contributes to the decreased vaccine response seen in adults with well-controlled HIV infection is unknown. We conducted a secondary analysis of data and serum from adults with well-controlled HIV infection from an inactivated polio vaccine trial (224 subjects) and a pneumococcal conjugate vaccine study (128 subjects). We evaluated the association of CMV, HBV, or HCV co-infection with post-vaccination antibody levels using both univariate and multivariate analyses, controlling for factors such as age, race, CD4 count, comorbidities, smoking status, and baseline antibody levels. Ninety-three percent, 7%, and 14% of subjects were co-infected with CMV, HBV, and HCV respectively. On both univariate and multivariate analysis, neither CMV nor HCV co-infection were significantly associated with post-vaccination antibody levels to either vaccine. HBV co-infection was significantly associated with post-vaccination antibody concentrations for pneumococcal serotype 7F on univariate analysis and 6A on multivariate analysis, but the association was with higher antibody concentrations. In conclusion, co-infection with CMV, HBV, or HCV does not appear to contribute to the decreased vaccine response seen in adults with well-controlled HIV infection.

Higher Activation in CD4(+) T Cells But Similar Viral Control Among HIV/Hepatitis C Virus-Coinfected Patients on a Simplification Monotherapy

The aim of this study was to assess whether hepatitis C virus (HCV) coinfection would affect the clinical and immunological outcome of HIV-infected patients following a simplification strategy. A prospective cohort of HIV-infected patients starting a ritonavir boosted darunavir monotherapy (mtDRV/rtv) was followed for 24 months. HCV infection was evaluated by HCV viremia and hepatic fibrosis. Immune activation was studied as HLA-DR CD38 coexpression on CD4(+) and CD8(+) T cells and also the quantification of plasma sCD14 levels. Microbial translocation was studied by the plasma levels of 16S rDNA and lipopolysaccharide (LPS). A total of 150 HIV-infected patients were enrolled in this study, including 46 individuals also infected with HCV (30.6%). HIV/HCV coinfection did not decrease mtDRV/rtv efficacy, since similar rates of HIV-1 intermittent viremia (HCV: 26.6% vs. no-HCV: 34.7%) and episodes of virological failure (HCV: 22.2% vs. no-HCV: 11.2%, p-value = 0.381) were found. No major differences were found between both groups at baseline, although higher HLA-DR(+)CD38(+)CD4(+) T cell counts were found in the coinfected group (HCV: 6.65% vs. no-HCV: 4.55%, p-value = 0.032); this difference was maintained in the 24 months of follow-up. After the 24-month follow-up, both groups, HIV-monoinfected patients and HIV/HCV-coinfected patients, presented similar immune activation and microbial translocation profiles. In conclusion, the use of a simplified mtDRV/rtv strategy compromises neither HIV nor HCV viremic control in coinfected patients, although a higher immune activation of CD4(+) T cells was found.

Association of immune-activation and senescence markers with non-AIDS-defining comorbidities in HIV-suppressed patients

OBJECTIVES

We studied the link between T-cell activation, differentiation and senescence phenotypes and non-AIDS-related comorbidities in HIV-suppressed patients.

DESIGN

Patients included in the ANRS CO3 Aquitaine Cohort were consecutively enrolled in this cross-sectional study between October 2011 and May 2013 called Chronic Immune Activation and Senescence (CIADIS) study.

METHODS

We summarized immune markers [CD4 and CD8 activation (DR), differentiation (naive and terminally differentiated memory T cells), and senescence (CD57CD28)] in a weighted immune score by principal component analysis called CIADIS. Previously described Veterans Aging Cohort Study (VACS) index and immune risk profile (IRP) scores were calculated. We used adjusted logistic regression to assess the association between the CIADIS score and the presence of at least three non-AIDS-defining comorbidities.

RESULTS

Of 876 patients with an undetectable viral load, 73.4% were men and median age was 50.5 years [interquartile range (IQR) 44.7-56.7 years]. Median CD4 T-cell count was 579/μl (IQR 429-759 cells/μl), and median duration of HIV viral suppression was 5.3 years (IQR 2.3-8.7). The weighted CIADIS score was associated with at least three comorbidities (odds ratio 1.3 for 1 SD more, 95% confidence interval 1.0, 1.6) independently of age, sex, AIDS stage, and the Veterans Aging Cohort Study score. The CIADIS and the immune risk profile scores were significantly associated with at least three comorbidities in adjusted models restricted to patients younger than 60 years. None of the tested scores were associated with at least three comorbidities in patients older than 60 years.

CONCLUSIONS

The weighted CIADIS score based on activation, senescence, and differentiation markers might help physicians identifying patients at a higher risk for non-AIDS-related comorbidities.

Probiotics Reduce Inflammation in Antiretroviral Treated, HIV-Infected Individuals: Results of the "Probio-HIV" Clinical Trial

Background

HIV infection results in damage to the gastrointestinal (GI) tract, microbial translocation and immune activation. These are not completely normalized with combined antiretroviral therapy (cART). Moreover, increate morbidity and mortality of cART-treated HIV-infected individuals is associated with inflammation.

Methods

In order to enhance GI tract immunity, we recruited and treated 20 HIV-infected humans with cART supplemented with probiotics and followed inflammation and immunological parameters (clinical trial number NCT02164344). 11 HIV seronegative subjects were included as control group. The enumeration of CD4+, CD8+, CD38+ and HLA-DR+ lymphocytes were evaluated on peripheral blood; HIV-RNA levels, sCD14, d-dimer, C-reactive protein (CRP) high sensitivity C-reactive protein (hsCRP), IL-6 and Lipopolysaccharide Binding Protein (LBP) were assayed on plasma.

Results

We observe that cART does not normalize the levels of immune activation in HIV positive patients anyway inflammation and markers of microbial translocation were significantly reduced with probiotic supplementation. Patients show a clear and statistically significant reduction in the levels of immune activation on CD4 T-lymphocytes, for both markers CD38 and HLA-DR and their simultaneous expression, LBP and hsCRP plasma levels after probiotic diet supplementation settling to values comparable to controls.

Conclusions

Supplementing cART with probiotics in HIV-infected individuals may improve GI tract immunity and there by mitigate inflammatory sequelae, ultimately improving prognosis.

Trial Registration

ClinicalTrials.gov NCT02164344

Association of CMV-Specific T Cell-Mediated Immunity with CMV DNAemia and Development of CMV Disease in HIV-1-Infected Individuals

BACKGROUND

Among HIV-1-infected individuals, cytomegalovirus (CMV) reactivation and disease occur in the setting of advanced immunosuppression. The value of a standardized assessment of CMV-specific T-cell mediated immunity by the CMV QuantiFERON assay (CMV-QFT) has not yet been thoroughly investigated in HIV-1-infected subjects.

METHODS

Prospective, longitudinal study in 153 HIV-1-infected subjects with a CD4+ T cell count < 350/μL who simultaneously underwent CMV-QFT, CMV serology testing and CMV-DNA quantification. Factors associated with CMV-QFT were evaluated. Clinical screening for CMV manifestations was then performed every 3 months.

RESULTS

Among the 141 CMV IgG-seropositive individuals the CMV-QFT assay yielded reactive results in 84% (118/141), negative results in 15% (21/141) and indeterminate (negative mitogen IFN-gamma response) results in 1% (2/141) of subjects. The mean actual CD4+ T cell count was significantly higher in CMV-QFT reactive subjects, when compared to CMV-QFT non-reactive individuals (183 ± 102 vs. 126 ± 104 cells/μL, P = 0.015). A significantly lower proportion of CMV-QFT reactive vs. non-reactive patients displayed CMV DNAemia > 100 copies/mL (23% (27/118) vs. 48% (11/23), P = 0.02). Furthermore, a statistically significant inverse association between mitogen IFN-gamma response and CMV-DNAemia > 1000 copies/mL was observed (P < 0.001). During the observational period, 5 CMV end-organ manifestations were observed. In three of the CMV cases the CMV-QFT yielded indeterminate results.

CONCLUSIONS

While CMV-QFT reactivity indicates CMV-specific immunity, indeterminate results due to negative mitogen IFN-gamma response might reflect HIV-1-induced immunodeficiency. Thus, dependency upon CD4+ T cell count should be considered when interpreting CMV-QFT results.

Differential effects of viremia and microbial translocation on immune activation in HIV-infected patients throughout ritonavir-boosted darunavir monotherapy

The purpose of this article is to evaluate the evolution of microbial translocation (MT) and its role in CD4 and CD8 T cells immune activation (IA) in HIV-1-infected patients on ritonavir-boosted darunavir monotherapy (mtDRV/rtv).Prospective study of consecutive HIV-1-infected patients switched to mtDRV/rtv as a simplification regimen. Subjects were classified according to the virological behavior during a 24-month follow-up as continuous undetectable viral load, blips, intermittent viremia, and virological failure (VF). MT was evaluated by plasma LPS and 16S genomic rDNA (16S rDNA) levels, whereas IA was assessed by the coexpression of HLA-DR and CD38 in CD4 and CD8 T cells, and plasma sCD14 levels.Seventy-one patients were included in this substudy of the MonDar cohort (ClinicalTrials.gov: NCT01505722). At baseline, CD4 (ρ = -0.352, P = 0.01) and CD8 T-cell activation (ρ = -0.468, P < 0.001) were correlated with time with viral suppression, but not with MT markers. A significant decrease in plasma LPS levels was found only in patients without VF (baseline, 77.8 vs month 24, 60.4 pg/mL; P < 0.001]. Both plasma 16S rDNA and sCD14 levels were unchanged irrespective of the viral behavior. The only variable independently associated with a decrease in CD4 and CD8 T cells activation was an undetectable HIV-1 viremia (β = 4.78, P < 0.001 and β = 2.93, P = 0.005, respectively).MT does not have a pivotal role in T-cell activation, at least in patients with long-term viral suppression. The viremic episodes and VF are the main factors related to CD4 and CD8 T-cells IA, even during mtDRV/rtv.

An NK Cell Population Lacking FcRγ Is Expanded in Chronically Infected HIV Patients

We previously demonstrated that NK cells from HIV-infected individuals have elevated expression of activation markers, spontaneously degranulate ex vivo, and decrease expression of a signal-transducing protein for NK-activating receptors, FcRγ. Importantly, these changes were maintained in virologically suppressed (VS) individuals receiving combination antiretroviral therapy (cART). In this study, we show that loss of FcRγ is caused by the expansion of a novel subset of FcRγ(-)CD56(dim) NK cells with an altered activation receptor repertoire and biological properties. In a cross-sectional study, FcRγ(-) NK cells as a proportion of total CD56(dim) NK cells increased in cART-naive viremic HIV-infected individuals (median [interquartile range] = 25.9 [12.6-56.1] compared with 3.80 [1.15-11.5] for HIV(-) controls, p < 0.0001) and in VS HIV-infected individuals (22.7 [13.1-56.2] compared with 3.80 [1.15-11.5], p = 0.0004), with no difference between cART-naive and VS patients (p = 0.93). FcRγ(-) NK cells expressed no NKp30 or NKp46. They showed greater Ab-dependent cellular cytotoxicity activity against rituximab-opsonized Raji cells and in a whole-blood assay measuring NK responses to overlapping HIV peptides, despite having reduced CD16 expression compared with conventional NK cells. Their prevalence correlated with CMV Ab titers in HIV(-) subjects but not in HIV(+) individuals, and with the inflammatory marker CXCL10 in both groups. The expansion of a subset of NK cells that lacks NKp30 and NKp46 to ∼90% of CD56(dim) NK cells in some VS HIV(+) individuals may influence NK-mediated immunosurveillance in patients receiving cART.

No differences of immune activation and microbial translocation among HIV-infected children receiving combined antiretroviral therapy or protease inhibitor monotherapy

This is a cross-sectional study of 15 aviremic chronic HIV-infected children revealing no differences in immune activation (IA; HLA-DRCD38 CD4 and CD8 T cells, and sCD14) and microbial translocation (MT; lipopolysaccharides (LPS) and 16S rDNA) among HIV-infected patients under combined antiretroviral treatment (cART; n = 10) or ritonavir-boosted protease inhibitor monotherapy (mtPI/rtv; n = 5). In both cases, IA and MT were lower in healthy control children (n = 32). This observational study suggests that ritonavir boosted protease inhibitor monotherapy (mtPI/rtv) is not associated with an increased state of IA or MT as compared with children receiving cART.

Immune resilience in HIV-infected individuals seronegative for cytomegalovirus

OBJECTIVE

Low CD4/CD8 T-cell ratios occur in conditions associated with reduced immune resilience, including older age and HIV infection. Effective antiretroviral therapy increases CD4/CD8 T-cell ratios, but often not to preinfection levels. The reasons for this deficit remain unclear. As cytomegalovirus (CMV) infection exacerbates falling CD4/CD8 T-cell ratios and immune senescence in the old elderly population, we investigated whether CMV infection is associated with refractory inversion of CD4/CD8 T-cell ratios and increased phenotypic evidence of immune senescence in HIV infection.

DESIGN

An observational cohort study of HIV-infected individuals attending the Newfoundland and Labrador Provincial HIV Clinic in St. John's.

METHODS

CMV infection status was determined by ELISA with infected cell lysate. Expression of CD28 and CD57 on CD8 T cells and cellular immune responses against CMV were measured by flow cytometry. We compared CD4/CD8 T-cell ratios, percentage of CD8 T cells expressing CD28 and percentage of CD8 T cells expressing CD57 between groups of HIV-infected persons discordant for CMV infection.

RESULTS

The CMV-seronegative group had significantly higher CD4/CD8 T-cell ratios, more frequent normalization of the ratio to at least 1, and lesser phenotypic evidence of immune senescence.

CONCLUSION

CMV infection is associated with reduced immune reconstitution in HIV infection, even with suppression of HIV replication below detectable levels. This suggests that CMV infection, or some related factor, influences immune resilience in the setting of HIV infection.

γδ T cells are involved in acute HIV infection and associated with AIDS progression

Background

Early diagnosis is vital to HIV control. γδ T cells play critical roles in viral infections, but their activation in acute HIV infected patients and follow up to 18 months has not been described.

Methods

Changes in γδ T cells, including subsets, function and activation, in treated and untreated acutely HIV-infected patients (n = 79) were compared by cytotoxicity assay and flow cytometry with healthy controls (n = 21) at month 0, 6, 12 and 18.

Results

In acutely HIV-infected patients, Vδ1 cell proportion was elevated (P = 0.027) with Vδ2 population reduced (P = 0.002). Effector and central memory γδ T cell factions were decreased (P = 0.006 and P = 0.001, respectively), while proportion of terminal γδ T cells increased (P = 0.002). γδ T cell cytotoxicity was compromised over time. Fraction of IL-17-producing cells increased (P = 0.008), and IFN-γ-producing cells were unaffected (P = 0.115). Elevation of a microbial translocation marker, sCD14, was associated with γδ T cell activation (P = 0.001), which increased in a time-dependent manner, correlating with CD4/CD8 T cell activation set-points and CD4 counts. Antiretroviral therapy did not affect these changes.

Conclusions

γδ T cell subpopulation and functions change significantly in acute HIV infection and over time. Early γδ T cell activation was associated with CD4/CD8 T cell activation set-points, which predict AIDS progression. Therefore, γδ T cell activation represents a potential surrogate marker of AIDS progression.

Microbial translocation and T cell activation are not associated in chronic HIV-infected children

A cross-sectional study of 77 chronic HIV-infected children revealed higher levels of biomarkers of inflammation (ultrasensitive C-reactive protein, D-dimer and β-2-microglobulin), immune activation (HLA-DR+ CD38+ CD4+ and CD8+ T cells) and microbial translocation [lipopolysaccaride (LPS), microbial 16S rDNA and sCD14] than 32 healthy controls. Immune activation was higher in viremic children, but microbial translocation occurred independently of viraemia and T cell activation. Our results do not support a relevant role of microbial translocation in T cell activation in chronic HIV-infected children, proposing a need to develop strategies to minimize microbial translocation in the future.

Quantification of cytomegalovirus viral load

Cytomegalovirus (CMV), a member of the Herpesviridae family, is worldwide distributed. After the primary infection, CMV induces a latent infection with possible reactivation(s). It is responsible for severe to life-threatening diseases in immunocompromised patients and in foetuses and newborns of infected mothers. For monitoring CMV load, classical techniques based on rapid culture or pp65 antigenemia are progressively replaced by quantitative nuclear acid tests (QNAT), easier to implement and standardize. A large variety of QNAT are available from laboratory-developed assays to fully-automated commercial tests. The indications of CMV quantification include CMV infection during pregnancy and in newborns, and viral surveillance of grafted and non-grafted immunocompromised patients, patients with bowel inflammatory diseases and those hospitalised in intensive care unit. A close cooperation between virologists and clinicians is essential for optimizing the benefit of CMV DNA monitoring.