Relationship between CD4 T cell turnover, cellular differentiation and HIV persistence during ART

The precise role of CD4 T cell turnover in maintaining HIV persistence during antiretroviral therapy (ART) has not yet been well characterized. In resting CD4 T cell subpopulations from 24 HIV-infected ART-suppressed and 6 HIV-uninfected individuals, we directly measured cellular turnover by heavy water labeling, HIV reservoir size by integrated HIV-DNA (intDNA) and cell-associated HIV-RNA (caRNA), and HIV reservoir clonality by proviral integration site sequencing. Compared to HIV-negatives, ART-suppressed individuals had similar fractional replacement rates in all subpopulations, but lower absolute proliferation rates of all subpopulations other than effector memory (TEM) cells, and lower plasma IL-7 levels (p = 0.0004). Median CD4 T cell half-lives decreased with cell differentiation from naïve to TEM cells (3 years to 3 months, p<0.001). TEM had the fastest replacement rates, were most highly enriched for intDNA and caRNA, and contained the most clonal proviral expansion. Clonal proviruses detected in less mature subpopulations were more expanded in TEM, suggesting that they were maintained through cell differentiation. Earlier ART initiation was associated with lower levels of intDNA, caRNA and fractional replacement rates. In conclusion, circulating integrated HIV proviruses appear to be maintained both by slow turnover of immature CD4 subpopulations, and by clonal expansion as well as cell differentiation into effector cells with faster replacement rates.

Circulating CD30+CD4+ T Cells Increase Before Human Immunodeficiency Virus Rebound After Analytical Antiretroviral Treatment Interruption

BACKGROUND

Identification of nonviral markers of human immunodeficiency virus (HIV) infection that increase before viral rebound during analytical treatment interruption (ATI) may affect HIV persistence research. We previously showed that HIV ribonucleic acid (RNA) is enriched in CD30+CD4+ T cells in many individuals. Here, we studied CD30+CD4+ T-cell dynamics before ATI, during ATI (before detectable plasma RNA), and after HIV rebound.

METHODS

Peripheral blood mononuclear cells from 23 participants collected longitudinally from 5 Adult AIDS Clinical Trials Group studies incorporating ATI were included in this study. Flow cytometric characterization of expression of CD30 and markers of T-cell activation and exhaustion were performed along with HIV-1 RNA and deoxyribonucleic acid quantification and measurement of soluble plasma CD30 and CD30 ligand.

RESULTS

The percentage of CD4+ T cells expressing CD30 significantly increased from pre-ATI to postinterruption time points before detectible viremia (1.65 mean relative increase, P = .005). Seventy-seven percent of participants experienced an increase in CD30+ cells before viral rebound. In contrast, there were no significant differences between pre-ATI and postinterruption pre-rebound time points in percentages of lymphocytes expressing CD69, CD38/HLA-DR, or PD-1 until after HIV recrudescence.

CONCLUSIONS

CD30 may be a surrogate marker of early replication or viral transcriptional activity before detection by routine peripheral blood sampling.

Accumulation of HIV-1 Drug Resistance Mutations and Methamphetamine Use

BACKGROUND

Antiretroviral therapy (ART) non-adherence and methamphetamine use are associated with higher HIV drug resistance prevalence. How they affect drug resistance mutations accumulation is less studied.

OBJECTIVE

We assessed factors associated with drug resistance mutations accumulation.

METHODS

We evaluated HIV chronically-infected patients from a clinic-based research cohort on first-line ART regimens with genotype results within 30 days of baseline. Methamphetamine use and ART adherence were self-reported at each study visit. High ART adherence was defined as 0-5% missed doses in the last 30 days.

RESULTS

One-hundred twenty-five patients contributed 496 study visits. At baseline, 81% of patients reported high ART adherence; 90% reported no methamphetamine use in the prior 4 months, 8% used monthly or less and 2% used daily or weekly. Methamphetamine users and non-users had similarly high ART adherence (p=0.93). Adjusted incidence rate ratio (aIRR) of drug resistance mutations accumulation was 2.04 (95% CI 0.64, 6.46) for daily/weekly users and 1.71 (95% CI 0.66, 4.42) for patients with monthly or less users, compared to non-users. aIRR was 0.71 (95% CI 0.44, 1.15) with >5-10% missed ART doses and 1.21 (95% CI 0.80, 1.83) with >10% missed doses compared to 0-5% missed doses.

CONCLUSION

We found no strong evidence for the effect of methamphetamine use and ART adherence on drug resistance mutations accumulation. Research cohort patients may have been more engaged in care and treatment adherent than non-cohort patients. Our findings suggest methamphetamine use might not lead to treatment failure among HIV patients who are otherwise engaged in care.

NIH Workshop on HIV-Associated Comorbidities, Coinfections, and Complications: Summary and Recommendation for Future Research

BACKGROUND

With potent antiretroviral therapy and simplified regimens, people living with HIV (PWH) are achieving near-normal lifespans but not necessarily a normal health span or healthy aging. PWH have a higher than expected risk of developing a number of non-AIDS comorbidities, coinfections, and complications (CCC), often against a background of stigma, poverty, and isolation.

SETTING

To gain a better understanding of research needs for HIV-associated CCC, the NIH convened a 2-day workshop (HIV-associated CCC, or HIV ACTION).

METHODS

A cross-institute NIH planning committee identified 6 key research areas: epidemiology and population research, pathogenesis and basic science research, clinical research, implementation science research, syndemics research and international research in low and middle income countries. Investigators were selected to lead working groups (WGs) to assess the state-of-the-art and identify 3-5 priority areas in each field before the workshop. A 2-day program at the NIH was developed which included presentations by invited experts and WG members.

RESULTS

Over 400 participants attended the workshop. After general and individual WG discussions, the most pressing gaps, questions, or proposed action items were identified. Priority lists of pressing research issues were presented by cochairs of each WG. A detailed report is posted at the NHLBI website. This article reports the streamlined priority list and a summary of WG discussions to inform investigators of current priorities in the field.

CONCLUSION

Collaborative efforts of many disciplines are needed to improve the health and wellbeing of PWH. Several common themes emerged across WG representing potential priorities for investigators and recommendations for the NIH.

Shared Mechanisms Govern HIV Transcriptional Suppression in Circulating CD103+ and Gut CD4+ T Cells

Latent HIV infection is the main barrier to cure, and most HIV-infected cells reside in the gut, where distinct but unknown mechanisms may promote viral latency. Transforming growth factor β (TGF-β), which induces the expression of CD103 on tissue-resident memory T cells, has been implicated in HIV latency. Using CD103 as a surrogate marker to identify cells that have undergone TGF-β signaling, we compared the HIV RNA/DNA contents and cellular transcriptomes of CD103+ and CD103- CD4 T cells from the blood and rectum of HIV-negative (HIV-) and antiretroviral therapy (ART)-suppressed HIV-positive (HIV+) individuals. Like gut CD4+ T cells, circulating CD103+ cells harbored more HIV DNA than did CD103- cells but transcribed less HIV RNA per provirus. Circulating CD103+ cells also shared a gene expression profile that is closer to that of gut CD4 T cells than to that of circulating CD103- cells, with significantly lower expression levels of ribosomal proteins and transcriptional and translational pathways associated with HIV expression but higher expression levels of a subset of genes implicated in suppressing HIV transcription. These findings suggest that blood CD103+ CD4 T cells can serve as a model to study the molecular mechanisms of HIV latency in the gut and reveal new cellular factors that may contribute to HIV latency.IMPORTANCE The ability of HIV to establish a reversibly silent, "latent" infection is widely regarded as the main barrier to curing HIV. Most HIV-infected cells reside in tissues such as the gut, but it is unclear what mechanisms maintain HIV latency in the blood or gut. We found that circulating CD103+ CD4+ T cells are enriched for HIV-infected cells in a latent-like state. Using RNA sequencing (RNA-seq), we found that CD103+ T cells share a cellular transcriptome that more closely resembles that of CD4+ T cells from the gut, suggesting that they are homing to or from the gut. We also identified the cellular genes whose expression distinguishes gut CD4+ or circulating CD103+ T cells from circulating CD103- T cells, including some genes that have been implicated in HIV expression. These genes may contribute to latent HIV infection in the gut and may serve as new targets for therapies aimed at curing HIV.

Genetic architecture of cardiometabolic risks in people living with HIV

BACKGROUND

Advances in antiretroviral therapies have greatly improved the survival of people living with human immunodeficiency virus (HIV) infection (PLWH); yet, PLWH have a higher risk of cardiovascular disease than those without HIV. While numerous genetic loci have been linked to cardiometabolic risk in the general population, genetic predictors of the excessive risk in PLWH are largely unknown.

METHODS

We screened for common and HIV-specific genetic variants associated with variation in lipid levels in 6284 PLWH (3095 European Americans [EA] and 3189 African Americans [AA]), from the Centers for AIDS Research Network of Integrated Clinical Systems cohort. Genetic hits found exclusively in the PLWH cohort were tested for association with other traits. We then assessed the predictive value of a series of polygenic risk scores (PRS) recapitulating the genetic burden for lipid levels, type 2 diabetes (T2D), and myocardial infarction (MI) in EA and AA PLWH.

RESULTS

We confirmed the impact of previously reported lipid-related susceptibility loci in PLWH. Furthermore, we identified PLWH-specific variants in genes involved in immune cell regulation and previously linked to HIV control, body composition, smoking, and alcohol consumption. Moreover, PLWH at the top of European-based PRS for T2D distribution demonstrated a > 2-fold increased risk of T2D compared to the remaining 95% in EA PLWH but to a much lesser degree in AA. Importantly, while PRS for MI was not predictive of MI risk in AA PLWH, multiethnic PRS significantly improved risk stratification for T2D and MI.

CONCLUSIONS

Our findings suggest that genetic loci involved in the regulation of the immune system and predisposition to risky behaviors contribute to dyslipidemia in the presence of HIV infection. Moreover, we demonstrate the utility of the European-based and multiethnic PRS for stratification of PLWH at a high risk of cardiometabolic diseases who may benefit from preventive therapies.

Phenotypic analysis of the unstimulated in vivo HIV CD4 T cell reservoir

The latent reservoir is a major barrier to HIV cure. As latently infected cells cannot be phenotyped directly, the features of the in vivo reservoir have remained elusive. Here, we describe a method that leverages high-dimensional phenotyping using CyTOF to trace latently infected cells reactivated ex vivo to their original pre-activation states. Our results suggest that, contrary to common assumptions, the reservoir is not randomly distributed among cell subsets, and is remarkably conserved between individuals. However, reservoir composition differs between tissues and blood, as do cells successfully reactivated by different latency reversing agents. By selecting 8-10 of our 39 original CyTOF markers, we were able to isolate highly purified populations of unstimulated in vivo latent cells. These purified populations were highly enriched for replication-competent and intact provirus, transcribed HIV, and displayed clonal expansion. The ability to isolate unstimulated latent cells from infected individuals enables previously impossible studies on HIV persistence.

Abnormal Levels of Some Biomarkers of Immune Activation Despite Very Early Treatment of Human Immunodeficiency Virus

BACKGROUND

Despite early antiretroviral therapy (ART), ART-suppressed people with human immunodeficiency virus (HIV) (PWH) remain at higher risk for infections and infection-related cancers than the general population. The immunologic pathways that remain abnormal in this setting, potentially contributing to these complications, are unclear.

METHODS

ART-suppressed PWH and HIV-negative controls, all cytomegalovirus seropositive and enriched for HIV risk factors, were sampled from an influenza vaccine responsiveness study. PWH were stratified by timing of ART initiation (within 6 months of infection [early ART] vs later) and nadir CD4+ T-cell count among later initiators. Between-group differences in kynurenine-tryptophan (KT) ratio, interferon-inducible protein 10, soluble CD14 and CD163, soluble tumor necrosis factor receptor 2, interleukin 6, and soluble urokinase plasminogen activator receptor were assessed after confounder adjustment.

RESULTS

Most participants (92%) were male, reflecting the demographics of early-ART initiators in San Francisco. Most biomarkers were higher among later-ART initiators. Participants in the early-ART group achieved near-normal soluble tumor necrosis factor receptor 2, interleukin 6, and soluble urokinase plasminogen activator receptor levels, but substantially higher KT ratio than those without HIV after confounder adjustment (P = .008). Soluble CD14, soluble CD163, and interferon-inducible protein 10 trended similarly.

CONCLUSIONS

While early-ART initiators restore near-normal levels of many inflammatory markers, the kynurenine pathway of tryptophan catabolism remains abnormally high. Because this pathway confers adaptive immune defects and predicts tuberculosis and cancer progression, this it may contribute to persistent risks of these complications in this setting.

Variation in HIV-1 Nef function within and among viral subtypes reveals genetically separable antagonism of SERINC3 and SERINC5

HIV Nef counteracts cellular host restriction factors SERINC3 and SERINC5, but our understanding of how naturally occurring global Nef sequence diversity impacts these activities is limited. Here, we quantify SERINC3 and SERINC5 internalization function for 339 Nef clones, representing the major pandemic HIV-1 group M subtypes A, B, C and D. We describe distinct subtype-associated hierarchies for Nef-mediated internalization of SERINC5, for which subtype B clones display the highest activities on average, and of SERINC3, for which subtype B clones display the lowest activities on average. We further identify Nef polymorphisms that modulate its ability to counteract SERINC proteins, including substitutions in the N-terminal domain that selectively impair SERINC3 internalization. Our findings demonstrate that the SERINC antagonism activities of HIV Nef differ markedly among major viral subtypes and between individual isolates within a subtype, suggesting that variation in these functions may contribute to global differences in viral pathogenesis.

Differential Vpu-Mediated CD4 and Tetherin Downregulation Functions among Major HIV-1 Group M Subtypes

Downregulation of BST-2/tetherin and CD4 by HIV-1 viral protein U (Vpu) promotes viral egress and allows infected cells to evade host immunity. Little is known however about the natural variability in these Vpu functions among the genetically diverse viral subtypes that contribute to the HIV-1 pandemic. We collected Vpu isolates from 332 treatment-naive individuals living with chronic HIV-1 infection in Uganda, Rwanda, South Africa, and Canada. Together, these Vpu isolates represent four major HIV-1 group M subtypes (A [n = 63], B [n = 84], C [n = 94], and D [n = 59]) plus intersubtype recombinants and uncommon strains (n = 32). The ability of each Vpu clone to downregulate endogenous CD4 and tetherin was quantified using flow cytometry following transfection into an immortalized T-cell line and compared to that of a reference Vpu clone derived from HIV-1 subtype B NL4.3. Overall, the median CD4 downregulation function of natural Vpu isolates was similar to that of NL4.3 (1.01 [interquartile range {IQR}, 0.86 to 1.18]), while the median tetherin downregulation function was moderately lower than that of NL4.3 (0.90 [0.79 to 0.97]). Both Vpu functions varied significantly among HIV-1 subtypes (Kruskal-Wallis P < 0.0001). Specifically, subtype C clones exhibited the lowest CD4 and tetherin downregulation activities, while subtype D and B clones were most functional for both activities. We also identified Vpu polymorphisms associated with CD4 or tetherin downregulation function and validated six of these using site-directed mutagenesis. Our results highlight the marked extent to which Vpu function varies among global HIV-1 strains, raising the possibility that natural variation in this accessory protein may contribute to viral pathogenesis and/or spread.IMPORTANCE The HIV-1 accessory protein Vpu enhances viral spread by downregulating CD4 and BST-2/tetherin on the surface of infected cells. Natural variability in these Vpu functions may contribute to HIV-1 pathogenesis, but this has not been investigated among the diverse viral subtypes that contribute to the HIV-1 pandemic. In this study, we found that Vpu function differs significantly among HIV-1 subtypes A, B, C, and D. On average, subtype C clones displayed the lowest ability to downregulate both CD4 and tetherin, while subtype B and D clones were more functional. We also identified Vpu polymorphisms that associate with functional differences among HIV-1 isolates and subtypes. Our study suggests that genetic diversity in Vpu may play an important role in the differential pathogenesis and/or spread of HIV-1.

Lower Pretreatment Gut Integrity Is Independently Associated With Fat Gain on Antiretroviral Therapy

BACKGROUND

Fat accumulation and insulin resistance remain a threat to the success of antiretroviral therapy (ART). The role of gut dysfunction in metabolic complications associated with ART initiation is unclear.

METHODS

Human immunodeficiency virus (HIV)-infected ART-naive participants were randomized to tenofovir disoproxil fumarate/emtricitabine plus atazanavir/ritonavir, darunavir/ritonavir, or raltegravir (RAL). Changes in the gut integrity markers zonulin, lipopolysaccharide-binding protein (LBP), and intestinal fatty acid and ileal bile acid binding proteins (I-FABP and I-BABP) were assessed over 96 weeks. Wilcoxon rank-sum tests were used to compare changes between groups and linear regression models to quantify associations between gut markers, insulin resistance, body mass index (BMI), and visceral, subcutaneous, and total adipose tissue (VAT, SAT, and TAT).

RESULTS

: 90% were male and 48% were White non-Hispanic. The median age was 36 years, HIV-1 ribonucleic acid was 4.56 log10 copies/mL, and CD4 count was 338 cells/µL. An overall 1.7-fold increase in I-FABP was observed throughout 96 weeks, with no difference between arms. Zonulin levels increased with RAL compared to protease inhibitor-based regimens (week 96, P = .02); minimal changes in I-BABP or LBP levels were observed. Higher baseline I-FABP levels were associated with increases in VAT, TAT, and BMI (16%, 9%, and 2.5%, respectively; P < .04) over 96 weeks.

CONCLUSIONS

While ART induces changes in the markers of gut barrier dysfunction, the extent to which they improve or worsen the gut barrier function remains unclear. Nevertheless, markers of gut barrier dysfunction in ART-naive individuals predict increases in total and visceral abdominal fat with treatment initiation.

Association Between Immunoglobulin E Levels and Kaposi Sarcoma in African Adults With Human Immunodeficiency Virus Infection

It has been demonstrated that activated mast cells (MCs) are enriched in Kaposi sarcoma (KS) tumors and contribute to the inflammatory microenvironment. Mechanisms driving MC activation, however, are incompletely understood. We sought to understand whether immunoglobulin E (IgE), a potent activator of MCs, was associated with KS incidence and severity. In a cross-sectional study of untreated human immunodeficiency virus (HIV)-infected adults with or without KS in Uganda, we found that patients with KS had higher plasma IgE levels than those without KS. After adjustment for age, sex, CD4+ T-cell count, and HIV RNA levels, there was a dose-response relationship between plasma IgE levels and the presence and severity of KS. Higher eosinophil counts were also associated with IgE levels, and plasma interleukin 33 concentrations were higher in individuals with KS. These findings suggest that IgE-driven atopic inflammation may contribute the pathogenesis of KS. Therapies targeting IgE-mediated MC activation thus might represent a novel approach for treatment or prevention of KS.

Pathogenesis of Aging and Age-related Comorbidities in People with HIV: Highlights from the HIV ACTION Workshop

People with HIV (PWH) experience accentuated biological aging, as defined by markers of inflammation, immune dysfunction, and the epigenetic clock. They also have an elevated risk of multiple age-associated comorbidities. To discuss current knowledge, research gaps, and priorities in aging and age-related comorbidities in treated HIV infection, the NIH program staff organized a workshop held in Bethesda, Maryland in September 2019. This review article describes highlights of discussions led by the Pathogenesis/Basic Science Research working group that focused on three high priority topics: immunopathogenesis; the microbiome/virome; and aging and senescence. We summarize knowledge in these fields and describe key questions for research on the pathogenesis of aging and age-related comorbidities in PWH. Understanding the drivers and mechanisms underlying accentuated biological aging is a high priority that will help identify potential therapeutic targets to improve healthspan in older PWH.

Association Between Chronic Hepatitis C Virus Infection and Myocardial Infarction Among People Living With HIV in the United States

Hepatitis C virus (HCV) infection is common among people living with human immunodeficiency virus (PLWH). Extrahepatic manifestations of HCV, including myocardial infarction (MI), are a topic of active research. MI is classified into types, predominantly atheroembolic type 1 MI (T1MI) and supply-demand mismatch type 2 MI (T2MI). We examined the association between HCV and MI among patients in the Centers for AIDS Research (CFAR) Network of Integrated Clinical Systems, a US multicenter clinical cohort of PLWH. MIs were centrally adjudicated and categorized by type using the Third Universal Definition of Myocardial Infarction. We estimated the association between chronic HCV (RNA+) and time to MI while adjusting for demographic characteristics, cardiovascular risk factors, clinical characteristics, and history of injecting drug use. Among 23,407 PLWH aged ≥18 years, there were 336 T1MIs and 330 T2MIs during a median of 4.7 years of follow-up between 1998 and 2016. HCV was associated with a 46% greater risk of T2MI (adjusted hazard ratio (aHR) = 1.46, 95% confidence interval (CI): 1.09, 1.97) but not T1MI (aHR = 0.87, 95% CI: 0.58, 1.29). In an exploratory cause-specific analysis of T2MI, HCV was associated with a 2-fold greater risk of T2MI attributed to sepsis (aHR = 2.01, 95% CI: 1.25, 3.24). Extrahepatic manifestations of HCV in this high-risk population are an important area for continued research.

Timing of Antiretroviral Therapy and Systemic Inflammation in Sub-Saharan Africa: Results From the META Longitudinal Cohort Study

Chronic inflammation predicts complications in persons with human immunodeficiency virus infection. We compared D-dimer, soluble CD14, and interleukin 6 levels before and 12 months after antiretroviral therapy (ART) initiation, among individuals starting ART during earlier-stage (CD4 T-cell count >350/µL) or late-stage disease (CD4 T-cell count <200/µL). Female sex, older age, viral load, and late-stage disease were associated with pre-ART biomarkers (n = 661; P < .05). However, there were no differences in biomarkers by disease stage after 12 months of ART (n = 438; P > .05), owing to loss from observation and greater declines in biomarkers in late-stage initiators (P < .001). Earlier initiation of ART is associated with decreased inflammation, but levels seem to converge between earlier and later initiators surviving to 12 months.

Presence of asymptomatic cytomegalovirus and Epstein--Barr virus DNA in blood of persons with HIV starting antiretroviral therapy is associated with non-AIDS clinical events

BACKGROUND

Even with antiretroviral therapy (ART), persons with HIV (PWH) experience increased morbidity and mortality. Cytomegalovirus (CMV) and Epstein--Barr virus (EBV) co-infections likely exacerbate inflammatory-related diseases.

OBJECTIVE

To determine if presence of detectable CMV or EBV DNA in peripheral blood mononuclear cells (PBMC) is associated with non-AIDS events among PWH receiving modern ART.

DESIGN

We performed a case--control study of PWH starting ART and HIV-suppressed at year 1 and thereafter, 140 cases who experienced non-AIDS events and 305 matched controls. Events included myocardial infarction, stroke, malignancy, serious bacterial infection or death.

METHODS

Blood samples were studied pre-ART, 1-year post-ART and pre-event. Controls had an event-free follow-up equal or greater than cases. CMV and EBV DNA levels were measured in PBMC. Conditional logistic regression analysis assessed associations and adjusted for relevant covariates; Spearman's correlations compared CMV and EBV DNA levels with other biomarkers.

RESULTS

CMV DNA was detected in PBMC of 25% of participants, EBV DNA was detected in more than 90%. Higher EBV DNA levels were associated with increased risk of events at all time points (odds ratio (OR) per one IQR = 1.5-1.7, all P < 0.009). At year 1, detectable CMV DNA was associated with increased risk of events in most adjusted models (OR = 1.4-1.8, P values ranging 0.03-0.17). Higher levels of CMV and EBV DNA correlated with multiple inflammatory markers and lower CD4/CD8 ratio.

CONCLUSION

In PWH starting ART, detection of CMV and EBV DNA in PBMC was associated with development of non-AIDS events. Clinical trials will be needed to understand causal mechanisms and ways to interrupt them.

The impacts of Ascaridia galli on performance, health, and immune responses of laying hens: new insights into an old problem

Gastrointestinal nematodes are re-emerging in countries where the popularity of free-range poultry production systems is increasing. Amongst all gastrointestinal nematodes, Ascaridia galli is of significant concern due to the parasite's direct life cycle and ability to survive extreme environmental conditions. In laying hens, A. galli parasites have been associated with reduced health, welfare, immunity, and egg production. Direct losses are caused by obstruction and damage of the intestinal tract in hens when high worm burdens are present. These result in reduction in egg production and body weight of infected laying hens, consequently leading to significant economic losses for farmers. Furthermore, heavy infections with A. galli may lead to increased mortality within the flock. Indirect losses are due to suppression of immune system function which can increase susceptibility to secondary infections. Infection with A. galli can also alter nutrient utilization and absorption. Levels of anti- A. galli serum and egg yolk antibodies increase following A. galli infection. Elevated antibodies can be used as an indicator of current or previous infections and therefore can be used as a diagnostic tool. The impact of A. galli on hen health and welfare manifests through the depletion of liver lipid reserves and increased use of energy reserves to mount immune responses against the parasite. This review highlights the variable effects of A. galli infection on the performance, health, egg quality, and emphasizes especially on immune responses of free-range laying hens as well as it evaluates various potential detection methods and preventive and control measures of this parasitic disease.

Anemia risk factors among people living with HIV across the United States in the current treatment era: a clinical cohort study

Background

Anemia is common among people living with HIV infection (PLWH) and is associated with adverse health outcomes. Information on risk factors for anemia incidence in the current antiretroviral therapy (ART) era is lacking.

Methods

Within a prospective clinical cohort of adult PLWH receiving care at eight sites across the United States between 1/2010–3/2018, Cox proportional hazards regression analyses were conducted among a) PLWH free of anemia at baseline and b) PLWH free of severe anemia at baseline to determine associations between time-updated patient characteristics and development of anemia (hemoglobin < 10 g/dL), or severe anemia (hemoglobin < 7.5 g/dL). Linear mixed effects models were used to examine relationships between patient characteristics and hemoglobin levels during follow-up. Hemoglobin levels were ascertained using laboratory data from routine clinical care. Potential risk factors included: age, sex, race/ethnicity, body mass index, smoking status, hazardous alcohol use, illicit drug use, hepatitis C virus (HCV) coinfection, estimated glomerular filtration rate (eGFR), CD4 cell count, viral load, ART use and time in care at CNICS site.

Results

This retrospective cohort study included 15,126 PLWH. During a median follow-up of 6.6 (interquartile range [IQR] 4.3–7.6) years, 1086 participants developed anemia and 465 participants developed severe anemia. Factors that were associated with incident anemia included: older age, female sex, black race, HCV coinfection, lower CD4 cell counts, VL ≥400 copies/ml and lower eGFR.

Conclusion

Because anemia is a treatable condition associated with increased morbidity and mortality among PLWH, hemoglobin levels should be monitored routinely, especially among PLWH who have one or more risk factors for anemia.

Antiretroviral drug class and anaemia risk in the current treatment era among people living with HIV in the USA: a clinical cohort study

OBJECTIVE

Anaemia is common among people living with HIV (PLWH) and has been associated with certain, often older, antiretroviral medications. Information on current antiretroviral therapy (ART) and anaemia is limited. The objective was to compare the associations between anaemia incidence or haemoglobin change with core ART classes in the current ART era.

DESIGN

Retrospective cohort study.

SETTING

USA-based prospective clinical cohort of PLWH aged 18 and above receiving care at eight sites between January 2010 and March 2018.

PARTICIPANTS

16 505 PLWH were included in this study.

MAIN OUTCOME MEASURES

Anaemia risk and haemoglobin change were estimated among PLWH for person-time on a protease inhibitor (PI) or an integrase strand transfer inhibitor (INSTI)-based regimen, relative to a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based reference. We also examined PLWH on regimens containing multiple core classes. Cox proportional hazards regression analyses were conducted to measure the associations between time-updated ART classes and incident anaemia or severe anaemia. Linear mixed effects models were used to examine the relationships between ART classes and haemoglobin change.

RESULTS

During a median of 4.9 years of follow-up, 1040 developed anaemia and 488 developed severe anaemia. Compared with NNRTI use, INSTI-based regimens were associated with an increased risk of anaemia (adjusted HR (aHR) 1.26, 95% CI 1.00 to 1.58) and severe anaemia (aHR 1.51, 95% CI 1.07 to 2.11) and a decrease in haemoglobin level. Time on multiple core classes was also associated with increased anaemia risk (aHR 1.39, 95% CI 1.13 to 1.70), while no associations were found for PI use.

CONCLUSION

These findings suggest INSTI use may increase the risk of anaemia. If confirmed, screening for anaemia development in users of INSTIs may be beneficial. Further research into the underlying mechanisms is warranted.

Super learner analysis of real-time electronically monitored adherence to antiretroviral therapy under constrained optimization and comparison to non-differentiated care approaches for persons living with HIV in rural Uganda

INTRODUCTION

Real-time electronic adherence monitoring (EAM) systems could inform on-going risk assessment for HIV viraemia and be used to personalize viral load testing schedules. We evaluated the potential of real-time EAM (transferred via cellular signal) and standard EAM (downloaded via USB cable) in rural Uganda to inform individually differentiated viral load testing strategies by applying machine learning approaches.

METHODS

We evaluated an observational cohort of persons living with HIV and treated with antiretroviral therapy (ART) who were monitored longitudinally with standard EAM from 2005 to 2011 and real-time EAM from 2011 to 2015. Super learner, an ensemble machine learning method, was used to develop a tool for targeting viral load testing to detect viraemia (>1000 copies/ml) based on clinical (CD4 count, ART regimen), viral load and demographic data, together with EAM-based adherence. Using sample-splitting (cross-validation), we evaluated area under the receiver operating characteristic curve (cvAUC), potential for EAM data to selectively defer viral load tests while minimizing delays in viraemia detection, and performance compared to WHO-recommended testing schedules.

RESULTS

In total, 443 persons (1801 person-years) and 485 persons (930 person-years) contributed to standard and real-time EAM analyses respectively. In the 2011 to 2015 dataset, addition of real-time EAM (cvAUC: 0.88; 95% CI: 0.83, 0.93) significantly improved prediction compared to clinical/demographic data alone (cvAUC: 0.78; 95% CI: 0.72, 0.86; p = 0.03). In the 2005 to 2011 dataset, addition of standard EAM (cvAUC: 0.77; 95% CI: 0.72, 0.81) did not significantly improve prediction compared to clinical/demographic data alone (cvAUC: 0.70; 95% CI: 0.64, 0.76; p = 0.08). A hypothetical testing strategy using real-time EAM to guide deferral of viral load tests would have reduced the number of tests by 32% while detecting 87% of viraemia cases without delay. By comparison, the WHO-recommended testing schedule would have reduced the number of tests by 69%, but resulted in delayed detection of viraemia a mean of 74 days for 84% of individuals with viraemia. Similar rules derived from standard EAM also resulted in potential testing frequency reductions.

CONCLUSIONS

Our machine learning approach demonstrates potential for combining EAM data with other clinical measures to develop a selective testing rule that reduces number of viral load tests ordered, while still identifying those at highest risk for viraemia.

HIV-1-induced cytokines deplete homeostatic innate lymphoid cells and expand TCF7-dependent memory NK cells

Human immunodeficiency virus 1 (HIV-1) infection is associated with heightened inflammation and excess risk of cardiovascular disease, cancer and other complications. These pathologies persist despite antiretroviral therapy. In two independent cohorts, we found that innate lymphoid cells (ILCs) were depleted in the blood and gut of people with HIV-1, even with effective antiretroviral therapy. ILC depletion was associated with neutrophil infiltration of the gut lamina propria, type 1 interferon activation, increased microbial translocation and natural killer (NK) cell skewing towards an inflammatory state, with chromatin structure and phenotype typical of WNT transcription factor TCF7-dependent memory T cells. Cytokines that are elevated during acute HIV-1 infection reproduced the ILC and NK cell abnormalities ex vivo. These results show that inflammatory cytokines associated with HIV-1 infection irreversibly disrupt ILCs. This results in loss of gut epithelial integrity, microbial translocation and memory NK cells with heightened inflammatory potential, and explains the chronic inflammation in people with HIV-1.

Differential decay of intact and defective proviral DNA in HIV-1-infected individuals on suppressive antiretroviral therapy

BACKGROUNDThe relative stabilities of the intact and defective HIV genomes over time during effective antiretroviral therapy (ART) have not been fully characterized.METHODSWe used the intact proviral DNA assay (IPDA) to estimate the rate of change of intact and defective proviruses in HIV-infected adults on ART. We used linear spline models with a knot at seven years and a random intercept and slope up to the knot. We estimated the influence of covariates on rates of change.RESULTSWe studied 81 individuals for a median of 7.3 (IQR 5.9-9.6) years. Intact genomes declined more rapidly from initial suppression through seven years (15.7% per year decline; 95% CI -22.8%, -8.0%) and more slowly after seven years (3.6% per year; 95% CI -8.1%, +1.1%). The estimated half-life of the reservoir was 4.0 years (95% CI 2.7-8.3) until year seven and 18.7 years (95% CI 8.2-infinite) thereafter. There was substantial variability between individuals in the rate of decline until year seven. Intact provirus declined more rapidly than defective provirus (P < 0.001) and showed a faster decline in individuals with higher CD4+ T cell nadirs.CONCLUSIONThe biology of the replication-competent (intact) reservoir differs from that of the replication-incompetent (non-intact) pool of proviruses. The IPDA will likely be informative when investigating the impact of interventions targeting the reservoir.FUNDINGDelaney AIDS Research Enterprise, UCSF/Gladstone Institute of Virology & Immunology CFAR, CFAR Network of Integrated Systems, amfAR Institute for HIV Cure Research, I4C and Beat-HIV Collaboratories, Howard Hughes Medical Institute, Gilead Sciences, Bill and Melinda Gates Foundation.

Heavy Cannabis Use Associated With Reduction in Activated and Inflammatory Immune Cell Frequencies in Antiretroviral Therapy-Treated Human Immunodeficiency Virus-Infected Individuals

Background

Cannabis is a widely used drug in the United States, and the frequency of cannabis use in the human immunodeficiency virus (HIV)-infected population is disproportionately high. Previous human and macaque studies suggest that cannabis may have an impact on plasma viral load; however, the relationship between cannabis use and HIV-associated systemic inflammation and immune activation has not been well defined.

Methods

The impact of cannabis use on peripheral immune cell frequency, activation, and function was assessed in 198 HIV-infected, antiretroviral-treated individuals by flow cytometry. Individuals were categorized into heavy, medium, or occasional cannabis users or noncannabis users based on the amount of the cannabis metabolite 11-nor-carboxy-tetrahydrocannabinol (THC-COOH) detected in plasma by mass spectrometry.

Results

Heavy cannabis users had decreased frequencies of human leukocyte antigen (HLA)-DR+CD38+CD4+ and CD8+ T-cell frequencies, compared to frequencies of these cells in non-cannabis-using individuals. Heavy cannabis users had decreased frequencies of intermediate and nonclassical monocyte subsets, as well as decreased frequencies of interleukin 23- and tumor necrosis factor-α-producing antigen-presenting cells.

Conclusions

While the clinical implications are unclear, our findings suggest that cannabis use is associated with a potentially beneficial reduction in systemic inflammation and immune activation in the context of antiretroviral-treated HIV infection.

Changes in the Fungal Marker β-D-Glucan After Antiretroviral Therapy and Association With Adiposity

BACKGROUND

Bacterial translocation in HIV is associated with inflammation and metabolic complications; few data exist on the role of fungal translocation.

METHODS

A5260s was a substudy of A5257, a prospective open label randomized trial in which treatment-naïve people with HIV (PWH) were randomized to tenofovir-emtricitabine (TDF/FTC) plus atazanavir-ritonavir (ATV/r), darunavir-ritonavir (DRV/r), or raltegravir (RAL) over 96 weeks. Baseline was assessed, and changes in β-D-glucan (BDG) were assessed at weeks 4, 24, and 96. Wilcoxon rank-sum tests were used to compare distribution shifts in the changes from baseline between treatment arms and linear regression models to assess associations between BDG and measures of inflammation, body composition, and insulin resistance.

RESULTS

Two hundred thirty-one participants were randomized; 90% were male, the median age was 36 years, HIV-1 RNA was 4.56 log10c/mL, and CD4 cell count was 338 cells/mm3. There was an overall increase in BDG over 96 weeks (1.57 mean fold-change; 95% confidence interval, 1.39 to 1.77) with no differences between arms. Twofold higher BDG levels at week 96 were associated with increases in trunk fat (8%) and total fat (7%) over 96 weeks (P ≤ .035). At week 4, BDG correlated with I-FABP, a marker of enterocyte damage, and zonulin, a marker of intestinal permeability (r = .19-.20; P < .01).

CONCLUSIONS

In treatment-naïve participants initiating antiretroviral therapy (ART) with TDF/FTC and either RAL or ATV/r, DRV/r, BDG, a marker of fungal translocation, increased similarly in all arms over 96 weeks. This may represent continued intestinal damage during ART and resulting fungal translocation. Higher BDG was associated with larger fat gains on ART.