Immunologic Biomarkers, Morbidity, and Mortality in Treated HIV Infection

Stability of plasma indices of inflammation/coagulation and homeostasis after fatty and non-fatty meals in treated people with HIV

OBJECTIVES

The relationship between lipid levels in plasma and inflammatory indices is complex and fatty meals alter plasma inflammatory markers in people with diabetes. There is interest in monitoring the effects of interventions on plasma inflammatory and coagulation elements in people with HIV, as they have been linked to risk for morbid outcomes and HIV persistence. Understanding the effects of feeding and time of specimen acquisition is important for the correct scheduling of clinical sampling.

METHODS

We examined the effects of feeding on plasma inflammatory, coagulation and homeostatic indices among 24 non-diabetic people with HIV, with controlled viraemia and on antiretroviral therapy after fasting and then 1, 3 and 6 hours after ingesting a fatty meal, and also approximately 1 week later after fasting and after an isocaloric non-fatty meal. Plasma levels of IL-6, IL-7, IP-10, sCD14, sCD163, sTNFrII and D-dimer were monitored by immunoassay.

RESULTS

Fasting levels of all markers obtained approximately 1 week apart were significantly correlated (P<0.001). Mild alterations in plasma concentrations of inflammatory markers were observed after feeding but geometric means varied more than 10% from baseline for only IL-6 and IL-7. Meal type was differentially associated with changes in plasma levels for IL-7 only. Antiretroviral treatment regimen, body mass index and changes in plasma triglyceride levels were not linked to post-feeding changes in these biomarkers.

CONCLUSIONS

These plasma inflammatory, coagulation and homeostatic indices are relatively stable at fasting and are only minimally affected by feeding or time of day. These findings will aid in the monitoring of inflammatory and homeostatic indices that may contribute to control of HIV expression and its persistence.

Crosstalk in competing endogenous RNA networks reveals new circular RNAs involved in the pathogenesis of early HIV infection

Background

The events in early HIV infection (EHI) are important determinants of disease severity and progression rate to AIDS, but the mechanisms of pathogenesis in EHI have not been fully understood. Circular RNAs (circRNAs) have been verified as “microRNA sponges” that regulate gene expression through competing endogenous RNA (ceRNA) networks, but circRNA expression profiles and their contribution to EHI pathogenesis are still unclear.

Methods

Two different libraries were constructed with RNA from human peripheral blood mononuclear cells from 3 HARRT-naive EHI patients and 3 healthy controls (HCs). The complete transcriptomes were sequenced with RNA sequencing (RNA-Seq) and miRNA sequencing (miRNA-Seq). The differentially expressed (DE) RNAs were validated with RT-qPCR. The circRNA profile and circRNA-associated-ceRNA network in EHI were analyzed with the integrated data of RNA-Seq and miRNA-Seq. Gene ontology (GO) analysis was used to annotate the circRNAs involved in the circRNA-associated-ceRNA networks.

Results

A total of 1365 circRNAs, 30 miRNAs, and 2049 mRNAs were differentially expressed between HARRT-naive EHI patients and HCs. A ceRNA network was constructed with 516 DE circRNAs and 903 DE mRNAs that shared miR response elements with 21 DE miRNAs. GO analysis demonstrated the multiple roles of the circRNAs enriched in EHI with circRNA-associated-ceRNA networks, such as immune response, inflammatory response and defense responses to virus, 67 circRNAs were revealed to be potentially involved in HIV-1 replication through regulating the expression of CCNK, CDKN1A and IL-15.

Conclusions

This study, for the first time, revealed a large circRNA profile and complex pathogenesis roles of circRNAs in EHI. A group of enriched circRNAs and associated circRNA-associated-ceRNA networks might contribute to HIV replication regulation and provide novel potential targets for both the pathogenesis of EHI and antiviral therapy.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1706-1) contains supplementary material, which is available to authorized users.

Serum concentration of anti-Cytomegalovirus IgG and ischaemic stroke in patients with advanced HIV infection in Malawi

BACKGROUND

Studies in high-income settings have shown association between Cytomegalovirus (CMV) infection and adverse cardiovascular outcome, especially in HIV infection. We aimed to study the association between serum concentration of anti-CMV IgG and ischaemic stroke in HIV-infected Malawians.

METHODS

Our sample was derived from a case-control stroke study in Malawi. Serum concentration of anti-CMV IgG was measured using enzyme-linked immunosorbent assay. Multivariable logistic regression was used to study the association between high concentrations of anti-CMV IgG (above the third tertile) and ischaemic stroke while adjusting for cardiovascular risk factors.

RESULTS

Overall, 139 HIV-positive adults (48.2% women; 48 ischaemic stroke cases and 91 controls; median age: 45 years) were included. The median CD4+ count was 136 and 401 cell/mm3 (IQR: [75-278] and [230-533]) in cases and controls, respectively. High concentration of anti-CMV IgG was associated with ischaemic stroke in the univariable model (OR = 2.56 [1.23-5.34]) but not after adjusting for duration of antiretroviral therapy (ART), CD4+ count, and other cardiovascular risk factors (OR = 0.94 [0.29-3.08]). Low CD4+ count was an independent predictor of stroke. There was a negative correlation between serum concentration of anti-CMV IgG and CD4+ count (rho = -0.30, p < 0.001).

CONCLUSIONS

High concentration of anti-CMV IgG is not independently associated with ischaemic stroke in HIV-infected Malawians. Larger cohort studies are needed to further investigate the role of humoral response to CMV in the pathophysiology of HIV-associated stroke.

Comparison of bead array and glass nanoreactor multi-analyte platforms for the evaluation of CNS and peripheral inflammatory markers during HIV infection

While human immunodeficiency virus (HIV) infection has become a treatable disease with the development of combination antiretroviral therapy (cART), chronic inflammation that affects the central nervous system and other organs is still common. Reliable methods are needed to study HIV-associated inflammatory biomarkers. In this study involving both plasma and cerebrospinal fluid (CSF), we compared multiplex bead array (MBA) to a relatively new technology based on microfluidics and glass nanoreactor (GNR) technology for the measurement of three commonly studied markers from HIV-infected individuals. We found that results correlated between the two platforms for MCP-1 in both fluids as well as for plasma TNFα (all p < .005). However, results between the two platforms did not correlate for CSF TNFα or fractalkine from plasma or CSF. A statistically significant decrease in CSF TNFα over time (p < .0001) was only detectable with the MBA platform, and TNFα on the MBA was the only CSF biomarker to correlate with CSF HIV RNA (rho = 0.71, p < .0001). Meanwhile, the GNR platform was superior in terms of intra-assay fractalkine (FKN) variability and the detection of a significant FKN decrease over time. Additionally, the only significant correlation between blood biomarkers and plasma HIV RNA was with FKN on the GNR platform (rho = 0.38, p = .015). Given the variability in results between platforms, more research is needed on methods to quantitate HIV-associated inflammation.

HIV

The benefits of combination antiretroviral therapy (cART) for HIV replication and transmission control have led to its universal recommendation. Many people living with HIV are, however, still undiagnosed or diagnosed late, especially in sub-Saharan Africa, where the HIV disease burden is highest. Further expansion in HIV treatment options, incorporating women-centred approaches, is essential to make individualised care a reality. With a longer life expectancy than before, people living with HIV are at an increased risk of developing non-AIDS comorbidities, such as cardiovascular diseases and cancers. Antiretroviral strategies are evolving towards a decrease in drug burden, and some two-drug combinations have proven efficacy for maintenance therapy. Investigational immune checkpoint inhibitors and broadly neutralising antibodies with effector functions have energised the HIV cure research field as the search for an effective vaccine continues. In this Seminar, we review advances and challenges relating to the goal of an AIDS-free world.

Adenosine signaling and adenosine deaminase regulation of immune responses: impact on the immunopathogenesis of HIV infection

Infection by human immunodeficiency virus (HIV) causes the acquired immune deficiency syndrome (AIDS), which has devastating effects on the host immune system. HIV entry into host cells and subsequent viral replication induce a proinflammatory response, hyperactivating immune cells and leading them to death, disfunction, and exhaustion. Adenosine is an immunomodulatory molecule that suppresses immune cell function to protect tissue integrity. The anti-inflammatory properties of adenosine modulate the chronic inflammation and immune activation caused by HIV. Lack of adenosine contributes to pathogenic events in HIV infection. However, immunosuppression by adenosine has its shortcomings, such as impairing the immune response, hindering the elimination of the virus and control of viral replication. By attempting to control inflammation, adenosine feeds a pathogenic cycle affecting immune cells. Deamination of adenosine by ADA (adenosine deaminase) counteracts the negative effects of adenosine in immune cells, boosting the immune response. This review comprises the connection between adenosinergic system and HIV immunopathogenesis, exploring defects in immune cell function and the role of ADA in protecting these cells against damage.

APOBEC3G/3A Expression in Human Immunodeficiency Virus Type 1-Infected Individuals Following Initiation of Antiretroviral Therapy Containing Cenicriviroc or Efavirenz

Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3 (APOBEC3) family members are cytidine deaminases that play crucial roles in innate responses to retrovirus infection. The mechanisms by which some of these enzymes restrict human immunodeficiency virus type 1 (HIV-1) replication have been extensively investigated in vitro. However, little is known regarding how APOBEC3 proteins affect the pathogenesis of HIV-1 infection in vivo and how antiretroviral therapy influences their expression. In this work, a longitudinal analysis was performed to evaluate APOBEC3G/3A expression in peripheral blood mononuclear cells of antiretroviral-naive HIV-1-infected individuals treated with cenicriviroc (CVC) or efavirenz (EFV) at baseline and 4, 12, 24, and 48 weeks post-treatment follow-up. While APOBEC3G expression was unaffected by therapy, APOBEC3A levels increased in CVC but not EFV arm at week 48 of treatment. APOBEC3G expression correlated directly with CD4⁺ cell count and CD4⁺/CD8⁺ cell ratio, whereas APOBEC3A levels inversely correlated with plasma soluble CD14. These findings suggest that higher APOBEC3G/3A levels may be associated with protective effects against HIV-1 disease progression and chronic inflammation and warrant further studies.

Multimorbidity, age-related comorbidities and mortality: association of activation, senescence and inflammation markers in HIV adults

BACKGROUND

The widespread introduction of combination antiretroviral therapy (cART) has increased survival of HIV-infected patients. However, the prevalence of age-related comorbidities remains higher than that of the general population, suggesting that individuals with HIV suffer from accelerated aging. Immune activation, senescence and inflammation could play an important role in this process.

METHODS

The CIADIS (Chronic Immune Activation anD Senescence) sub-study analyzed biomarkers of activation, differentiation and senescence of T cells in a cellular-CIADIS-weighted score, whereas biomarkers of inflammation were analyzed in a soluble CIADIS-weighted score using principal component analysis. Adjusted logistic regression and Cox proportional hazard models were used to determine the association between CIADIS-weighted scores and the presence of multimorbidity, time to occurrence of the first new age-related comorbidity and time to death, over a 3-year follow-up period.

RESULTS

Of 828 patients with an undetectable viral load, a higher cellular-CIADIS-weighted score and higher TNFRI levels were independently associated with the presence of multimorbidity (OR 1.3; 95% CI 1.0-1.6; P = 0.02), but the soluble CIADIS-weighted score was not (OR = 1.1; 95% CI 0.9-1.3; P = 0.33). A higher cellular CIADIS-weighted score (hazard ratio 2.2; P < 0.01), higher levels of CD8 activation and a lower CD4/CD8 ratio were associated with a higher risk of age-related comorbidities. Only TNFRI was associated with mortality in a 3-year period.

CONCLUSION

The cellular CIADIS-weighted score was independently associated with both multimorbidity at inclusion and the risk of new age-related comorbidity during a 3- year follow-up. TNFRI was associated a higher risk for mortality.

Suppressive antiretroviral therapy associates with effective treatment of high-grade cervical intraepithelial neoplasia

OBJECTIVES

To assess if women living with HIV (WLWH) have poorer outcome after treatment of cervical intraepithelial neoplasia grade 2, grade 3, adenocarcinoma in situ or cervical cancer (CIN2+) than HIV-negative women (HNW) and to identify predictors of CIN2+ treatment failure and recurrence in WLWH.

DESIGN

Population-based cohort study with follow-up between 1983 and 2015.

METHODS

The Swedish National HIV Registry, the Swedish Population Registry and the Swedish National Cervical Screening Registry were linked to identify all women in Stockholm and Gothenburg counties (Sweden) living with HIV and diagnosed with CIN2+ (n = 179) sometime between 1983 and 2014. For each WLWH, two HNW resident in the same counties and matched for country of birth, diagnosed with CIN2+, were chosen as controls. Treatment failure was defined as the presence of CIN2+ at initial follow-up. Recurrence was defined as the presence of CIN1+ subsequent to an initial normal follow-up.

RESULTS

WLWH were three times more likely to have treatment failure (odds ratio (OR) 3.7 [95% confidence interval (CI) 2.0-6.8]) and five times more likely to recur (hazard ratio 5.0 [95% CI 2.1-11.6]) than HNW. Suppressive antiretroviral therapy (ART) at time of treatment of CIN2+ was associated with reduced OR of treatment failure (OR 0.3 [95% CI 0.1-0.8]). Immunosuppression (CD4 cell count <200 cells/μl) associated strongly with treatment failure (OR compared with CD4 cell count ≥500: 8.5 [95% CI 2.3-30.7]).

CONCLUSION

Suppressive ART is associated with effective treatment of CIN2+. Early HIV diagnosis and ART are essential for successful CIN2+ treatment.

Alcohol Consumption and Bone Mineral Density in People with HIV and Substance Use Disorder: A Prospective Cohort Study

BACKGROUND

People living with HIV (PLWH) commonly have low bone mineral density (BMD) (low bone mass and osteoporosis) and are at high risk for fractures. Fractures and low BMD are significant causes of morbidity and mortality, increasingly relevant as PLWH age. Alcohol use is common among PLWH and known to affect bone health. The association between alcohol use and changes in BMD among PLWH is not well understood.

METHODS

We conducted a 3.5-year prospective cohort study of 250 PLWH with substance use disorder or ever injection drug use. Annual alcohol consumption was measured as a mean of grams per day of alcohol, mean number of heavy drinking days per month, mean number of days abstinent per month, and any heavy drinking, using the 30-day Timeline Followback method twice each year. The primary outcome was annual change in BMD measured each year by dual energy X-ray absorptiometry in grams per square centimeter (g/cm2 ) at the femoral neck. Additional dependent variables included annual change in total hip and lumbar spine BMD, >6% annual decrease in BMD at any site, and incident fractures in the past year. Regression models adjusted for relevant covariates.

RESULTS

The median age of participants was 50 years. The median duration of HIV infection was 16.5 years and the mean time since antiretroviral therapy initiation was 12.3 years. At study entry, 67% of participants met criteria for low BMD (46% low bone mass, 21% osteoporosis). Median follow-up was 24 months. We found no significant associations between any measure of alcohol consumption and changes in BMD (g/cm2 ) at the femoral neck (adjusted β for g/d of alcohol = -0.0032, p = 0.7487), total hip, or lumbar spine. There was no significant association between any measure of alcohol consumption and >6% annual decrease in BMD at any site, or incident fractures.

CONCLUSIONS

In this sample of PLWH and substance use disorders or ever injection drug use, we detected no association between any of the alcohol measures used in the study and changes in BMD or incident fractures.

Elevated liver stiffness is linked to increased biomarkers of inflammation and immune activation in HIV/hepatitis C virus-coinfected patients

OBJECTIVES

Immune dysregulation is a hallmark of HIV and hepatitis C virus (HCV) infections. We aimed to evaluate the relationship between liver stiffness measurement (LSM) and biomarkers of T-cell activation, bacterial translocation, inflammation, endothelial dysfunction, and coagulopathy in HIV/HCV-coinfected patients.

DESIGN

Cross-sectional study.

METHODS

We studied 238 HIV/HCV-coinfected patients, 32 healthy controls, and 39 HIV-monoinfected patients. Patients were stratified according to LSM into four groups: less than 12.5, 12.5-25, 25-40, and more than 40 kPa. T-cell subsets were measured using flow cytometry and plasma biomarkers using immunoassays.

RESULTS

HIV/HCV-coinfected patients had higher biomarker levels of immune activation in peripheral blood [T-cell activation (CD4CD38 and CD8CD38), bacterial translocation (soluble CD14), inflammation [IL-1b, IL-6, IL-8, IL-18, IFN-γ-inducible protein 10 (IP-10)] endothelial dysfunction [soluble vascular cell adhesion molecule 1 (sVCAM1), soluble intercellular cell adhesion molecule 1 (sICAM1), and soluble tumor necrosis factor receptor 1 (sTNFR1)], and coagulopathy (plasminogen activator inhibitor-1)] than healthy controls and HIV-monoinfected patients. Moreover, in HIV/HCV-coinfected patients, a direct relationship between LSM and immune activation [T-cell activation (CD8CD38 bacterial translocation (lipopolysaccharide), inflammation (IL-8, IP-10), endothelial dysfunction (sVCAM1, sICAM1, and sTNFR1), and coagulopathy (D-dimer)] was found. Subsequently, patients were stratified into different fibrosis stages, finding that patients with cirrhosis who had LSM at least 40 kPa showed higher biomarker values of immune activation [T-cell activation (CD4CD38 and CD8CD38), bacterial translocation (lipopolysaccharide), inflammation (IL-8, IL-6, IP-10), endothelial dysfunction (sVCAM1, sICAM1, and sTNFR1), and coagulopathy (D-dimer)] than patients from the other three groups (<12.5, 12.5-25, and 25-40 kPa).

CONCLUSION

T-cell activation, bacterial translocation, inflammation, endothelial dysfunction, and coagulopathy increased with the severity of liver fibrosis in HIV/HCV-coinfected patients, particularly in patients who had LSM at least 40 kPa.

Vagal dysfunction and small intestinal bacterial overgrowth: novel pathways to chronic inflammation in HIV

OBJECTIVE

Chronic inflammation in HIV-infected individuals drives disease progression and the development of comorbidities, despite viral suppression with combined antiretroviral therapy. Here, we sought evidence that vagal dysfunction, which occurs commonly as part of HIV-associated autonomic neuropathy, could exacerbate inflammation through gastrointestinal dysmotility, small intestinal bacterial overgrowth (SIBO), and alterations in patterns of soluble immune mediators.

DESIGN

This is a cross-sectional observational study.

METHODS

Forty participants on stable combined antiretroviral therapy with gastrointestinal symptoms, and no causes for vagal or gastrointestinal dysfunction other than HIV, underwent autonomic testing, hydrogen/methane breath testing for SIBO, and gastric emptying scintigraphy. A panel of 41 cytokines, high-mobility group box 1, and markers of bacterial translocation (lipopolysaccharide) and monocyte/macrophage activation (sCD14 and sCD163) were tested in plasma.

RESULTS

We found that participants with vagal dysfunction had delayed gastric emptying and higher prevalence of SIBO. SIBO was associated with IL-6, but not sCD14; lipopolysaccharide could not be detected in any participant. We also found alteration of cytokine networks in participants with vagal dysfunction, with stronger and more numerous positive correlations between cytokines. In the vagal dysfunction group, high mobility group box 1 was the only soluble mediator displaying strong negative correlations with other cytokines, especially those cytokines that had numerous other strong positive correlations.

CONCLUSION

The current study provides evidence that the vagal component of HIV-associated autonomic neuropathy is associated with changes in immune and gastrointestinal function in individuals with well treated HIV. Further study will be needed to understand whether therapies targeted at enhancing vagal function could be of benefit in HIV.

From One Syndrome to Many: Incorporating Geriatric Consultation Into HIV Care

Antiretroviral therapy has enabled people to live long lives with human immunodeficiency virus (HIV). As a result, most HIV-infected adults in the United States are >50 years of age. In light of this changing epidemiology, HIV providers must recognize and manage multiple comorbidities and aging-related syndromes. Geriatric principles can help meet this new challenge, as preservation of function and optimization of social and psychological health are relevant to the care of aging HIV-infected adults, even those who are not yet old. Nonetheless, the field is still in its infancy. Although other subspecialties have started to explore the role of geriatricians, little is known about their role in HIV care, and few clinics have incorporated geriatricians. This article introduces basic geriatric nomenclature and principles, examines several geriatric consultation models from other subspecialties, and describes our HIV and Aging clinical program to encourage investigation of best practices for the care of this population.

Bone density, microarchitecture, and tissue quality after 1 year of treatment with tenofovir disoproxil fumarate

OBJECIVE

Bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) is used to assess bone health in HIV patients. DXA measures the amount of mineral, but not other key aspects of bone strength such as bone microarchitecture or bone quality. Trabecular bone score (TBS) and in-vivo microindentation directly measure trabecular microarchitecture and bone tissue quality, respectively. The aim of this study is to measure bone strength properties using these techniques.

RESULTS

Forty naive HIV patients who were going to start antiretroviral therapy (ART), a single pill treatment with elvitegravir/cobicistat, tenofovir disoproxil fumarate (TDF), emtricitavine (FTC) were included. A significant reduction in BMD at spine (-3.25%, P < 0.001) and in femoral neck (-3.82%, P = 0.016) between baseline and 48 weeks of treatment were found. Bone microarchitecture score at the spine, as measured by TBS, also significantly decreased from 1.357 (0.09) to 1.322 (0.09) (-2.5%, P = 0.011) between baseline to 48 weeks of treatment. Microindentation (BMSi) values were significantly higher than at baseline [89.04 (4.2) versus 86.07 (6.1); 3.49%, P < 0.001] after 48 weeks of TDF-based ART treatment, indicating improved bone material properties CONCLUSION:: A significant decrease in BMD and TBS were observed after 1 year of TDF therapy. However, tissue quality significantly improved after 1 year of treatment, suggesting a recovery of bone material properties following the control of the infection despite the significant reduction of BMD. These techniques provide additional and necessary information to DXA about bone health in treated HIV patients, and because of its convenience and feasibility they could be routinely apply to assess bone in clinical practice.

Brief Report: Higher ART Adherence Is Associated With Lower Systemic Inflammation in Treatment-Naive Ugandans Who Achieve Virologic Suppression

BACKGROUND

Residual systemic inflammation persists despite suppressive antiretroviral therapy (ART) and is associated with non-AIDS clinical outcomes. We aimed to evaluate the association between ART adherence and inflammation in Ugandans living with HIV who were predominantly receiving nevirapine-based ART with a thymidine analog backbone and were virologically suppressed by conventional assays.

METHODS

Plasma concentrations of interleukin-6 (IL-6), D-dimer, soluble (s)CD14, sCD163, and the kynurenine/tryptophan ratio, in addition to CD8 T-cell activation, were measured at baseline and 6 months after ART initiation in treatment-naive adults who achieved an undetectable plasma HIV RNA (<400 copies/mL) at their 6-month visit. Adherence was measured through medication event monitoring system and calculated as the ratio of observed/prescribed device openings per participant. We fit adjusted linear regression models to estimate the association between ART adherence and the log-transformed plasma concentrations of inflammatory biomarkers.

RESULTS

We evaluated 282 participants (median age, 35 years; 70% women). The median (interquartile range) adherence was 93% (84-98). In the adjusted analyses, for every 10% increase in average ART adherence, we found a 15% [P < 0.0001; 95% confidence interval (CI), -21.0 to -7.9], 11% (P = 0.017; 95% CI, -18.3 to -2.0), and 3% (P = 0.028; 95% CI, -5.0 to -0.3) decrease in IL-6, D-dimer, and sCD14, respectively.

CONCLUSIONS

Higher ART adherence was associated with lower levels of biomarkers of inflammation, immune activation, and coagulopathy among Ugandans living with HIV who achieved viral suppression shortly after ART initiation. This suggests that ART adherence could have biological consequences beyond viral suppression. Whether ART adherence optimization in virologically suppressed individuals could reduce residual inflammation remains unknown.

Sex Differences in HIV Infection

PURPOSE OF REVIEW

This review will outline the multilevel effects of biological sex on HIV acquisition, pathogenesis, treatment response, and prospects for cure. Potential mechanisms will be discussed along with future research directions.

RECENT FINDINGS

HIV acquisition risk is modified by sex hormones and the vaginal microbiome, with the latter acting through both inflammation and local metabolism of pre-exposure prophylaxis drugs. Female sex associates with enhanced risk for non-AIDS morbidities including cardiovascular and cerebrovascular disease, suggesting different inflammatory profiles in men and women. Data from research on HIV cure points to sex differences in viral reservoir dynamics and a direct role for sex hormones in latency maintenance. Biological sex remains an important variable in determining the risk of HIV infection and subsequent viral pathogenesis, and emerging data suggest sex differences relevant to curative interventions. Recruitment of women in HIV clinical research is a pathway to both optimize care for women and to identify novel therapeutics for use in both men and women.

Management of Long-Term Complications of HIV Disease: Focus on Cardiovascular Disease

HIV-infected individuals on effective antiretroviral therapy experience a number of non-AIDS noncommunicable diseases, such as cardiovascular disease, more frequently than uninfected individuals. Common pathways for such diseases are chronic immune activation and inflammation, including the prolonged inflammation associated with lower nadir CD4+ cell count. Prevention and treatment of non-AIDS conditions include treatment of traditional risk factors, lifestyle interventions, earlier initiation of antiretroviral therapy, and potentially therapies specifically targeting inflammation and immune activation (eg, statins). This article summarizes a presentation by Judith S. Currier, MD, at the IAS-USA continuing education program, Improving the Management of HIV Disease, held in New York, New York, in February 2017.

Effects of HIV infection and ART on phenotype and function of circulating monocytes, natural killer, and innate lymphoid cells

HIV infection causes upregulation of markers of inflammation, immune activation and apoptosis of host adaptive, and innate immune cells particularly monocytes, natural killer (NK) and innate lymphoid cells (ILCs). Although antiretroviral therapy (ART) restores CD4 T-cell counts, the persistent aberrant activation of monocytes, NK and ILCs observed likely contributes to the incomplete recovery of T-cell effector functions. A better understanding of the effects of HIV infection and ART on the phenotype and function of circulating monocytes, NK, and ILCs is required to guide development of novel therapeutic interventions to optimize immune recovery.

Vitamin D supplementation decreases immune activation and exhaustion in HIV-1-infected youth

BACKGROUND

Heightened immune activation and exhaustion drive HIV disease progression and comorbidities. Vitamin D has pleiotropic immunomodulatory effects, but little is known about the effects of supplementation in HIV. Our study investigates changes in immune activation and exhaustion markers after 12 months of supplementation in virologically suppressed HIV-infected youth with vitamin D insufficiency.

METHODS

This is a randomized, active-control, double-blind trial investigating with three different vitamin D3 doses (18,000 [standard/active-control dose], 60,000 [moderate dose] and 120,000 IU/month [high dose]) in 8-25-year-old HIV-infected youth on combination antiretroviral therapy with baseline serum 25-hydroxyvitamin D (25(OH)D) concentrations ≤30 ng/ml. Only subjects (n=51) who maintained an undetectable HIV-1 RNA over the 12-month study period were included in this analysis.

RESULTS

Baseline serum 25(OH)D concentrations and immune activation/exhaustion markers were not different between groups. By 12 months, 25(OH)D increased significantly within each dosing group with the greatest increase and most sustained concentrations ≥30 ng/ml in the high-dose group. Overall, all measured markers decreased with CD4 activation (CD4+CD38+HLA-DR+), CD8 activation (CD8+CD38+HLA-DR+), CD4 exhaustion (CD4+CD38+HLA-DR+PD1+) and inflammatory monocytes (CD14+CD16+) reaching statistical significance. When analysed separately, there were no significant decreases in the moderate- or standard-dose groups, but CD4 and CD8 activation and inflammatory monocytes decreased significantly in the high-dose group.

CONCLUSIONS

Vitamin D supplementation decreased markers of T-cell activation/exhaustion and monocyte activation in HIV-infected youth, with subjects given the highest dose (120,000 IU/month) showing the greatest decreases. These data suggest that high-dose vitamin D supplementation may attenuate immune activation and exhaustion, and serve as adjuvant therapy to antiretroviral therapy in HIV. ClinicalTrials.gov identifier: NCT01523496.

HIV Persistence on Antiretroviral Therapy and Barriers to a Cure

HIV persists within the body despite successful suppression of virus replication with antiretroviral therapy (ART). HIV lurks in latent and active reservoirs, leading to rebound of virus spread if ART is interrupted. The latent HIV reservoir is a natural consequence of the life cycle of HIV, with integration of HIV into the genomes of cells that are or later enter the resting state, resulting in transcriptionally quiescent provirus. Resting CD4 T cells comprise the majority of the latent reservoir, although new evidence points to additional, smaller cellular reservoirs of latent HIV. An alternate, so-called active reservoir of HIV also exists within cells such as those found the B cell follicle of lymph nodes, where expression of HIV RNA can be found, again despite the full suppression of viremia and viral replication. Multiple factors such as the degree of virus exposure, timing of ART, and host factors can influence the size and characteristics of the HIV reservoir. Constructing effective strategies for HIV eradication and measuring their impact will require a sophisticated knowledge of the HIV reservoir.

Association of Suboptimal Antiretroviral Therapy Adherence With Inflammation in Virologically Suppressed Individuals Enrolled in the SMART Study

Suboptimal (ie, <100%) antiretroviral therapy (ART) adherence has been associated with heightened inflammation in cohort studies, even among people with virologic suppression. We aimed to evaluate this association among participants in the Strategies for Management of Antiretroviral Therapy (SMART) study who had virologic suppression (HIV-1 VL < 200 copies/mL) at enrollment. Based on self-reported adherence (7-day recall), plasma concentrations of interleukin 6 and D-dimer were 9% (95% confidence interval [CI], 1%-18%; P = .02) and 11% (95% CI, 1%-22%; P = .03) higher in participants who reported suboptimal vs 100% adherence, respectively. These findings confirm previous observations and support the hypothesis that suboptimal ART adherence, even in the context of virologic suppression, may have significant biological consequences. ClinicalTrials.gov number NCT00027352.

Inflammation-Related Morbidity and Mortality Among HIV-Positive Adults: How Extensive Is It?

OBJECTIVE

To determine the rate of grade 4, potentially life-threatening events not attributable to AIDS, cardiovascular disease (CVD), or non-AIDS cancer among participants on antiretroviral therapy and to describe associations of these events with interleukin-6 (IL-6) and D-dimer.

DESIGN

Cohort study.

METHODS

HIV-infected participants on antiretroviral therapy (N = 3568) with an HIV-RNA level ≤ 500 copies/mL were followed for grade 4, AIDS, CVD, non-AIDS cancer, and all-cause mortality events. Grade 4 events were further classified masked to biomarker levels as reflecting chronic inflammation-related disease (ChrIRD) or not (non-ChrIRD). Associations of baseline IL-6 and D-dimer with events were studied using Cox models.

RESULTS

Over a median follow-up of 4.3 years, 339 participants developed a grade 4 event (22.9 per 1000 person-years); 165 participants developed a ChrIRD grade 4 event (10.7 per 1000 person-years). Grade 4 events were more common than AIDS (54 participants), CVD (132), and non-AIDS cancer (80) events, any of which developed in 252 participants (17.1 per 1000 person-years). Grade 4 and AIDS events were associated with similar risks of death. Higher IL-6 [hazard ratio (HR) = 1.19 per doubling of biomarker; P = 0.003] and D-dimer (HR = 1.23; P < 0.001) levels were associated with an increased risk of grade 4 events. IL-6 associations were stronger for ChrIRD (HR = 1.38; P < 0.001) than non-ChrIRD grade 4 events (HR = 1.11; P = 0.21).

CONCLUSIONS

Morbidity and mortality associated with activation of inflammatory and coagulation pathways include conditions other than AIDS, CVD, and non-AIDS cancer events. Effective inflammation-dampening interventions could greatly affect the health of people with HIV.

Sex Differences in Select Non-communicable HIV-Associated Comorbidities: Exploring the Role of Systemic Immune Activation/Inflammation

PURPOSE OF THE REVIEW

The goals of this review are to (1) explore HIV-associated cardiovascular disease (CVD), neurocognitive impairment, and non-AIDS-defining cancers (NADC) as heterogeneous model disease states fuelled in part by systemic immune activation/inflammation; (2) consider sex differences in the epidemiology of these diseases in both high-resource and lower-resource settings; and (3) examine biological and environmental factors which may contribute to heightened systemic immune activation/inflammation specifically among women living with HIV (WLHIV).

RECENT FINDINGS

The observation that WLHIV have higher levels of systemic immune activation/inflammation than men living with HIV (MLHIV) may be relevant to sex differences in select non-communicable HIV-associated comorbidities. Heightened systemic immune activation among WLHIV may be influenced by sex-specific responses to the virus and to immunomodulatory agents, as well as by behavioral choices/comorbid conditions and perturbations in the hypothalamic-pituitary-gonadal axis. Additional research is needed to elucidate region-specific drivers of heightened systemic immune activation/inflammation among WLHIV and to determine whether WLHIV who present with one immune-mediated HIV-associated comorbidity (e.g., cognitive impairment) may be at increased risk for another (e.g., CVD, NADC). This kind of research would facilitate improved risk prediction for non-communicable HIV-associated comorbidities among WLHIV and the development of targeted immunomodulatory prevention strategies.

Changes in inflammatory/cardiac markers of HIV positive patients

HIV replication promotes atherogenesis and participates in the immune response to the virus, thereby influencing the inflammatory profile. These changes may, in turn, contribute to the risk of cardiovascular diseases with involvement of platelets. However, adenine nucleotides and nucleosides involved in thromboregulation and modulation of immune response may therefore be affected by these alterations.

OBJECTIVES

This study sought to evaluate the profile of pro and anti-inflammatory cytokines (IL-10, IL-6, IL-17, TNF, IL-4, IL-2 and IFN-gamma), cardiac markers (troponin, CK, CK MB, LDH, CRP) in HIV-positive patients and assess the in vitro effect of antiretroviral therapy on the activities of ectonucleotidases (E-NTPDase and E-5'-nucleotidase) in human platelets.

DESIGN AND METHODS

Blood samples were obtained from ten HIV positive patients at the Infectious Disease Clinic of the University Hospital of Santa Maria, Brazil and ten HIV negative individuals (control group) for this study.

RESULTS

The results revealed that there were significant (P < 0.05) increases in serum levels of IL-6 and IFN-gamma with no significant (P > 0.05) changes in the serum levels of the cardiac markers investigated (CK, CK-MB, troponin, LDH and CRP). In addition, the ectonucleotidases (E-NTPDase and E-5'-nucleotidase) activities were not altered (P > 0.05) in human platelets when incubated with different antiretroviral drugs in vitro.

CONCLUSIONS

The results of this study suggest that, despite successful treatment, a proinflammatory state is not altered in HIV patients, and that antiretroviral therapy per se does not change the purinergic profile.

Reevaluation of immune activation in the era of cART and an aging HIV-infected population

Biological aging is associated with immune activation (IA) and declining immunity due to systemic inflammation. It is widely accepted that HIV infection causes persistent IA and premature immune senescence despite effective antiretroviral therapy and virologic suppression; however, the effects of combined HIV infection and aging are not well defined. Here, we assessed the relationship between markers of IA and inflammation during biological aging in HIV-infected and -uninfected populations. Antibody response to seasonal influenza vaccination was implemented as a measure of immune competence and relationships between IA, inflammation, and antibody responses were explored using statistical modeling appropriate for integrating high-dimensional data sets. Our results show that markers of IA, such as coexpression of HLA antigen D related (HLA-DR) and CD38 on CD4+ T cells, exhibit strong associations with HIV infection but not with biological age. Certain variables that showed a strong relationship with aging, such as declining naive and CD38+ CD4 and CD8+ T cells, did so regardless of HIV infection. Interestingly, the variable of biological age was not identified in a predictive model as significantly impacting vaccine responses in either group, while distinct IA and inflammatory variables were closely associated with vaccine response in HIV-infected and -uninfected populations. These findings shed light on the most relevant and persistent immune defects during virological suppression with 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.

Pathogenesis of infections in HIV-infected individuals: insights from primary immunodeficiencies

Following infection with almost any given microorganism other than an emerging pathogen, only a minority of individuals develop life-threatening clinical disease, implying that these individuals have some form of immunodeficiency. A growing number of inherited and acquired immunodeficiencies have been deciphered over the last 50 years. HIV infection is probably the best-known acquired immunodeficiency. It emerged about 40 years ago and precipitates various severe infections, the occurrence of which is associated with a fall in circulating CD4⁺ T cells. However, despite the strength of this correlation, infection rates differ between patients with similar levels and durations of CD4⁺ T lymphopenia in the presence or absence of antiretroviral treatment. Moreover, a few infections seem to be less dependent on total CD4⁺ T-cell levels. The fine detail of the mechanisms underlying these infections is unknown. We discuss here how studies of the human genetics and immunology of some of these infections in patients with primary immunodeficiencies (PIDs) have provided unique insights into their molecular and cellular basis. Defects of specific CD4⁺ Th-cell subsets account for some of these infections, as best exemplified by Th1* for mycobacteriosis and Th17 for candidiasis. PIDs are individually rare, but collectively much more common than initially thought, with new disorders being discovered at an ever-increasing pace and a global prevalence worldwide approaching that of HIV infection. Studies of known and new PIDs should make it possible to dissect the pathogenesis of most human infections at an unprecedented level of molecular and cellular precision. The predictive, preventive, and therapeutic implications of studies of immunity to infection in PIDs may extend to HIV-infected patients and patients with infectious diseases in other settings.

Early and Delayed Antiretroviral Therapy Results in Comparable Reductions in CD8+ T Cell Exhaustion Marker Expression

In untreated HIV infection, CD8+ T cell exhaustion (i.e., decreased proliferative and effector capacity) is associated with high levels of expression of coinhibitory receptors, including PD-1, T cell immunoreceptor with Ig and ITIM domains (TIGIT), CD160, and 2B4. This is evident for both HIV-specific and non-HIV-specific CD8+ T cells. Antiretroviral therapy (ART) initiated during chronic infection decreases but may not completely normalize the expression of such "exhaustion markers." Compared to initiation of ART later in the course of disease, initiation soon after infection reduces some parameters of chronic inflammation and adaptive immune dysfunction. However, it is not known if Early ART (e.g., initiated within the first 6 months after HIV infection) versus Delayed ART (e.g., initiated during chronic infection) preferentially reduces expression of exhaustion markers. We evaluated exhaustion marker expression on subsets of circulating effector and memory CD8+ T cells at longitudinal pre- and post-ART (2 and 5 years on ART) time points from n = 19 (Early ART) and n = 23 (Delayed ART) individuals. Before ART, TIGIT and CD160 were expressed on a statistically significantly higher proportion of effector and transitional memory cells from individuals in the Delayed ART group: the timing of ART initiation, however, did not consistently affect the expression of the exhaustion markers once viral suppression was achieved. Understanding which factors do and do not regulate aspects of CD8+ T cell exhaustion, including the expression of exhaustion markers, is critical to inform the rational design of CD8+ T cell-based therapies to treat HIV, for which CD8+ T cell exhaustion remains an important barrier to efficacy.

Basic science and pathogenesis of ageing with HIV: potential mechanisms and biomarkers

: The increased prevalence of age-related comorbidities and mortality is worrisome in ageing HIV-infected patients. Here, we aim to analyse the different ageing mechanisms with regard to HIV infection. Ageing results from the time-dependent accumulation of random cellular damage. Epigenetic modifications and mitochondrial DNA haplogroups modulate ageing. In antiretroviral treatment-controlled patients, epigenetic clock appears to be advanced, and some haplogroups are associated with HIV infection severity. Telomere shortening is enhanced in HIV-infected patients because of HIV and some nucleoside analogue reverse transcriptase inhibitors. Mitochondria-related oxidative stress and mitochondrial DNA mutations are increased during ageing and also by some nucleoside analogue reverse transcriptase inhibitors. Overall, increased inflammation or 'inflammageing' is a major driver of ageing and could result from cell senescence with secreted proinflammatory mediators, altered gut microbiota, and coinfections. In HIV-infected patients, the level of inflammation and innate immunity activation is enhanced and related to most comorbidities and to mortality. This status could result, in addition to age, from the virus itself or viral protein released from reservoirs, from HIV-enhanced gut permeability and dysbiosis, from antiretroviral treatment, from frequent cytomegalovirus and hepatitis C virus coinfections, and also from personal and environmental factors, as central fat accumulation or smoking. Adaptive immune activation and immunosenescence are associated with comorbidities and mortality in the general population but are less predictive in HIV-infected patients. Biomarkers to evaluate ageing in HIV-infected patients are required. Numerous systemic or cellular inflammatory, immune activation, oxidative stress, or senescence markers can be tested in serum or peripheral blood mononuclear cells. The novel European Study to Establish Biomarkers of Human Ageing MARK-AGE algorithm, evaluating the biological age, is currently assessed in HIV-infected patients and reveals an advanced biological age. Some enhanced inflammatory or innate immune activation markers are interesting but still not validated for the patient's follow-up. To be able to assess patients' biological age is an important objective to improve their healthspan.

Immune Reconstitution Inflammatory Syndrome (IRIS): What pathologists should know

Antiretroviral therapy has significantly improved the quality and length of life for those patients able to access effective and sustained treatment. The resulting restoration of the immune response is associated with a change in the clinical presentation of opportunistic infections, and the histologic reaction to pathogens. A complex combination of alterations in host response across the stages of HIV infection has been documented over the past 3 decades. The defects are seen in both acute and chronic phases of inflammation and involve innate and adaptive immunity. In advanced stages of HIV infection, the marked disruption of lymphoid tissue and loss of follicular dendritic cells limits the host's ability to process antigen and mount specific responses to pathogens. There are qualitative and quantitative defects in CD4 T cells due to HIV infection. The resulting indirect effects include loss of cytokine production, dysregulation of B-cell function, loss of cellular mediated immunity and "holes" in the immunologic repertoire that may not be restored with the use of antiretroviral therapy. Immune reconstitution allows the host to respond to and control infection, but a significant number of patients will have atypical inflammatory syndromes during the recovery period. We briefly discuss the impact of HIV infection on the immune system and give an overview of the spectrum of conditions attributed to the Immune Reconstitution Inflammatory syndrome (IRIS).

The nature and consequences of cognitive deficits among tobacco smokers with HIV: a comparison to tobacco smokers without HIV

HIV-infected smokers lose more years of life to tobacco-related disease than HIV. Since neurocognitive deficits are common among those with HIV and are associated with smoking persistence, these deficits may be a unique barrier to smoking cessation among HIV-infected smokers. Documenting unique differences in and correlates of cognition among HIV-infected smokers is a critical step towards developing a population-specific tobacco cessation treatment. We compared neurocognitive function between HIV-infected (n = 103) and HIV-uninfected smokers (n = 70), accounting for demographic and smoking-related variables. We also evaluated whether HIV-related health outcomes (e.g., CD4 count, viral load, depression ratings, quality of life [QoL]) and HAART adherence were associated with cognition. Participants completed neurocognitive tasks (N-back and Continuous Performance Task [CPT]) measuring working memory, attention, and processing speed, and intra-individual variability. Stepwise regression models were conducted and validated with resampling techniques. HIV-infected smokers performed worse than HIV-uninfected smokers on working memory, processing speed, and intra-individual variability (all p < 0.01). ROC analysis for the model including cognitive measures demonstrated 85% area under the curve, which indicates "good prediction" for distinguishing between HIV-infected and HIV-uninfected smokers. This was a significant improvement over the model including demographic and smoking-related variables only (p = 0.0003). Among HIV-infected smokers, neurocognitive performance was negatively associated with QoL and depression ratings. Smoking cessation interventions for HIV-infected smokers should consider cognitive neurorehabilitation as a potential strategy to decrease the likelihood of nicotine relapse and decrease tobacco-related morbidity in this population.

Immunologic Pathways That Predict Mortality in HIV-Infected Ugandans Initiating Antiretroviral Therapy

The plasma kynurenine/tryptophan (KT) ratio, a marker of adaptive immune defects, strongly predicts mortality during treated human immunodeficiency virus (HIV) disease in Ugandans as compared to US-based populations. Here, the KT ratio and T-cell and plasma biomarkers of immune activation were measured among 535 HIV-infected Ugandans prior to ART initiation and at month 6 of viral suppression. The month 6 KT ratio (adjusted hazard ratio [aHR], 2.74), soluble CD14 level (aHR, 2.32), interleukin 6 level (aHR, 2.34), and D-dimer level (aHR, 1.95) were associated with mortality occurring ≥6 months after ART initiation. The KT ratio remained significantly predictive of mortality even after adjustment for the additional biomarkers, suggesting an independent contribution to clinical outcomes in resource-limited settings.