Inflammatory co-morbidities in HIV+ individuals: learning lessons from healthy ageing

Persistence of a Skewed Repertoire of NK Cells in People with HIV-1 on Long-Term Antiretroviral Therapy

HIV-1 infection greatly alters the NK cell phenotypic and functional repertoire. This is highlighted by the expansion of a rare population of FcRγ- NK cells exhibiting characteristics of traditional immunologic memory in people with HIV (PWH). Although current antiretroviral therapy (ART) effectively controls HIV-1 viremia and disease progression, its impact on HIV-1-associated NK cell abnormalities remains unclear. To address this, we performed a longitudinal analysis detailing conventional and memory-like NK cell characteristics in n = 60 PWH during the first 4 y of ART. Throughout this regimen, a skewed repertoire of cytokine unresponsive FcRγ- memory-like NK cells persisted and accompanied an overall increase in NK surface expression of CD57 and KLRG1, suggestive of progression toward immune senescence. These traits were linked to elevated serum inflammatory biomarkers and increasing Ab titers to human CMV, with human CMV viremia detected in approximately one-third of PWH at years 1-4 of ART. Interestingly, 40% of PWH displayed atypical NK cell subsets, representing intermediate stages of NK-poiesis based on single-cell multiomic trajectory analysis. Our findings indicate that NK cell irregularities persist in PWH despite long-term ART, underscoring the need to better understand the causative mechanisms that prevent full restoration of immune health in PWH.

Injecting drug use and hepatitis C virus infection independently increase biomarkers of inflammatory disease risk which are incompletely restored by curative direct-acting antiviral therapy

Background

Hepatitis C virus (HCV) infections are more prevalent in people who inject drugs (PWID) who often experience additional health risks. HCV induces inflammation and immune alterations that contribute to hepatic and non-hepatic morbidities. It remains unclear whether curative direct acting antiviral (DAA) therapy completely reverses immune alterations in PWID.

Methods

Plasma biomarkers of immune activation associated with chronic disease risk were measured in HCV-seronegative (n=24) and HCV RNA+ (n=32) PWID at baseline and longitudinally after DAA therapy. Adjusted generalised estimating equations were used to assess longitudinal changes in biomarker levels. Comparisons between community controls (n=29) and HCV-seronegative PWID were made using adjusted multiple regression modelling.

Results

HCV-seronegative PWID exhibited significantly increased levels of inflammatory biomarkers including soluble (s) TNF-RII, IL-6, sCD14 and sCD163 and the diabetes index HbA1c as compared to community controls. CXCL10, sTNF-RII, vascular cell adhesion molecule-1 and lipopolysaccharide binding protein (LBP) were additionally elevated in PWID with viremic HCV infection as compared to HCV- PWID. Whilst curative DAA therapy reversed some biomarkers, others including LBP and sTNF-RII remained elevated 48 weeks after HCV cure.

Conclusion

Elevated levels of inflammatory and chronic disease biomarkers in PWID suggest an increased risk of chronic morbidities such as diabetes and cardiovascular disease. HCV infection in PWID poses an additional disease burden, amplified by the incomplete reversal of immune dysfunction following DAA therapy. These findings highlight the need for heightened clinical surveillance of PWID for chronic inflammatory diseases, particularly those with a history of HCV infection.

Mapping the interplay between NK cells and HIV: therapeutic implications

Although highly effective at durably suppressing plasma HIV-1 viremia, combination antiretroviral therapy (ART) treatment regimens do not eradicate the virus, which persists in long-lived CD4+ T cells. This latent viral reservoir serves as a source of plasma viral rebound following treatment interruption, thus requiring lifelong adherence to ART. Additionally, challenges remain related not only to access to therapy but also to a higher prevalence of comorbidities with an inflammatory etiology in treated HIV-1+ individuals, underscoring the need to explore therapeutic alternatives that achieve sustained virologic remission in the absence of ART. Natural killer (NK) cells are uniquely positioned to positively impact antiviral immunity, in part due to the pleiotropic nature of their effector functions, including the acquisition of memory-like features, and, therefore, hold great promise for transforming HIV-1 therapeutic modalities. In addition to defining the ability of NK cells to contribute to HIV-1 control, this review provides a basic immunologic understanding of the impact of HIV-1 infection and ART on the phenotypic and functional character of NK cells. We further delineate the qualities of "memory" NK cell populations, as well as the impact of HCMV on their induction and subsequent expansion in HIV-1 infection. We conclude by highlighting promising avenues for optimizing NK cell responses to improve HIV-1 control and effect a functional cure, including blockade of inhibitory NK receptors, TLR agonists to promote latency reversal and NK cell activation, CAR NK cells, BiKEs/TriKEs, and the role of HIV-1-specific bNAbs in NK cell-mediated ADCC activity against HIV-1-infected cells.

Alterations in circulating markers in HIV/AIDS patients with poor immune reconstitution: Novel insights from microbial translocation and innate immunity

After long-term anti-retroviral therapy (ART) treatment, most human immunodeficiency virus (HIV)/Acquired Immure Deficiency Syndrome (AIDS) patients can achieve virological suppression and gradual recovery of CD4⁺ T-lymphocyte (CD4⁺ T cell) counts. However, some patients still fail to attain normal CD4⁺ T cell counts; this group of patients are called immune non-responders (INRs), and these patients show severe immune dysfunction. The potential mechanism of poor immune reconstitution (PIR) remains unclear and the identification of uniform biomarkers to predict the occurrence of PIR is particularly vital. But limited information is available on the relationship between circulating markers of INRs and immune recovery. Hence, this review summarises alterations in the intestine microbiota and associated markers in the setting of PIR to better understand host-microbiota-metabolite interactions in HIV immune reconstitution and to identify biomarkers that can predict recovery of CD4⁺ T cell counts in INRs.

CD4/CD8 Ratio and Cancer Risk Among Adults With HIV

BACKGROUND

Independent of CD4 cell count, a low CD4/CD8 ratio in people with HIV (PWH) is associated with deleterious immune senescence, activation, and inflammation, which may contribute to carcinogenesis and excess cancer risk. We examined whether low CD4/CD8 ratios predicted cancer among PWH in the United States and Canada.

METHODS

We examined all cancer-free PWH with 1 or more CD4/CD8 values from North American AIDS Cohort Collaboration on Research and Design observational cohorts with validated cancer diagnoses between 1998 and 2016. We evaluated the association between time-lagged CD4/CD8 ratio and risk of specific cancers in multivariable, time-updated Cox proportional hazard models using restricted cubic spines. Models were adjusted for age, sex, race and ethnicity, hepatitis C virus, and time-updated CD4 cell count, HIV RNA, and history of AIDS-defining illness.

RESULTS

Among 83 893 PWH, there were 5628 incident cancers, including lung cancer (n = 755), Kaposi sarcoma (n = 501), non-Hodgkin lymphoma (n = 497), and anal cancer (n = 439). The median age at cohort entry was 43 years. The overall median 6-month lagged CD4/CD8 ratio was 0.52 (interquartile range = 0.30-0.82). Compared with a 6-month lagged CD4/CD8 of 0.80, a CD4/CD8 of 0.30 was associated with increased risk of any incident cancer (adjusted hazard ratio = 1.24 [95% confidence interval = 1.14 to 1.35]). The CD4/CD8 ratio was also inversely associated with non-Hodgkin lymphoma, Kaposi sarcoma, lung cancer, anal cancer, and colorectal cancer in adjusted analyses (all 2-sided P < .05). Results were similar using 12-, 18-, and 24-month lagged CD4/CD8 values.

CONCLUSIONS

A low CD4/CD8 ratio up to 24 months before cancer diagnosis was independently associated with increased cancer risk in PWH and may serve as a clinical biomarker.

Clinical perspectives on the age-related increase of immunosuppressive activity

The aging process is associated with a remodeling of the immune system involving chronic low-grade inflammation and a gradual decline in the function of the immune system. These processes are also called inflammaging and immunosenescence. The age-related immune remodeling is associated with many clinical changes, e.g., risk for cancers and chronic infections increases, whereas the efficiency of vaccination and immunotherapy declines with aging. On the other hand, there is convincing evidence that chronic inflammatory states promote the premature aging process. The inflammation associated with aging or chronic inflammatory conditions stimulates a counteracting immunosuppression which protects tissues from excessive inflammatory injuries but promotes immunosenescence. Immunosuppression is a driving force in tumors and chronic infections and it also induces the tolerance to vaccination and immunotherapies. Immunosuppressive cells, e.g., myeloid-derived suppressor cells (MDSC), regulatory T cells (Treg), and type M2 macrophages, have a crucial role in tumorigenesis and chronic infections as well as in the tolerance to vaccination and immunotherapies. Interestingly, there is substantial evidence that inflammaging is also associated with an increased immunosuppressive activity, e.g., upregulation of immunosuppressive cells and anti-inflammatory cytokines. Given that both the aging and chronic inflammatory states involve the activation of immunosuppression and immunosenescence, this might explain why aging is a risk factor for tumorigenesis and chronic inflammatory states and conversely, chronic inflammatory insults promote the premature aging process in humans.

A Sex-Stratified Analysis of Monocyte Phenotypes Associated with HIV Infection in Uganda

Women with HIV may experience higher rates of non-AIDS comorbidities compared to men with HIV, but the underlying mechanisms are not well understood. We investigated sex-related differences in the effects of HIV on monocyte phenotypes within the Ugandan Study of HIV effects on the Myocardium and Atherosclerosis (mUTIMA). Of 133 participants who provided blood for flow cytometry assays, 86 (65%) were women and 91 (68%) were persons living with HIV (PLWH) on antiretroviral therapy. The median age was 57 (interquartile range, 52–63) years. PLWH exhibited a lower proportion of circulating CD14⁺CD16^- classical monocytes (66.3% vs. 75.1%; p < 0.001), and higher proportion of CD14⁺CD16⁺ inflammatory monocytes (17% vs. 11.7%; p = 0.005) compared to HIV-uninfected participants. PLWH had an increased expression of the chemokine receptor CX3CR1 in total monocytes (CX3CR1⁺ monocytes, 24.5% vs. 4.7%; p < 0.001) and monocyte subsets. These findings were generally similar when analyzed by sex, with no significant interactions between sex and HIV status in adjusted models. Our data show that the inflammatory monocyte subset is expanded and monocyte CX3CR1 chemokine receptor expression is enhanced among PLWH, regardless of sex. Whether these parameters differentially affect risk for non-AIDS comorbidities and clinical outcomes in women with HIV requires additional investigation.

Epigenetic Features of HIV-Induced T-Cell Exhaustion Persist Despite Early Antiretroviral Therapy

T cell dysfunction occurs early following HIV infection, impacting the emergence of non-AIDS morbidities and limiting curative efforts. ART initiated during primary HIV infection (PHI) can reverse this dysfunction, but the extent of recovery is unknown. We studied 66 HIV-infected individuals treated from early PHI with up to three years of ART. Compared with HIV-uninfected controls, CD4 and CD8 T cells from early HIV infection were characterised by T cell activation and increased expression of the immune checkpoint receptors (ICRs) PD1, Tim-3 and TIGIT. Three years of ART lead to partial – but not complete – normalisation of ICR expression, the dynamics of which varied for individual ICRs. For HIV-specific cells, epigenetic profiling of tetramer-sorted CD8 T cells revealed that epigenetic features of exhaustion typically seen in chronic HIV infection were already present early in PHI, and that ART initiation during PHI resulted in only a partial shift of the epigenome to one with more favourable memory characteristics. These findings suggest that although ART initiation during PHI results in significant immune reconstitution, there may be only partial resolution of HIV-related phenotypic and epigenetic changes.

Immune activation and chronic inflammation: Is there an additional effect of HIV in a geriatric population?

ABSTRACT

HIV infection has become a chronic disease, with a lower mortality, but a consequent increase in age-related noninfectious comorbidities. Metabolic disorders have been linked to the effect of cART as well to the effects of immune activation and chronic inflammation. Whereas it is known that aging is intrinsically associated with hyperinflammation and immune system deterioration, the relative impact of chronic HIV infection on such inflammatory and immune activation has not yet been studied focusing on an elderly HIV-infected population.The objectives of the study were to assess 29 blood markers of immune activation and inflammation using an ultrasensitive technique, in HIV-infected patients aged ≥75 years with no or 1 comorbidity (among hypertension, renal disease, neoplasia, diabetes mellitus, cardiovascular disease, stroke, dyslipidemia, and osteoporosis), in comparison with age-adjusted HIV-uninfected individuals to identify whether biomarkers were associated with comorbidities. Wilcoxon nonparametric tests were used to compare the levels of each marker between control and HIV groups; logistic regression to identify biomarkers associated to comorbidity in the HIV group and principal component analysis (PCA) to determine clusters associated with a group or a specific comorbidity.A total of 111 HIV-infected subjects were included from the Dat'AIDS cohort and compared to 63 HIV-uninfected controls. In the HIV-infected group, 4 biomarkers were associated with the risk of developing a comorbidity: monocyte chemoattractant protein-1 (MCP-1), neurofilament light chain (NF-L), neopterin, and soluble CD14. Six biomarkers (interleukin [IL]-1B, IL-7, IL-18, neopterin, sCD14, and fatty acid-binding protein) were significantly higher in the HIV-infected group compared to the control group, 11 biomarkers (myeloperoxydase, interleukin-1 receptor antagonist, tumor necrosis factor receptor 1, interferon-gamma, MCP-1, tumor necrosis factor receptor 2, IL-22, ultra sensitivity C-reactive protein, fibrinogen, IL-6, and NF-L) were lower. Despite those differences, PCA to determine clusters associated with a group or a specific comorbidity did not reveal clustering nor between healthy control and HIV-infected patients neither between the presence of comorbidity within HIV-infected group.In this highly selected geriatric HIV population, HIV infection does not seem to have an additional impact on age-related inflammation and immune disorder. Close monitoring could have led to optimize prevention and treatment of comorbidities, and have limited both immune activation and inflammation in the aging HIV population.

IL-18 Responsiveness Defines Limitations in Immune Help for Specialized FcRγ- NK Cells

Despite being prolific innate killers, NK cells are also key helper cells in antiviral defense, influencing adaptive immune responses via interactions with dendritic cells (DCs). In addition to causing NK cell dysfunction, HIV-1 infection contributes to the expansion of a rare population of NK cells deficient in FcRγ (FcRγ^-), an intracellular adaptor protein that associates with CD16. The implications of this inflated NK cell subset in treated HIV-1 infection remain unclear. In this study, we explored the helper function of human NK cells in chronic HIV-1 infection, with a particular focus on characterizing FcRγ^- NK cells. Exposure of NK cells to innate DC-derived costimulatory factors triggered their helper activity, defined by their ability to produce IFN-γ and to drive the maturation of high IL-12-producing DCs. In this setting, however, FcRγ^- NK cells were defective at producing the dominant DC-polarizing agent IFN-γ. The reduced responsiveness of FcRγ^- NK cells to IL-18 in particular, which was attributable to impaired inducible expression of IL-18Rα, extended beyond an inability to produce IFN-γ, as FcRγ^- NK cells showed limited potential to differentiate into CD16^-/CD25⁺/CD83⁺ helper cells. Notwithstanding their deficiencies in responsiveness to innate environmental cues, FcRγ^- NK cells responded robustly to adaptive Ab-mediated signaling through CD16. The presence of an expanded population of FcRγ^- NK cells with a diminished capacity to respond to IL-18 and to effectively modulate DC function may contribute to disturbances in proper immune homeostasis associated with HIV-1 infection and to defects in the initiation of optimal adaptive antiviral responses.

Physical activity levels among Malawian adults living with HIV and receiving anti-retroviral therapy

Introduction

Despite increasing life expectancy among people living with HIV (PLWHIV), anti-retroviral therapy (ART) side effects, HIV chronic inflammation and co-morbidities may limit functional abilities and reduced participation in exercises and physical activity (PA). PA improves wellbeing and overall quality of life of PLWHIV. In Malawi, there is paucity of information regarding PA levels among Malawians living with HIV and receiving ART. Therefore, this study aimed at determining PA levels among PLWHIV and receiving ART in Malawi.

Methods

A quantitative cross-sectional design was employed. Eligible participants were male and female adults aged 18–45 years living with HIV receiving ART for at least 1 year. The participants were recruited from Limbe Health Center, Gateway Health Center and Queen Elizabeth Central Hospital (QECH) in Blantyre, Malawi. The International Physical Activity Questionnaire (IPAQ) was used to assess the PA levels. A Stadiometer (HS-DBS00361, Model: 1127154) was used to measure weight (kg) and height (cm) of the participants.

Results

A total of 213 participants were recruited. There were more females than male participants (n=132 females). Overall, the mean age of all participants was 37±6.5 years and they were within normal body weight (BMI=23±4.0). Many participants (n=85, 40%) had low PA levels followed by those who were moderately physically active (n=75, 36%). A larger proportion of the female participants (51%) had low PA levels compared to males (22%). Forty-two percent of participants with 1–3 years of ART had low PA whereas 39% with >3 years ART had low PA.

Conclusion

Most PLWHIV and receiving ART in the sample have low PA levels. The study has also revealed that proportionally more females than males had low PA levels.

Contribution of the Microbiota to Intestinal Homeostasis and its Role in the Pathogenesis of HIV-1 Infection

During HIV infection, massive destruction of CD4+ T cells ensues, preferentially depleting the Th17 subset at the gut-associated lymphoid tissue (GALT), leading to a loss of mucosal integrity and an increase in cell permeability. This process favors microbial translocation between the intestinal lumen and the circulatory system, contributing to persistent immune activation and chronic inflammation characteristic of HIV infection. Thus, the gut microbiota plays an integral role in maintaining the structure and function of the mucosal barrier, a critical factor for immune homeostasis. However, in the context of HIV infection, changes in the gut microbiota have been reported and have been linked to disease progression. Here, we review evidence for the role of the gut microbiota in intestinal homeostasis, its contribution to HIV pathogenesis, as well as its use in the development of therapeutic strategies.

C - reactive protein and interleukin - 6 levels among human immunodeficiency virus -infected patients with dysglycemia in Tanzania

BACKGROUND

Chronic inflammation has been associated with dysglycemia among people living with HIV (PLHIV). There is however, limited data regarding this phenomenon in sub-Sahara Africa (SSA). Therefore we assessed the levels of C-reactive protein (CRP) and Interleukin 6 (IL-6) on a cohort of PLHIV and its associations with dysglycemia in Tanzania.

METHODS

We conducted a cross-sectional study at the Infectious Disease Clinic (IDC) in Tanzania from March to May 2018. Purposive sampling was used to identify participants who had an undetectable viral load, were on 1st line anti-retroviral therapy (ART) and had an overnight fast. The WHO stepwise approach for non-communicable disease (NCD) surveillance was used to collect data. Fasting blood glucose and blood glucose after 75 g oral glucose load was measured, and Enzyme-linked immunosorbent assay (ELISA) was used to test for inflammatory markers (IL-6 and CRP). Associations were explored using the Chi square test and binary logistic regression was performed to estimate the odds ratios. A p-value less than 0.05 was considered statistically significant.

RESULTS

A total of 240 participants were enrolled. Forty two percent were overweight/obese (> 25 kg/m²), 89% had a high waist to height ratio. The median ART duration was 8(5-10) years. The prevalence of dysglycemia among our cohort of PLHIV was 32%. High CRP was associated with a 2.05 increased odds of having dysglycemia OR 2.05 (1.15-3.65) (p = 0.01). Taking stavudine was associated with a 1.99 odds of having dysglycemia OR 1.99 (1.04-3.82) (p = 0.03).We did not find a significant association between IL-6 and dysglycemia.

CONCLUSION

High CRP and taking stavudine were significantly associated with dysglycemia among PLHIV with undetectable viral load.

[HIV infection as a cause of accelerated aging and frailty]

The HIV-infected population is aging due to the success of combination antiretroviral therapy, which prolongs survival, as well as the growing number of newly diagnosed cases in adults 50 years old and over. HIV-infected individuals suffer from an accelerated aging due to the persistent and chronic activation of the immune system that leads to immune exhaustion and accelerated immunosenescence, even when on optimal immuno-virological control treatment. The clinical expression of the immunosenescence state is an increased prevalence of aging-related non-HIV associated comorbidities and a rising prevalence of frailty occurring earlier than in the general population. Thus, HIV-infected patients are biologically older than their chronological age, and they suffer from aging-related problems, such as frailty, which should be assessed.

Trends and predictors of non-communicable disease multimorbidity among adults living with HIV and receiving antiretroviral therapy in Brazil

INTRODUCTION

People living with HIV (PLHIV) on antiretroviral therapy (ART) experience high rates of non-communicable diseases (NCDs). These co-morbidities often accumulate and older adults may suffer from multimorbidity. Multimorbidity has been associated with loss of quality of life, polypharmacy, and increased risk of frailty and mortality. Little is known of the trends or predictors NCD multimorbidity in PLHIV in low- and middle-income countries.

METHODS

We examined NCD multimorbidity in adult PLHIV initiating ART between 2003 and 2014 using a multi-site, observational cohort in Brazil. NCDs included cardiovascular artery disease, hyperlipidemia (HLD), diabetes, chronic kidney disease, cirrhosis, osteoporosis, osteonecrosis, venous thromboembolism and non-AIDS-defining cancers. Multimorbidity was defined as the incident accumulation of two or more unique NCDs. We used Poisson regression to examine trends and Cox proportional hazard models to examine predictors of multimorbidity.

RESULTS

Of the 6206 adults, 332 (5%) developed multimorbidity during the study period. Parallel to the ageing of the cohort, the prevalence of multimorbidity rose from 3% to 11% during the study period. Older age, female sex (adjusted hazard ratio (aHR) = 1.30 (95% confidence interval (CI) 1.03 to 1.65)) and low CD4 nadir (<100 vs. ≥200 cells/mm3 aHR = 1.52 (95% CI: 1.15 to 2.01)) at cohort entry were significantly associated with increased risk of multimorbidity. Among patients with incident multimorbidity, the most common NCDs were HLD and diabetes; however, osteoporosis was also frequent in women (16 vs. 35% of men and women with multimorbidity respectively).

CONCLUSIONS

Among adult PLHIV in Brazil, NCD multimorbidity increased from 2003 to 2014. Females and adults with low CD4 nadir were at increased risk in adjusted analyses. Further studies examining prevention, screening and management of NCDs in PLHIV in low- and middle-income countries are needed.

Dysregulation of Neuronal Cholesterol Homeostasis upon Exposure to HIV-1 Tat and Cocaine Revealed by RNA-Sequencing

HIV-1 Tat protein is released from HIV-1-infected cells and can enter non-permissive cells including neurons. Tat disrupts neuronal homeostasis and may contribute to the neuropathogenesis in people living with HIV (PLWH). The use of cocaine by PLWH exacerbates neuronal dysfunction. Here, we examined the mechanisms by which Tat and cocaine facilitate alterations in neuronal homeostatic processes. Bioinformatic interrogation of the results from RNA deep sequencing of rat hippocampal neurons exposed to Tat alone indicated the dysregulation of several genes involved in lipid and cholesterol metabolism. Following exposure to Tat and cocaine, the activation of cholesterol biosynthesis genes led to increased levels of free cholesterol and cholesteryl esters in rat neurons. Results from lipid metabolism arrays validated upregulation of several processes implicated in the biogenesis of β-amyloid and Alzheimer’s disease (AD), including sterol o-acyltransferase 1/acetyl-coenzyme A acyltransferase 1 (SOAT1/ACAT1), sortilin-related receptor L1 (SORL1) and low-density lipoprotein receptor-related protein 12 (LRP12). Further studies in Tat-treated primary neuronal cultures and brain tissues from HIV-1 transgenic mice as well as SIV-infected macaques confirmed elevated levels of SOAT1/ACAT 1 proteins. Our results offer novel insights into the molecular events involved in HIV and cocaine-mediated neuronal dysfunction that may also contribute to neuropathogenic events associated with the development of AD.

Nicotinic Acetylcholine Receptors in HIV: Possible Roles During HAND and Inflammation

Infection with the human immunodeficiency virus (HIV) remains a threat to global health. Since its discovery, many efforts have been directed at understanding the mechanisms and consequences of infection. Although there have been substantial advances since the advent of antiretroviral therapy, there are still complications that significantly compromise the health of infected patients, particularly, chronic inflammation and HIV-associated neurocognitive disorders (HAND). In this review, a new perspective is addressed in the field of HIV, where the alpha7 nicotinic acetylcholine receptor (α7-nAChR) is the protagonist. We comprehensively discuss the available evidence implicating α7-nAChRs in the context of HIV and provide possible explanations about its role in HAND and inflammation in both the central nervous system and the periphery.

Early treatment of SIV+ macaques with an α4β7 mAb alters virus distribution and preserves CD4+ T cells in later stages of infection

Integrin α₄β₇ mediates the trafficking of leukocytes, including CD4⁺ T cells, to lymphoid tissues in the gut. Virus mediated damage to the gut is implicated in HIV and SIV mediated chronic immune activation and leads to irreversible damage to the immune system. We employed an immuno-PET/CT imaging technique to evaluate the impact of an anti-integrin α₄β₇ mAb alone or in combination with ART, on the distribution of both SIV infected cells and CD4⁺ cells in rhesus macaques infected with SIV. We determined that α₄β₇ mAb reduced viral antigen in an array of tissues of the lung, spleen, axillary, and inguinal lymph nodes. These sites are not directly linked to α₄β₇ mediated homing; however, the most pronounced reduction in viral load was observed in the colon. Despite this reduction, α₄β₇ mAb treatment did not prevent an apparent depletion of CD4⁺ T cells in gut in the acute phase of infection that is characteristic of HIV/SIV infection. However, α₄β₇ mAb appeared to facilitate the preservation or restoration of CD4⁺ T cells in gut tissues at later stages of infection. Since damage to the gut is believed to play a central role in HIV pathogenesis, these results support further evaluation of α₄β₇ antagonists in the study and treatment of HIV disease.

Redefining Aging in HIV Infection Using Phenotypes

Purpose of review

This article critically reviews the utility of “phenotypes” as behavioral descriptors in aging/HIV research that inform biological underpinnings and treatment development. We adopt a phenotypic redefinition of aging conceptualized within a broader context of HIV infection and of aging. Phenotypes are defined as dimensions of behavior, closely related to fundamental mechanisms, and, thus, may be more informative than chronological age. Primary emphasis in this review is given to comorbid aging and cognitive aging, though other phenotypes (i.e., disability, frailty, accelerated aging, successful aging) are also discussed in relation to comorbid aging and cognitive aging.

Recent findings

The main findings that emerged from this review are as follows: (1) the phenotypes, comorbid aging and cognitive aging, are distinct from each other, yet overlapping; (2) associative relationships are the rule in HIV for comorbid and cognitive aging phenotypes; and (3) HIV behavioral interventions for both comorbid aging and cognitive aging have been limited.

Summary

Three paths for research progress are identified for phenotype-defined aging/HIV research (i.e., clinical and behavioral specification, biological mechanisms, intervention targets), and some important research questions are suggested within each of these research paths.

Liver macrophage-associated inflammation correlates with SIV burden and is substantially reduced following cART

Liver disease is a leading contributor to morbidity and mortality during HIV infection, despite the use of combination antiretroviral therapy (cART). The precise mechanisms of liver disease during HIV infection are poorly understood partially due to the difficulty in obtaining human liver samples as well as the presence of confounding factors (e.g. hepatitis co-infection, alcohol use). Utilizing the simian immunodeficiency virus (SIV) macaque model, a controlled study was conducted to evaluate the factors associated with liver inflammation and the impact of cART. We observed an increase in hepatic macrophages during untreated SIV infection that was associated with a number of inflammatory and fibrosis mediators (TNFα, CCL3, TGFβ). Moreover, an upregulation in the macrophage chemoattractant factor CCL2 was detected in the livers of SIV-infected macaques that coincided with an increase in the number of activated CD16+ monocyte/macrophages and T cells expressing the cognate receptor CCR2. Expression of Mac387 on monocyte/macrophages further indicated that these cells recently migrated to the liver. The hepatic macrophage and T cell levels strongly correlated with liver SIV DNA levels, and were not associated with the levels of 16S bacterial DNA. Utilizing in situ hybridization, SIV-infected cells were found primarily within portal triads, and were identified as T cells. Microarray analysis identified a strong antiviral transcriptomic signature in the liver during SIV infection. In contrast, macaques treated with cART exhibited lower levels of liver macrophages and had a substantial, but not complete, reduction in their inflammatory profile. In addition, residual SIV DNA and bacteria 16S DNA were detected in the livers during cART, implicating the liver as a site on-going immune activation during antiretroviral therapy. These findings provide mechanistic insights regarding how SIV infection promotes liver inflammation through macrophage recruitment, with implications for in HIV-infected individuals.

The alpha7-nicotinic receptor contributes to gp120-induced neurotoxicity: implications in HIV-associated neurocognitive disorders

Currently, there are no specific therapies to treat HIV-1 associated neurocognitive disorders (HAND). The HIV-1 envelope, gp120, induces neuropathological changes similar to those in HAND patients; furthermore, it triggers an upregulation of the α7-nicotinic acetylcholine receptor (α7-nAChR), facilitating intracellular calcium overload and neuronal cell death. Using a gp120_IIIB-transgenic mouse (gp120-tgm) model, we demonstrate that α7-nAChRs are upregulated on striatal neurons. Activation of α7-nAChRs leads to an increase in both intracellular calcium and percentage of apoptotic cells, which can be abrogated by antagonizing the receptor, suggesting a role for α7-nAChRs in gp120-induced neurotoxicity. Moreover, we demonstrate for the first time that gp120-tgm have learning deficiencies on a striatum-dependent behavioral task. They also show locomotor deficiencies, which improved with α7-nAChR antagonists, further supporting a role for this receptor in gp120-induced neurotoxicity. Together, these results uncover a new mechanism through which gp120-induced modulation of α7-nAChRs in the striatum can contribute to HAND development.

Immune activation despite preserved CD4 T cells in perinatally HIV-infected children and adolescents

BACKGROUND

HIV disease progresses more rapidly in children than adults with mortality rates exceeding 50% by 2 years of age without antiretroviral therapy (ART) in sub-Saharan Africa. Recent World Health Organization (WHO) guidelines recommend universal treatment for all living persons with HIV, yet there is limited supporting evidence in pediatric populations. The objective of this study was to determine whether CD4 cell counts reflect immunological markers associated with disease progression in ART naïve perinatally-infected HIV+ children and adolescents and their response to ART.

METHODS

PBMC and plasma samples were collected from 71 HIV negative and 132 HIV+ children (65 ART naïve and 67 on ART) between ages 1-19 years from Mombasa, Kenya. Untreated HIV+ subjects were sub-categorized by high or low CD4 T cell counts. Immune activation markers CD38, HLA-DR and Ki67 were analyzed by flow cytometry. Plasma soluble CD14 (sCD14) was quantified by ELISA.

RESULTS

HIV-infected children and adolescents with preserved CD4 cell counts had depleted CD4 percentages and CD4:CD8 ratios, and high immune activation levels. ART initiation rapidly and persistently reversed T cell activation, but failed to normalize CD4:CD8 ratios and plasma sCD14 levels.

CONCLUSIONS

Diminished CD4 percentages and CD4:CD8 ratios along with profound immune activation occur independent of CD4 cell count thresholds in ART naïve HIV+ children and adolescents. Immediate ART initiation, as recommended in the most recent WHO guidelines may protect them from pathologic sequelae associated with persistent inflammation.

Reactivation of HIV-1 from Latency by an Ingenol Derivative from Euphorbia Kansui

Cells harboring latent HIV-1 pose a major obstacle to eradication of the virus. The ‘shock and kill’ strategy has been broadly explored to purge the latent reservoir; however, none of the current latency-reversing agents (LRAs) can safely and effectively activate the latent virus in patients. In this study, we report an ingenol derivative called EK-16A, isolated from the traditional Chinese medicinal herb Euphorbia kansui, which displays great potential in reactivating latent HIV-1. A comparison of the doses used to measure the potency indicated EK-16A to be 200-fold more potent than prostratin in reactivating HIV-1 from latently infected cell lines. EK-16A also outperformed prostratin in ex vivo studies on cells from HIV-1-infected individuals, while maintaining minimal cytotoxicity effects on cell viability and T cell activation. Furthermore, EK-16A exhibited synergy with other LRAs in reactivating latent HIV-1. Mechanistic studies indicated EK-16A to be a PKCγ activator, which promoted both HIV-1 transcription initiation by NF-κB and elongation by P-TEFb signal pathways. Further investigations aimed to add this compound to the therapeutic arsenal for HIV-1 eradication are in the pipeline.

HIV-1 Latency and Eradication: Past, Present and Future

BACKGROUND

It is well established that antiretroviral therapy (ART), while highly effective in controlling HIV replication, cannot eliminate virus from the body. Therefore, the majority of HIV-1-infected individuals remain at risk for developing AIDS due to persistence of infected reservoir cells serving as a source of virus re-emergence. Several reservoirs containing replication competent HIV-1 have been identified, most notably CD4+ T cells. Cells of the myeloid lineage, which are the first line of defense against pathogens and participate in HIV dissemination into sanctuary organs, also serve as cellular reservoirs of HIV-1. In latently infected resting CD4+ T cells, the integrated copies of proviral DNA remain in a dormant state, yet possess the ability to produce replication competent virus after cellular activation. Studies have demonstrated that modification of chromatin structure plays a role in establishing persistence, in part suggesting that latency is, controlled epigenetically.

CONCLUSION

Current efforts to eradicate HIV-1 from this cell population focus primarily on a &amp;quot;shock and kill&amp;quot; approach through cellular reactivation to trigger elimination of virus producing cells by cytolysis or host immune responses. However, studies revealed several limitations to this approach that require more investigation to assess its clinical application. Recent advances in gene editing technology prompted use of this approach for inactivating integrated proviral DNA in the genome of latently infected cells. This technology, which requires a detailed understanding of the viral genetics and robust delivery, may serve as a powerful strategy to eliminate the latent reservoir in the host leading to a sterile cure of AIDS.

Smoking and projected cardiovascular risk in an HIV-positive Asian regional cohort

OBJECTIVES

The aim of the study was to assess the prevalence and characteristics associated with current smoking in an Asian HIV-positive cohort, to calculate the predictive risks of cardiovascular disease (CVD), coronary heart disease (CHD) and myocardial infarction (MI), and to identify the impact that simulated interventions may have.

METHODS

Logistic regression analysis was used to distinguish associated current smoking characteristics. Five-year predictive risks of CVD, CHD and MI and the impact of simulated interventions were calculated utilizing the Data Collection on Adverse Effects of Anti-HIV Drugs Study (D:A:D) algorithm.

RESULTS

Smoking status data were collected from 4274 participants and 1496 of these had sufficient data for simulated intervention calculations. Current smoking prevalence in these two groups was similar (23.2% vs. 19.9%, respectively). Characteristics associated with current smoking included age > 50 years compared with 30-39 years [odds ratio (OR) 0.65; 95% confidence interval (CI) 0.51-0.83], HIV exposure through injecting drug use compared with heterosexual exposure (OR 3.03; 95% CI 2.25-4.07), and receiving antiretroviral therapy (ART) at study sites in Singapore, South Korea, Malaysia, Japan and Vietnam in comparison to Thailand (all OR > 2). Women were less likely to smoke than men (OR 0.11; 95% CI 0.08-0.14). In simulated interventions, smoking cessation demonstrated the greatest impact in reducing CVD and CHD risk and closely approximated the impact of switching from abacavir to an alternate antiretroviral in the reduction of 5-year MI risk.

CONCLUSIONS

Multiple interventions could reduce CVD, CHD and MI risk in Asian HIV-positive patients, with smoking cessation potentially being the most influential.

Immunometabolic and Lipidomic Markers Associated With the Frailty Index and Quality of Life in Aging HIV+ Men on Antiretroviral Therapy

Chronic immune activation persists despite antiretroviral therapy (ART) in HIV+ individuals and underpins an increased risk of age-related co-morbidities. We assessed the Frailty Index in older HIV+ Australian men on ART. Immunometabolic markers on monocytes and T cells were analyzed using flow cytometry, plasma innate immune activation markers by ELISA, and lipidomic profiling by mass spectrometry. The study population consisted of 80 HIV+ men with a median age of 59 (IQR, 56-65), and most had an undetectable viral load (92%). 24% were frail, and 76% were non-frail. Frailty was associated with elevated Glucose transporter-1 (Glut1) expression on the total monocytes (p=0.04), increased plasma levels of innate immune activation marker sCD163 (OR, 4.8; CI 1.4-15.9, p=0.01), phosphatidylethanolamine PE(36:3) (OR, 5.1; CI 1.7-15.5, p=0.004) and triacylglycerol TG(16:1_18:1_18:1) (OR, 3.4; CI 1.3-9.2, p=0.02), but decreased expression of GM3 ganglioside, GM3(d18:1/18:0) (OR, 0.1; CI 0.0-0.6, p=0.01) and monohexosylceramide HexCerd(d18:1/22:0) (OR, 0.1; CI 0.0-0.5, p=0.004). There is a strong inverse correlation between quality of life and the concentration of PE(36:3) (ρ=-0.33, p=0.004) and PE(36:4) (ρ=-0.37, p=0.001). These data suggest that frailty is associated with increased innate immune activation and abnormal lipidomic profile. These markers should be investigated in larger, longitudinal studies to determine their potential as biomarkers for frailty.

Persistence of Activated and Adaptive-Like NK Cells in HIV+ Individuals despite 2 Years of Suppressive Combination Antiretroviral Therapy

Innate immune dysfunction persists in HIV⁺ individuals despite effective combination antiretroviral therapy (cART). We recently demonstrated that an adaptive-like CD56^dim NK cell population lacking the signal transducing protein FcRγ is expanded in HIV⁺ individuals. Here, we analyzed a cohort of HIV⁺ men who have sex with men (MSM, n = 20) at baseline and following 6, 12, and 24 months of cART and compared them with uninfected MSM (n = 15) to investigate the impact of cART on NK cell dysfunction. Proportions of NK cells expressing markers of early (CD69⁺) and late (HLA-DR⁺/CD38⁺) activation were elevated in cART-naïve HIV⁺ MSM (p = 0.004 and 0.015, respectively), as were FcRγ⁻ NK cells (p = 0.003). Using latent growth curve modeling, we show that cART did not reduce levels of FcRγ⁻ NK cells (p = 0.115) or activated HLA-DR⁺/CD38⁺ NK cells (p = 0.129) but did reduce T cell and monocyte activation (p < 0.001 for all). Proportions of FcRγ⁻ NK cells were not associated with NK cell, T cell, or monocyte activation, suggesting different factors drive CD56^dim FcRγ⁻ NK cell expansion and immune activation in HIV⁺ individuals. While proportions of activated CD69⁺ NK cells declined significantly on cART (p = 0.003), the rate was significantly slower than the decline of T cell and monocyte activation, indicating a reduced potency of cART against NK cell activation. Our findings indicate that 2 years of suppressive cART have no impact on CD56^dim FcRγ⁻ NK cell expansion and that NK cell activation persists after normalization of other immune parameters. This may have implications for the development of malignancies and co-morbidities in HIV⁺ individuals on cART.

FOXP3+Helios+ Regulatory T Cells, Immune Activation, and Advancing Disease in HIV-Infected Children

Regulatory T cells (Tregs) are functionally suppressive CD4 T cells, critical for establishing peripheral tolerance and controlling inflammatory responses. Previous reports of Tregs during chronic HIV disease have conflicting results with higher or lower levels compared with controls. Identifying true Tregs with suppressive activity proves challenging during HIV infection, as traditional Treg markers, CD25 and FOXP3, may transiently upregulate expression as a result of immune activation (IA). Helios is an Ikaros family transcription factor that marks natural Tregs with suppressive activity and does not upregulate expression after activation. Coexpression of FOXP3 and Helios has been suggested as a highly specific marker of "bona fide" Tregs. We evaluated Treg subsets by FOXP3 coexpressed with either CD25 or Helios and their association with HIV disease progression in perinatally infected HIV-positive children. Identifying Tregs by FOXP3 coexpression with Helios rather than CD25 revealed markedly higher Treg frequencies, particularly in HIV+ children. Regardless of antiretroviral therapy, HIV-infected children had a selective expansion of memory FOXP3+Helios+ Tregs. The rise in memory Tregs correlated with declining HIV clinical status, indicated by falling CD4 percentages and CD4:CD8 ratios and increasing HIV plasma viremia and IA. In addition, untreated HIV+ children exhibited an imbalance between the levels of Tregs and activated T cells. Finally, memory Tregs expressed IA markers CD38 and Ki67 and exhaustion marker, PD-1, that tightly correlated with a similar phenotype in memory CD4 T cells. Overall, HIV-infected children had significant disruptions of memory Tregs that associated with advancing HIV disease.

Association of Hepatitis C Virus Infection With CD4/CD8 Ratio in HIV-Positive Women

Supplemental Digital Content is Available in the Text.

Background:

Recent studies reported that the CD4/CD8 T-cell ratio is inversely associated with biomarkers traditionally used to measure immune activation and systemic inflammation in highly active antiretroviral therapy–treated HIV-infected (HIV+) patients. The relation of hepatitis C virus (HCV) coinfection with the CD4/CD8 ratio in HIV+ patients is unknown.

Methods:

We examined 50,201 CD4/CD8 ratios measured over 20 years in 3 groups of HIV+ women enrolled in the Women's Interagency HIV Study: HCV antibody negative (n = 1734), cleared HCV (n = 231), and chronic HCV (n = 751) in multivariate models. IFNL4-ΔG genotype and HCV viral load were also considered.

Results:

Compared with HCV antibody negative status, chronic HCV infection was associated with lower CD4/CD8 ratios when HIV viral load was suppressed to the lower limit of quantification (β = −0.08; P = 0.002). Cleared HCV (β = −0.10; P = 0.0009), but not IFNL4-ΔG genotype or HCV viral load, was also associated with lower CD4/CD8 ratios when HIV viral load was suppressed to the lower limit of quantification.

Conclusions:

The association of HCV coinfection with CD4/CD8 ratio is consistent with previously observed associations of HCV coinfection with biomarkers traditionally used to measure immune activation and systemic inflammation in HIV+ patients. These data provide additional support for the use of CD4/CD8 ratio for routine monitoring of immune activation and inflammation in HIV+ patients, including those with HIV/HCV coinfection; however, the unexpected association between cleared HCV and lower CD4/CD8 ratio requires additional study.

Physical activity correlates in people living with HIV/AIDS: a systematic review of 45 studies

PURPOSE

Understanding barriers and facilitators of physical activity participation in persons living with HIV/AIDS is an essential first step in order to devise effective interventions. The present review provides a systematic quantitative review of the physical activity correlates in people with HIV/AIDS.

METHODS

Major electronic databases were searched till August 2016. Keywords included "physical activity" or "exercise" or "sports" and "AIDS" or "HIV".

RESULTS

Out of 55 correlates from 45 studies (N = 13,167; mean age range = 30.5-58.3 years; 63.2% male) five consistent (i.e., reported in four or more studies) correlates were identified. Lower levels of physical activity were consistently associated with older age (6/10 studies), a lower educational level (6/7), a lower number of CD4 cells/μl (7/11), exposure to antiviral therapy (4/6), and the presence of lipodystrophy (4/4). Other important barriers were the presence of bodily pain (2/2), depression (3/3), and opportunistic infections (3/4). Facilitators were a higher cardiorespiratory fitness level (3/3), a higher self-efficacy (2/2), more perceived benefits (2/2), and a better health motivation (3/3).

CONCLUSIONS

The current review has elucidated that participation in physical activity by people with HIV/AIDS is associated with a range of complex factors which should be considered in rehabilitation programs. Implications for Rehabilitation Health care professionals should consider HIV-related bodily pain and feelings of depression when assisting people living with HIV in inititiating and maintaining an active lifestyle. Interventions to improve self-efficacy and motivation, and to help people living with HIV in understanding the benefits of exercise, may encourage greater participation.

Systemic inflammation-based scores and mortality for all causes in HIV-infected patients: a MASTER cohort study

Background

Two biomarkers, the neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR), have been shown to be indicative of systemic inflammation and predictive of mortality in general population. We aimed to assess the association of NLR and PLR, with risk of death in HIV-infected subjects when also taking account of HIV-related factors.

Methods

We conducted a multicenter Italian cohort study from 2000 to 2012 including HIV-infected subjects naïve at antiretroviral treatment.

The associations of NLR and PLR with all-cause mortality were tested by univariate and multivariate analyses using both time independent and dependent Cox proportional hazard models. We also fitted models with a cubic-spline for PLR and NLR to evaluate the possible non-linear relationship between biomarkers values and risk of death.

Results

Eight-thousand and two hundred thirty patients (73.1% males) with a mean age of 38.4 years (SD 10.1) were enrolled. During a median follow-up of 3.9 years, 539 patients died. PLR < 100 and ≥ 200, as compared to PLR of 100–200, and NLR ≥ 2, as compared to < 2, were associated with risk of death at both univariate and multivariate analyses. Using multivariate models with restricted cubic-splines, we found a linear relationship of increasing risk of death with increasing values for NRL over 1.1, and an U-shape curve for PLR, with higher mortality risk for values higher or lower than 120.

Conclusions

Our data suggest that NLR and PLR can reflect the severity of the underlying systemic disturbance of the inflammatory process and coagulation leading to augmented mortality in HIV positive subjects.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2280-5) contains supplementary material, which is available to authorized users.

Novel AIDS therapies based on gene editing

HIV/AIDS remains a major public health issue. In 2014, it was estimated that 36.9 million people are living with HIV worldwide, including 2.6 million children. Since the advent of combination antiretroviral therapy (cART), in the 1990s, treatment has been so successful that in many parts of the world, HIV has become a chronic condition in which progression to AIDS has become increasingly rare. However, while people with HIV can expect to live a normal life span with cART, lifelong medication is required and cardiovascular, renal, liver, and neurologic diseases are still possible, which continues to prompt research for a cure for HIV. Infected reservoir cells, such as CD4+ T cells and myeloid cells, allow persistence of HIV as an integrated DNA provirus and serve as a potential source for the re-emergence of virus. Attempts to eradicate HIV from these cells have focused mainly on the so-called "shock and kill" approach, where cellular reactivation is induced so as to trigger the purging of virus-producing cells by cytolysis or immune attack. This approach has several limitations and its usefulness in clinical applications remains to be assessed. Recent advances in gene-editing technology have allowed the use of this approach for inactivating integrated proviral DNA in the genome of latently infected cells or knocking out HIV receptors. Here, we review this strategy and its potential to eliminate the latent HIV reservoir resulting in a sterile cure of AIDS.

Silymarin suppresses basal and stimulus-induced activation, exhaustion, differentiation, and inflammatory markers in primary human immune cells

Silymarin (SM), and its flavonolignan components, alter cellular metabolism and inhibit inflammatory status in human liver and T cell lines. In this study, we hypothesized that SM suppresses both acute and chronic immune activation (CIA), including in the context of HIV infection. SM treatment suppressed the expression of T cell activation and exhaustion markers on CD4+ and CD8+ T cells from chronically-infected, HIV-positive subjects. SM also showed a trend towards modifying CD4+ T cell memory subsets from HIV+ subjects. In the HIV-negative setting, SM treatment showed trends towards suppressing pro-inflammatory cytokines from non-activated and pathogen-associated molecular pattern (PAMP)-activated primary human monocytes, and non-activated and cytokine- and T cell receptor (TCR)-activated mucosal-associated invariant T (MAIT) cells. The data suggest that SM elicits broad anti-inflammatory and immunoregulatory activity in primary human immune cells. By using novel compounds to alter cellular inflammatory status, it may be possible to regulate inflammation in both non-disease and disease states.

Stimulation of PBMC and Monocyte-Derived Macrophages via Toll-Like Receptor Activates Innate Immune Pathways in HIV-Infected Patients on Virally Suppressive Combination Antiretroviral Therapy

In HIV-infected, combination antiretroviral therapy (cART)-treated patients, immune activation and microbial translocation persist and associate with inadequate CD4 recovery and morbidity/mortality. We analyzed whether alterations in the toll-like receptor (TLR) pathway could be responsible for the immune hyperactivation seen in these patients. PBMC/monocyte-derived macrophages (MDMs) of 28 HIV+ untreated and 35 cART-treated patients with HIV-RNA < 40 cp/mL [20 Full Responders (FRs): CD4 ≥ 350; 15 Immunological Non-Responders (INRs): CD4 < 350], as well as of 16 healthy controls were stimulated with a panel of TLR agonists. We measured: CD4/CD8/CD14/CD38/HLA-DR/Ki67/AnnexinV/CD69/TLR4/8 (Flow Cytometry); PBMC expression of 84 TLR pathway genes (qPCR); PBMC/MDM cytokine release (Multiplex); and plasma lipopolysaccharide (LPS)/sCD14 (LAL/ELISA). PBMC/MDM from cART patients responded weakly to LPS stimulation but released high amounts of pro-inflammatory cytokines. MDM from these patients were characterized by a reduced expression of HLA-DR+ MDM and failed to expand activated HLA-DR+ CD38+ T-lymphocytes. PBMC/MDM from cART patients responded more robustly to ssRNA stimulation; this resulted in a significant expansion of activated CD38 + CD8 and the release of amounts of pro-inflammatory cytokines comparable to those seen in untreated viremic patients. Despite greater constitutive TLR pathway gene expression, PBMC from INRs seemed to upregulate only type I IFN genes following TLR stimulation, whereas PBMC from full responders showed a broader response. Systemic exposure to microbial antigens drives immune activation during cART by triggering TLRs. Bacterial stimulation modifies MDM function/pro-inflammatory profile in cART patients without affecting T-lymphocytes; this suggests translocating bacteria as selective stimulus to chronic innate activation during cART. High constitutive TLR activation is seen in patients lacking CD4 recovery, suggesting an exhausted immune milieu, anergic to further antigen encounters.

Cardiorespiratory fitness levels and moderators in people with HIV: A systematic review and meta-analysis

Cardiorespiratory fitness (CRF) is a modifiable risk factor for cardiovascular disease and premature mortality. CRF levels and moderators among people living with HIV (PLWH) are unknown. The aim of the current meta-analysis was to (1) determine mean CRF in PLWH and compare levels with age- and gender-matched healthy controls (HCs), (2) explore moderators of CRF, (3) and (4) explore moderators of CRF outcomes following physical activity (PA) interventions. Major electronic databases were searched systematically for articles reporting CRF expressed as maximum or peak oxygen uptake (ml/min/kg) in PLWH. A random effects meta-analysis calculating the pooled mean CRF including subgroup- and meta-regression analyses was undertaken. Across 21 eligible studies, the CRF level was 26.4ml/kg/min (95% CI=24.6 to 28.1) (n=1010; mean age=41years). There were insufficient data to compare CRF levels with HCs. A higher body mass index (β=-0.99, 95% CI=-1.93 to -0.06, P=0.04), older age (β=-0.31, 95% CI=-0.58 to -0.04, P=0.02) and the presence of lipodystrophy (β=-4.63, 95% CI=-7.88 to -1.39, P=0.005) were significant moderators of lower CRF levels. Higher CD4+ counts (β=0.004, 95% CI=0.0007 to 0.007, P=0.016), supervised interventions (P<0.001) and interventions with a lower frequency of weekly sessions (2 or 3 versus 4 times) (P<0.001) predicted a better CRF-outcome following PA. CRF levels of PLWH are among the lowest in comparison to other vulnerable populations. More research on the most optimal physical activity intervention characteristics is needed.

Reverse geroscience: how does exposure to early diseases accelerate the age-related decline in health?

Aging is the major risk factor for both the development of chronic diseases and loss of functional capacity. Geroscience provides links among the biology of aging, the biology of disease, and the physiology of frailty, three fields where enormous progress has been made in the last few decades. While, previously, the focus was on the role of aging in susceptibility to disease and disability, the other side of this relationship, which is the contribution of disease to aging, has been less explored at the molecular/cellular level. Indeed, the role of childhood or early adulthood exposure to chronic disease and/or treatment on accelerating aging phenotypes is well known in epidemiology, but the biological basis is poorly understood. A recent summit co-organized by the National Institutes of Health GeroScience Interest Group and the New York Academy of Sciences explored these relationships, using three chronic diseases as examples: cancer, HIV/AIDS, and diabetes. The epidemiological literature clearly indicates that early exposure to any of these diseases and/or their treatments results in an acceleration of the appearance of aging phenotypes, including loss of functional capacity and accelerated appearance of clinical symptoms of aging-related diseases not obviously related to the earlier event. The discussions at the summit focused on the molecular and cellular relationships between each of these diseases and the recently defined molecular and cellular pillars of aging. Two major conclusions from the meeting include the desire to refine an operational definition of aging and to concomitantly develop biomarkers of aging, in order to move from chronological to physiological age. The discussion also opened a dialogue on the possibility of improving late-life outcomes in patients affected by chronic disease by including age-delaying modalities along with the standard care for the disease in question.

Dropout from physical activity interventions in people living with HIV: a systematic review and meta-analysis

Physical activity (PA) interventions have been shown to improve the health of people living with HIV (PLWH), yet treatment dropout poses an important challenge. We conducted a meta-analysis to investigate the prevalence and predictors of treatment dropout in PA interventions in PLWH. Electronic databases were searched for records up to September 2016. Randomized control trials of PA interventions in PLWH reporting dropout rates were included. Random effects meta-analysis and meta-regression analyses were employed. In 36 studies involving 49 PA intervention arms, 1128 PLWH were included (mean age = 41.6 years; 79.3% male; 39% White). The trim and fill adjusted treatment dropout rate was 29.3% (95% CI = 24.5-34.7%). There was a significant lower dropout rate in resistance training interventions compared with aerobic (p = 0.003) PA interventions, in studies utilizing supervised interventions throughout the study period (p < 0.001), and in studies using adequately qualified professionals (p < 0.001). Exerciser/participant variables that moderated higher dropout rates were a lower percentage of male participants (β = 1.15, standard error (SE) = 0.49, z = 2.0, p = 0.048), a lower body mass index(BMI) (β = 0.14, SE = 0.06, z = 2.16, p = 0.03), and a lower cardiorespiratory fitness (β = 0.10, SE = 0.04, z = 2.7, p = 0.006). The dropout from PA interventions is much higher in PLWH than in many other populations with chronic morbidities. Qualified professionals (i.e., exercise physiologists, physical educators, or physical therapists) should be incorporated as key care providers in the multidisciplinary care of HIV/AIDS and should prescribe supervised PA for PLWH in order to enhance adherence and reduce the burden of HIV/AIDS. Special attention should be given men, those with a higher BMI, and those with a lower cardiorespiratory fitness.

Lymphocyte-mediated Immune Regulation in Health and Disease: The Treg and γδ T Cell Co-conspiracy

The significance of lymphocytes functioning to mediate immunological tolerance has garnered increasing appreciation during the last several decades. CD4+ CD25+ α/ β T cells have arguably been the most extensively studied regulatory lymphocyte to date, perhaps owing to the dramatic phenotype observed mice and humans with mutated Foxp3. However, emerging studies suggest that the lineage of regulatory lymphocytes is quite robust. Most notably, while γδ T cells are more traditionally regarded as mediators of cytotoxic function, they are beginning to be regarded as potential negative regulators of immunity. While regulatory γ/δ T cells may possess a degree of transcriptional overlap with 'classical Tregs', there remains less clarity in regard to the mechanisms driving the suppressive potential of these cells. In this review, I will discuss the role of Tregs in establishing tolerance in the steady state as well as disease, and how their accumulation and function may be modulated by myeloid cells in the local microenvironment. I will also discuss the necessity to extend our understanding of the regulatory nature of γδ T cells, which may lead to the unearthing of novel paradigms of immunity, perhaps most notably with respect to cancer.

Prevalence of aortic valve dystrophy and insufficiency in a cohort of 255 HIV-positive patients followed-up in a cardiology department between 2012 and 2014

OBJECTIVES

To study valve appearance and the presence of valve disease in a cohort of people living with HIV (PLHIV).

DESIGN

A prospective study of PLHIV examined at the cardiology department of the Clermont Ferrand university hospital group (CHU) between January 1, 2012, and December 31, 2014. Were excluded those with a history of infection associated with a possible endocarditis.

METHODS

Demographic, medical characteristics and cardiovascular disease risk factors at time of cardiovascular examination and Doppler-echocardiography were recorded and analyzed.

RESULTS

In total, 903 PLHIV were examined in the infectious diseases department, 255 of whom were included. These consisted of 67 women (26.3%) and 188 men, of a mean age of 51.2±9.7years, in whom coronary artery disease was diagnosed in 18 patients (7.0%), two women and 16 men, representing a prevalence of 3.0% in females and 8.5% in males. The appearance of the aortic cusps was considered dystrophic in 14.1% of cases (36/255), dysplastic in two cases (0.8%), exhibiting a bicuspid deformity in one case. The prevalence of aortic valve abnormality was therefore 6.0% in the women (4/67) and 17.0% in the men (32/188). On facing off this data with the Kora Monica study findings, an increase in prevalence appears only to truly manifest after 50years of age. We registered 35 aortic insufficiency cases (13.7%), representing a higher incidence than that of the Framingham cohort, with age and masculine gender being the determining factors.

CONCLUSION

Valve disease, along with coronary artery disease, should be closely monitored in PLHIV.

Impact of age on care pathways of people living with HIV followed up in hospital

The aging population of people living with human immunodeficiency virus (HIV) (PLWH) is exposed to a widening spectrum of non-AIDS-defining diseases. Thus, our objective was to compare the health care offered to PLWH according to age. We conducted a multicenter cross-sectional study on PLWH who consulted at one of 59 French HIV reference centers from 15th to 19th October 2012. Using our survey questionnaires, PLWH self-reported the medical care they received, whether or not tied to HIV infection monitoring, during the previous year. A total of 650 PLWH participated in the survey (median age 48 years, Interquartile range (IQR) 40-54), of which 95 were aged 60 years or over (14.5%). Compared to younger PLWH, 60-and-over PLWH were more often under complementary health insurance cover and less socially deprived based on the French EPICES (Evaluation of Precarity and Inequalities in Health Examination Centers) score. The elderly PLWH presented more comorbidities and less coinfections with hepatitis viruses. During health care, therapeutic education was less often offered to older PLWH (14% vs. 26%, p = .01), but this difference was mainly explained by sociodemographic factors and clinical status. Over the previous 6 months, 74% of PLWH who were followed up in hospital had also consulted another doctor, with a mean of 3.75 consultations (±4.18) without difference between age groups. After adjustment for sociodemographic factors and comorbidities, PLWH over 60 years were more likely to have consulted medical specialists as outpatients in the last 6 months (odds ratio [OR] = 2.63 [1.11-6.20]). Whatever their age, 13% of PLWH had been refused care on disclosure of their HIV status, and 27% of PLWH still did not disclose their HIV status to some caregivers. Coordinated health care throughout patients' lives is crucial, as health-care pathways evolve toward outpatient care as the patients get older.

The World report on ageing and health: a policy framework for healthy ageing

Although populations around the world are rapidly ageing, evidence that increasing longevity is being accompanied by an extended period of good health is scarce. A coherent and focused public health response that spans multiple sectors and stakeholders is urgently needed. To guide this global response, WHO has released the first World report on ageing and health, reviewing current knowledge and gaps and providing a public health framework for action. The report is built around a redefinition of healthy ageing that centres on the notion of functional ability: the combination of the intrinsic capacity of the individual, relevant environmental characteristics, and the interactions between the individual and these characteristics. This Health Policy highlights key findings and recommendations from the report.

Immunity in young adult survivors of childhood leukemia is similar to the elderly rather than age-matched controls: Role of cytomegalovirus

Many treatment complications that occur late in childhood cancer survivors resemble age-related comorbidities observed in the elderly. An immune phenotype characterized by increased immune activation, systemic inflammation, and accumulation of late-differentiated memory CD57(+) CD28(-) T cells has been associated with comorbidities in the elderly. Here, we explored if this phenotype was present in young adult leukemia survivors following an average of 19 years from chemotherapy and/or radiotherapy completion, and compared this with that in age-matched controls. We found that markers of systemic inflammation-IL-6 and human C-reactive protein and immune activation-CD38 and HLA-DR on T cells, soluble CD (sCD)163 from monocytes and macrophages-were increased in survivors compared to controls. T-cell responses specific to cytomegalovirus (CMV) were also increased in survivors compared to controls while CMV IgG levels in survivors were comparable to levels measured in the elderly (>50years) and correlated with IL-6, human C-reactive protein, sCD163, and CD57(+) CD28(-) memory T cells. Immune activation and inflammation markers correlated poorly with prior chemotherapy and radiotherapy exposure. These data suggest that CMV infection/reactivation is strongly correlated with the immunological phenotype seen in young childhood leukemia survivors and these changes may be associated with the early onset of age-related comorbidities in this group.

The α7-nicotinic receptor is upregulated in immune cells from HIV-seropositive women: consequences to the cholinergic anti-inflammatory response

Antiretroviral therapy partially restores the immune system and markedly increases life expectancy of HIV-infected patients. However, antiretroviral therapy does not restore full health. These patients suffer from poorly understood chronic inflammation that causes a number of AIDS and non-AIDS complications. Here we show that chronic inflammation in HIV+ patients may be due to the disruption of the cholinergic anti-inflammatory pathway by HIV envelope protein gp120_IIIB. Our results demonstrate that HIV gp120_IIIB induces α7 nicotinic acetylcholine receptor (α7) upregulation and a paradoxical proinflammatory phenotype in macrophages, as activation of the upregulated α7 is no longer capable of inhibiting the release of proinflammatory cytokines. Our results demonstrate that disruption of the cholinergic-mediated anti-inflammatory response can result from an HIV protein. Collectively, these findings suggest that HIV tampering with a natural strategy to control inflammation could contribute to a crucial, unresolved problem of HIV infection: chronic inflammation.

Frailty, Inflammation, and Mortality Among Persons Aging With HIV Infection and Injection Drug Use

BACKGROUND

Serum markers of inflammation increase with age and have been strongly associated with adverse clinical outcomes among both HIV-infected and uninfected adults. Yet, limited data exist on the predictive and clinical utility of aggregate measures of inflammation. This study sought to evaluate the relationship of a recently validated aggregate inflammatory index with frailty and mortality among aging HIV-infected and uninfected injection drug users.

METHODS

Frailty was assessed among HIV-infected and uninfected participants in the AIDS Linked to the IntraVenous Experience (ALIVE) cohort study using the five Fried phenotypic criteria: weight loss, exhaustion, low physical activity, decreased grip strength, and slow gait. The aggregate inflammatory index was constructed from serum measures of interleukin-6 and soluble tumor necrosis factor-α receptor-1. Multinomial logistic regression was used to assess the relationship of frailty with inflammation. Cox proportional hazards models were used to estimate risk for all-cause mortality.

RESULTS

Among 1,326 subjects, the median age was 48 years and 29% were HIV-infected. Adjusting for sociodemographics, comorbidity, and HIV status, frailty was significantly associated with each standard deviation increase in log interleukin-6 (odds ratio 1.33; 95% CI, 1.09-1.61), log tumor necrosis factor-α receptor-1 (odds ratio 1.25; 95% CI, 1.04-1.51) and inflammatory index score (odds ratio 1.39; 95% CI, 1.14-1.68). Adjusting for sociodemographics, comorbidity, HIV status, and frailty, the inflammatory index score was independently associated with increased mortality (HR 1.65; 95% CI, 1.44-1.89).

CONCLUSION

A recently validated, simple, biologically informed inflammatory index is independently associated with frailty and mortality risk among aging HIV-infected and uninfected injection drug users.

Monocytes from HIV-infected individuals show impaired cholesterol efflux and increased foam cell formation after transendothelial migration

DESIGN

HIV-infected (HIV+) individuals have an increased risk of atherosclerosis and cardiovascular disease which is independent of antiretroviral therapy and traditional risk factors. Monocytes play a central role in the development of atherosclerosis, and HIV-related chronic inflammation and monocyte activation may contribute to increased atherosclerosis, but the mechanisms are unknown.

METHODS

Using an in-vitro model of atherosclerotic plaque formation, we measured the transendothelial migration of purified monocytes from age-matched HIV+ and uninfected donors and examined their differentiation into foam cells. Cholesterol efflux and the expression of cholesterol metabolism genes were also assessed.

RESULTS

Monocytes from HIV+ individuals showed increased foam cell formation compared with controls (18.9 vs. 0%, respectively, P = 0.004) and serum from virologically suppressed HIV+ individuals potentiated foam cell formation by monocytes from both uninfected and HIV+ donors. Plasma tumour necrosis factor (TNF) levels were increased in HIV+ vs. control donors (5.9 vs. 3.5 pg/ml, P = 0.02) and foam cell formation was inhibited by blocking antibodies to TNF receptors, suggesting a direct effect on monocyte differentiation to foam cells. Monocytes from virologically suppressed HIV+ donors showed impaired cholesterol efflux and decreased expression of key genes regulating cholesterol metabolism, including the cholesterol transporter ABCA1 (P = 0.02).

CONCLUSION

Monocytes from HIV+ individuals show impaired cholesterol efflux and are primed for foam cell formation following transendothelial migration. Factors present in HIV+ serum, including elevated TNF levels, further enhance foam cell formation. The proatherogenic phenotype of monocytes persists in virologically suppressed HIV+ individuals and may contribute mechanistically to increased atherosclerosis in this population.

Hormonal Contraception and Risk of Psychiatric and Other Noncommunicable Diseases in HIV-Infected Women

BACKGROUND

Hormonal contraception use is common among human immunodeficiency virus (HIV)-infected women. Risk of psychiatric and other noninfectious complications of hormonal contraception use has not been described in this population.

METHODS

We performed a retrospective cohort study of HIV-infected women receiving care in Tennessee from 1998 to 2008 to examine the risks of incident psychiatric and other noncommunicable diseases (NCDs), including cardiovascular, hepatic, renal, and malignant diseases, and hormonal contraception use, including depot medroxyprogesterone acetate (DMPA) and combined estrogen- and progestin-containing hormonal contraceptives. We used marginal structural models with inverse probability weights to account for time-varying confounders associated with hormonal contraception use.

RESULTS

Of the 392 women included, 94 (24%) used hormonal contraception during the study period. Baseline psychiatric disease was similar between women who received and did not receive hormonal contraception. There were 69 incident psychiatric diagnoses and 72 NCDs. Only time-varying DMPA use was associated with increased risk of psychiatric disease (adjusted odds ratio [aOR] 3.70; 95% confidence interval [95% CI] 1.32-10.4) and mood disorders, specifically (aOR 4.70 [1.87-11.8]). Time-varying and cumulative combined hormonal contraception use were not statistically associated with other NCDs (aOR 1.64, 95% CI 0.64-4.12 and aOR 1.16, 95% CI 0.86-1.56, respectively). However, risk of incident NCDs was increased with cumulative DMPA exposure (per year exposure aOR 1.45, 95% CI 1.01-2.08).

CONCLUSIONS

Among HIV-infected women, DMPA was associated with risk of incident psychiatric diseases, particularly mood disorders, during periods of use. Cumulative DMPA exposure was also associated with risk of other NCDs. However, combined estrogen and progestin-containing hormonal contraception use was not statistically associated with risk of any NCDs.

Viremic and Virologically Suppressed HIV Infection Increases Age-Related Changes to Monocyte Activation Equivalent to 12 and 4 Years of Aging, Respectively

BACKGROUND

Chronic inflammation and immune activation occur in both HIV infection and normal aging and are associated with inflammatory disease. However, the degree to which HIV influences age-related innate immune changes, and the biomarkers which best reflect them, remains unclear.

METHODS AND RESULTS

We measured established innate immune aging biomarkers in 309 individuals including 88 virologically suppressed (VS) and 52 viremic (viral load ≤ and >50 copies per milliliter, respectively) HIV-positive individuals. Levels of soluble (ie, CXCL10, soluble CD163, neopterin) and cellular (ie, proportions of inflammatory CD16 monocytes) biomarkers of monocyte activation were increased in HIV-positive individuals and were only partially ameliorated by viral suppression. Viremic and VS HIV-positive individuals show levels of age-related monocyte activation biomarkers that are similar to uninfected controls aged 12 and 4 years older, respectively. Viremic HIV infection was associated with an accelerated rate of change of some monocyte activation markers (eg, neopterin) with age, whereas in VS individuals, subsequent age-related changes occurred at a similar rate as in controls, albeit at a higher absolute level. We further identified CXCL10 as a robust soluble biomarker of monocyte activation, highlighting the potential utility of this chemokine as a prognostic marker.

IMPLICATIONS

These findings may partially explain the increased prevalence of inflammatory age-related diseases in HIV-positive individuals and potentially indicate the pathological mechanisms underlying these diseases, which persist despite viral suppression.

Vitamin D Deficiency in HIV Infection: Not Only a Bone Disorder

Hypovitaminosis D is a worldwide disorder, with a high prevalence in the general population of both Western and developing countries. In HIV patients, several studies have linked vitamin D status with bone disease, neurocognitive impairment, depression, cardiovascular disease, high blood pressure, metabolic syndrome, type 2 diabetes mellitus, infections, autoimmune diseases like type 1 diabetes mellitus, and cancer. In this review, we focus on the most recent epidemiological and experimental data dealing with the relationship between vitamin D deficiency and HIV infection. We analysed the extent of the problem, pathogenic mechanisms, clinical implications, and potential benefits of vitamin D supplementation in HIV-infected subjects.

Plasma levels of cytokines and chemokines and the risk of mortality in HIV-infected individuals: a case-control analysis nested in a large clinical trial

BACKGROUND

All-cause mortality and serious non-AIDS events (SNAEs) in individuals with HIV-1 infection receiving antiretroviral therapy are associated with increased production of interleukin-6 which appears to be driven by monocyte/macrophage activation. Plasma levels of other cytokines or chemokines associated with immune activation might also be biomarkers of an increased risk of mortality and/or SNAEs.

METHODS

Baseline plasma samples from 142 participants enrolled into the Strategies for Management of Antiretroviral Therapy study, who subsequently died, and 284 matched controls, were assayed for levels of 15 cytokines and chemokines. Cytokine and chemokine levels were analysed individually and when grouped according to function (innate/proinflammatory response, cell trafficking and cell activation/proliferation) for their association with the risk of subsequent death.

RESULTS

Higher plasma levels of proinflammatory cytokines (interleukin-6 and tumour necrosis factor-α) were associated with an increased risk of all-cause mortality but in analyses adjusted for potential confounders, only the association with interleukin-6 persisted. Increased plasma levels of the chemokine CXCL8 were also associated with all-cause mortality independently of hepatitis C virus status but not when analyses were adjusted for all confounders. In contrast, higher plasma levels of cytokines mediating cell activation/proliferation were not associated with a higher mortality risk and exhibited a weak protective effect when analysed as a group.

CONCLUSION

Whereas plasma levels of interleukin-6 are the most informative biomarker of cytokine dysregulation associated with all-cause mortality in individuals with HIV-1 infection, assessment of plasma levels of CXCL8 might provide information about causes of mortality and possibly SNAEs.