The Sordid Affair Between Human Herpesvirus and HIV

Evolving mechanisms and presentations of cardiovascular disease in people with HIV: implications for management

People with HIV (PWH) are at elevated risk for cardiovascular diseases (CVDs), including myocardial infarction, heart failure, and sudden cardiac death, among other CVD manifestations. Chronic immune dysregulation resulting in persistent inflammation is common among PWH, particularly those with sustained viremia and impaired CD4+ T cell recovery. This inflammatory milieu is a major contributor to CVDs among PWH, in concert with common comorbidities (such as dyslipidemia and smoking) and, to a lesser extent, off-target effects of antiretroviral therapy. In this review, we discuss the clinical and mechanistic evidence surrounding heightened CVD risks among PWH, implications for specific CVD manifestations, and practical guidance for management in the setting of evolving data.

γδ T cells mediate robust anti-HIV functions during antiretroviral therapy regardless of immune checkpoint expression

Objectives

Although antiretroviral therapy (ART) efficiently suppresses HIV viral load, immune dysregulation and dysfunction persist in people living with HIV (PLWH). γδ T cells are functionally impaired during untreated HIV infection, but the extent to which they are reconstituted upon ART is currently unclear.

Methods

Utilising a cohort of ART-treated PLWH, we assessed the frequency and phenotype, characterised in vitro functional responses and defined the impact of immune checkpoint marker expression on effector functions of both Vδ1 and Vδ2 T cells. We additionally explore the in vitro expansion of Vδ2 T cells from PLWH on ART and the mechanisms by which such expanded cells may sense and kill HIV-infected targets.

Results

A matured NK cell-like phenotype was observed for Vδ1 T cells among 25 ART-treated individuals (PLWH/ART) studied compared to 17 HIV-uninfected controls, with heightened expression of 2B4, CD160, TIGIT and Tim-3. Despite persistent phenotypic perturbations, Vδ1 T cells from PLWH/ART exhibited strong CD16-mediated activation and degranulation, which were suppressed upon Tim-3 and TIGIT crosslinking. Vδ2 T cell degranulation responses to the phosphoantigen (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate at concentrations up to 2 ng mL-1 were significantly impaired in an immune checkpoint-independent manner among ART-treated participants. Nonetheless, expanded Vδ2 T cells from PLWH/ART retained potent anti-HIV effector functions, with the NKG2D receptor contributing substantially to the elimination of infected cells.

Conclusion

Our findings highlight that although significant perturbations remain within the γδ T cell compartment throughout ART-treated HIV, both subsets retain the capacity for robust anti-HIV effector functions.

Cytomegalovirus Infection Facilitates the Costimulation of CD57+CD28- CD8 T Cells in HIV Infection and Atherosclerosis via the CD2-LFA-3 Axis

CD8 T cells are emerging as important mediators in atherosclerosis and cardiovascular disease (CVD). Immune activation may play a particular role in people with HIV (PWH) who are at an increased risk of CVD, even after controlling for known CVD risk factors. Latent CMV infection is associated with increased CVD risk for both PWH and people without HIV, and human CMV-specific CD4 and CD8 T cells are enriched for an immunosenescent phenotype. We previously showed that CMV coinfection in PWH promotes vascular homing and activation of inflammatory CD4 T cells through the CD2-LFA-3 axis. However, the role of CD2/LFA3 costimulation of CD8 T cells in PWH with CMV has yet to be described. In the present study, we demonstrate that CD2 expression on CX3CR1+CD57+CD28- inflammescent CD8 T cells is increased on cells from CMV-seropositive PWH. In vitro CD2/LFA-3 costimulation enhances TCR-mediated activation of these inflammatory CD8 memory T cells. Finally, we show that LFA-3 is highly expressed in aortas of SIV-infected rhesus macaques and in atherosclerotic plaques of people without HIV. Our findings are consistent with a model in which CMV infection enhances CD2 expression on highly proinflammatory CD8 T cells that can then be stimulated by LFA-3 expressed in the vasculature, even in the absence of CD28 costimulation. This model, in which CMV infection exacerbates toxic cytokine and granzyme production by CD8 T cells within the vasculature, highlights a potential therapeutic target in atherosclerosis development and progression, especially for PWH.

Dementias Among Older Males and Females in the U.S. Medicare System With and Without HIV

BACKGROUND

Despite the growing concern that people with HIV (PWH) will experience a disproportionate burden of dementia as they age, very few studies have examined the sex-specific prevalence of dementia, including Alzheimer disease and related dementias (AD/ADRD) among older PWH versus people without HIV (PWOH) using large national samples.

METHODS

We constructed successive cross-sectional cohorts including all PWH aged 65+ years from U.S. Medicare enrollees and PWOH in a 5% national sample of Medicare data from 2007 to 2019. All AD/ADRD cases were identified by ICD-9-CM/ICD-10-CM diagnosis codes. Prevalence of AD/ADRD was calculated for each calendar year by sex-age strata. Generalized estimating equations were used to assess factors associated with dementia and calculate the adjusted prevalence.

RESULTS

PWH had a higher prevalence of AD/ADRD, which increased over time compared with PWOH, especially among female beneficiaries and with increasing age. For example, among those aged 80+ years, the prevalence increased from 2007 to 2019 (females with HIV: 31.4%-44.1%; females without HIV: 27.4%-29.9%; males with HIV: 26.2%-33.3%; males without HIV: 21.0%-23.5%). After adjustment for demographics and comorbidities, the differences in dementia burden by HIV status remained, especially among older age groups.

CONCLUSIONS

Older Medicare enrollees with HIV had an increased dementia burden over time compared with those without HIV, especially women and older subjects. This underscores the need to develop tailored clinical practice guidelines that facilitate the integration of dementia and comorbidity screening, evaluation, and management into the routine primary care of aging PWH.

Molecular Pathogenesis of Human Immunodeficiency Virus-Associated Disease of Oropharyngeal Mucosal Epithelium

The oropharyngeal mucosal epithelia have a polarized organization, which is critical for maintaining a highly efficient barrier as well as innate immune functions. In human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) disease, the barrier and innate immune functions of the oral mucosa are impaired via a number of mechanisms. The goal of this review was to discuss the molecular mechanisms of HIV/AIDS-associated changes in the oropharyngeal mucosa and their role in promoting HIV transmission and disease pathogenesis, notably the development of opportunistic infections, including human cytomegalovirus, herpes simplex virus, and Epstein-Barr virus. In addition, the significance of adult and newborn/infant oral mucosa in HIV resistance and transmission was analyzed. HIV/AIDS-associated changes in the oropharyngeal mucosal epithelium and their role in promoting human papillomavirus-positive and negative neoplastic malignancy are also discussed.

Elevated Antibody Titers to Epstein-Barr Virus and Cytomegalovirus in Patients with Drug-Induced Lupus

Systemic lupus erythematosus (SLE) is an autoimmune disease, which has been associated with Epstein-Barr virus (EBV) and Cytomegalovirus (CMV) infection. Drug-induced lupus (DIL) is a lupus-like disease caused by the intake of therapeutic drugs, which has been estimated to cause approximately 10-15% of lupus-like cases. Although SLE and DIL share common clinical symptoms, there are some fundamental differences between DIL and SLE onset. Moreover, it remains to be examined whether environmental factors, such as EBV and CMV infections, may contribute to the development of DIL. This study focused on examining the possible association between DIL and EBV and CMV infections, by examining IgG titers to EBV and CMV antigens in serum samples by enzyme-linked immunosorbent assays. Antibody titers to EBV early antigen-diffuse and CMV pp52 were found to be significantly elevated in both SLE and DIL patients compared to healthy controls, although no correlation was found for antibodies to the two virus antigens in the respective disease groups. Moreover, total IgG titers were reduced in SLE and DIL serum samples, which may reflect a general lymphocytopenia, which commonly is associated with SLE. The current findings support that EBV and CMV infections may contribute to the development of DIL and that onset of both diseases are related.

The Frequency and Function of NKG2C+CD57+ Adaptive NK Cells in Cytomagalovirus Co-Infected People Living with HIV Decline with Duration of Antiretroviral Therapy

Human cytomegalovirus (CMV) infection drives the expansion and differentiation of natural killer (NK) cells with adaptive-like features. We investigated whether age and time on antiretroviral therapy (ART) influenced adaptive NK cell frequency and functionality. Flow cytometry was used to evaluate the frequency of adaptive and conventional NK cells in 229 CMV⁺ individuals of whom 170 were people living with HIV (PLWH). The frequency of these NK cell populations producing CD107a, CCL4, IFN-γ or TNF-α was determined following a 6-h antibody dependent (AD) stimulation. Though ART duration and age were correlated, longer time on ART was associated with a reduced frequency of adaptive NK cells. In general, the frequency and functionality of NK cells following AD stimulation did not differ significantly between treated CMV⁺PLWH and CMV⁺HIV^- persons, suggesting that HIV infection, per se, did not compromise AD NK cell function. AD activation of adaptive NK cells from CMV⁺PLWH induced lower frequencies of IFN-γ or TNF-α secreting cells in older persons, when compared with younger persons.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Cytomegalovirus viremia and risk of disease progression and death in HIV-positive patients starting antiretroviral therapy

OBJECTIVE

The aim of this study was to assess the prevalence of cytomegalovirus (CMV) viremia in HIV-positive patients starting antiretroviral therapy (ART) and to evaluate its impact on clinical outcomes.

DESIGN

A retrospective analysis of four clinical trials (INSIGHT FIRST, SMART, START, and ANRS REFLATE TB).

METHODS

Stored plasma samples from participants were used to measure CMV viremia at baseline prior to initiating ART and at visits through 1 year of follow-up after ART initiation. CMV viremia was measured centrally using a quantitative PCR assay. Within FIRST, associations of CMV viremia at baseline and through 8 months of ART were examined with a composite clinical outcome of AIDS, serious non-AIDS events, or death using Cox proportional hazards regression.

RESULTS

Samples from a total of 3176 participants, 1169 from FIRST, 137 from ANRS REFLATE TB, 54 from SMART, and 1816 from START were available with baseline CMV viremia prevalence of 17, 26, 0, and 1%, respectively. Pooled across trials, baseline CMV viremia was associated with low CD4 + T-cell counts and high HIV RNA levels. In FIRST, CMV viremia was detected in only 5% of participants between baseline and month 8. After adjustment for CD4 + T-cell count and HIV RNA levels, hazard ratios for risk of clinical outcomes was 1.15 (0.86-1.54) and 2.58 (1.68-3.98) in FIRST participants with baseline and follow-up CMV viremia, respectively.

CONCLUSION

Baseline CMV viremia in HIV-positive patients starting ART is associated with advanced infection and only persistent CMV viremia after ART initiation is associated with a higher risk of morbidity and mortality.

The unconventional way out-Egress of HCMV through multiviral bodies

Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus and the leading cause of congenital disabilities as well as a significant cause of disease in immunocompromised patients. The envelopment and egress of HCMV particles is an essential step of the viral life cycle as it determines viral spread and potentially tropism. Here we review the current literature on HCMV envelopment and egress with a particular focus on the role of virus-containing multivesicular body-like vesicles for virus egress and spread. We discuss the difficulties of determining the cellular provenance of these structures in light of viral redistribution of cellular marker proteins and provide potential paths to illuminate their genesis. Finally, we discuss how divergent egress pathways could result in virions of different tropisms.

Natural Killer Cells in Antibody Independent and Antibody Dependent HIV Control

Infection with the human immunodeficiency virus (HIV), when left untreated, typically leads to disease progression towards acquired immunodeficiency syndrome. Some people living with HIV (PLWH) control their virus to levels below the limit of detection of standard viral load assays, without treatment. As such, they represent examples of a functional HIV cure. These individuals, called Elite Controllers (ECs), are rare, making up <1% of PLWH. Genome wide association studies mapped genes in the major histocompatibility complex (MHC) class I region as important in HIV control. ECs have potent virus specific CD8⁺ T cell responses often restricted by protective MHC class I antigens. Natural Killer (NK) cells are innate immune cells whose activation state depends on the integration of activating and inhibitory signals arising from cell surface receptors interacting with their ligands on neighboring cells. Inhibitory NK cell receptors also use a subset of MHC class I antigens as ligands. This interaction educates NK cells, priming them to respond to HIV infected cell with reduced MHC class I antigen expression levels. NK cells can also be activated through the crosslinking of the activating NK cell receptor, CD16, which binds the fragment crystallizable portion of immunoglobulin G. This mode of activation confers NK cells with specificity to HIV infected cells when the antigen binding portion of CD16 bound immunoglobulin G recognizes HIV Envelope on infected cells. Here, we review the role of NK cells in antibody independent and antibody dependent HIV control.

TIGIT blockade enhances NK cell activity against autologous HIV-1-infected CD4+ T cells

Objectives

During chronic human immunodeficiency virus (HIV)‐1 infection, inhibitory molecules upregulated on lymphocytes contribute to effector cell dysfunction and immune exhaustion. People living with HIV (PLWH) are at greater risk for age‐related morbidities, an issue magnified by human cytomegalovirus (CMV) coinfection. As CMV infection modifies natural killer (NK) cell properties and NK cells contribute to protection against HIV‐1 infection, we considered the role of T‐cell immunoreceptor with immunoglobulin and intracellular tyrosine inhibitory motif domains (TIGIT) in NK cell‐based HIV‐1 immunotherapy and elimination strategies.

Methods

We measured TIGIT expression on immune cell subsets of 95 PLWH and assessed its impact on NK cell function, including elimination of autologous CD4⁺ T cells infected through reactivation of endogenous HIV‐1.

Results

TIGIT was expressed on CD4⁺ T cells, CD8⁺ T cells and NK cells from PLWH. Although TIGIT levels on T cells correlated with HIV‐1 disease progression, the extent of TIGIT expression on NK cells more closely paralleled adaptation to CMV. TIGIT interacts with its predominant ligand, poliovirus receptor (PVR), to inhibit effector cell functions. Circulating CD4⁺ T cells from PLWH more frequently expressed PVR than HIV‐seronegative controls, and PVR expression was enriched in CD4⁺ T cells replicating HIV‐1 ex vivo. Treatment with anti‐TIGIT monoclonal antibodies increased NK cell HIV‐1‐specific antibody‐dependent cytotoxicity in vitro and ex vivo.

Conclusion

Blocking TIGIT may be an effective strategy to invigorate antibody‐dependent NK cell activity against HIV‐1 activated in cellular reservoirs for cure or treatment strategies.

Human Immunodeficiency Virus (HIV) and Human Cytomegalovirus (HCMV) Coinfection of Infant Tonsil Epithelium May Synergistically Promote both HIV-1 and HCMV Spread and Infection

Mother-to-child transmission (MTCT) of human immunodeficiency virus type 1 (HIV-1) and human cytomegalovirus (HCMV) may occur during pregnancy, labor, or breastfeeding. These viruses from amniotic fluid, cervicovaginal secretions, and breast milk may simultaneously interact with oropharyngeal and tonsil epithelia; however, the molecular mechanism of HIV-1 and HCMV cotransmission through the oral mucosa and its role in MTCT are poorly understood. To study the molecular mechanism of HIV-1 and HCMV MTCT via oral epithelium, we established polarized infant tonsil epithelial cells and polarized-oriented ex vivo tonsil tissue explants. Using these models, we showed that cell-free HIV-1 and its proteins gp120 and tat induce the disruption of tonsil epithelial tight junctions and increase paracellular permeability, which facilitates HCMV spread within the tonsil mucosa. Inhibition of HIV-1 gp120-induced upregulation of mitogen-activated protein kinase (MAPK) and NF-κB signaling in tonsil epithelial cells, reduces HCMV infection, indicating that HIV-1-activated MAPK and NF-κB signaling may play a critical role in HCMV infection of tonsil epithelium. HCMV infection of tonsil epithelial cells also leads to the disruption of tight junctions and increases paracellular permeability, facilitating HIV-1 paracellular spread into tonsil mucosa. HCMV-promoted paracellular spread of HIV-1 increases its accessibility to tonsil CD4 T lymphocytes, macrophages, and dendritic cells. HIV-1-enhanced HCMV paracellular spread and infection of epithelial cells subsequently leads to the spread of HCMV to tonsil macrophages and dendritic cells. Our findings revealed that HIV-1- and HCMV-induced disruption of infant tonsil epithelial tight junctions promotes MTCT of these viruses through tonsil mucosal epithelium, and therapeutic intervention for both HIV-1 and HCMV infection may substantially reduce their MTCT. IMPORTANCE Most HIV-1 and HCMV MTCT occurs in infancy, and the cotransmission of these viruses may occur via infant oropharyngeal and tonsil epithelia, which are the first biological barriers for viral pathogens. We have shown that HIV-1 and HCMV disrupt epithelial junctions, reducing the barrier functions of epithelia and thus allowing paracellular penetration of both viruses via mucosal epithelia. Subsequently, HCMV infects epithelial cells, macrophages, and dendritic cells, and HIV-1 infects CD4⁺ lymphocytes, macrophages, and dendritic cells. Infection of these cells in HCMV- and HIV-1-coinfected tonsil tissues is much higher than that by HCMV or HIV-1 infection alone, promoting their MTCT at its initial stages via infant oropharyngeal and tonsil epithelia.

Ganciclovir therapeutic drug monitoring in transplant recipients

BACKGROUND

The use of (val)ganciclovir is complicated by toxicity, slow response to treatment and acquired resistance.

OBJECTIVES

To evaluate a routine therapeutic drug monitoring (TDM) programme for ganciclovir in a transplant patient population.

METHODS

An observational study was performed in transplant recipients from June 2018 to February 2020. Dose adjustments were advised by the TDM pharmacist as part of clinical care. For prophylaxis, a trough concentration (Cmin) of 1-2 mg/L and an AUC24h of >50 mg·h/L were aimed for. For treatment, a Cmin of 2-4 mg/L and an AUC24h of 80-120 mg·h/L were aimed for.

RESULTS

Ninety-five solid organ and stem cell transplant patients were enrolled. Overall, 450 serum concentrations were measured; with a median of 3 (IQR = 2-6) per patient. The median Cmin and AUC24h in the treatment and prophylaxis groups were 2.0 mg/L and 90 mg·h/L and 0.9 mg/L and 67 mg·h/L, respectively. Significant intra- and inter-patient patient variability was observed. The majority of patients with an estimated glomerular filtration rate of more than 120 mL/min/1.73 m2 and patients on continuous veno-venous haemofiltration showed underexposure. The highest Cmin and AUC24h values were associated with the increase in liver function markers and decline in WBC count as compared with baseline.

CONCLUSIONS

This study revealed that a standard weight and kidney function-based dosing regimen resulted in highly variable ganciclovir Cmin and under- and over-exposure were observed in patients on dialysis and in patients with increased renal function. Clearly there is a need to explore the impact of concentration-guided dose adjustments in a prospective study.

Clinical consequences of asymptomatic cytomegalovirus in treated human immunodeficency virus infection

PURPOSE OF REVIEW

Despite antiretroviral therapy (ART)-mediated viral suppression, people with human immunodeficiency virus (HIV) (PWH) have increased morbidity and mortality. Immune activation and inflammation persist on ART and predict these complications. Over 90% of PWH have cytomegalovirus (CMV) co-infection, and CMV is considered a plausible contributor to this persistent immune activation.

RECENT FINDINGS

A detailed understanding of the link between CMV and multimorbidity is needed, particularly as research moves toward identifying potential targeted therapeutics to attenuate inflammation-mediated morbidity and mortality in treated HIV. We review the literature on the association between CMV and immune activation as well as multiple end-organ complications including cardiovascular disease, venous thromboembolic disease, metabolic complications, gastrointestinal dysfunction, central nervous system involvement, birth sex-related differences, and the relation to the HIV reservoir. We conclude with a discussion of ongoing therapeutic efforts to target CMV.

SUMMARY

As CMV is a plausible driver of multiple comorbidities through persistent immune activation in treated HIV, future research is needed and planned to address its causal role as well as to test novel therapeutics in this setting.

Probing the Interface of HIV and Inflammaging

PURPOSE OF REVIEW

Systemic inflammation increases as a consequence of aging (inflammaging) and contributes to age-related morbidities. Inflammation in people living with HIV is elevated compared with the general population even after prolonged suppression of viremia with anti-retroviral therapy. Mechanisms that contribute to inflammation during aging and in treated HIV disease are potentially interactive, leading to an exaggerated inflammatory phenotype in people with HIV.

RECENT FINDINGS

Recent studies highlight roles for anti-retroviral therapy, co-infections, immune system alterations, and microbiome perturbations as important contributors to HIV-associated inflammation. These factors likely contribute to increased risk of age-related morbidities in people living with HIV. Understanding mechanisms that exaggerate the inflammaging process in people with HIV may lead to improved intervention strategies, ultimately, extending both lifespan and healthspan.

Venous thromboembolism in people living with HIV infection (PWH)

The risk of venous thromboembolism (VTE) and of recurrent VTE remain elevated in people living with HIV compared to controls still with contemporary antiretroviral therapy (ART). The pathophysiology of VTE in HIV is multi factorial and includes an interplay among traditional risk factors, HIV-specific factors, behavioral factors, exposure to ART and other therapies, coinfections, and co-morbidities.

Cytokine Network and Sexual Human Immunodeficiency Virus Transmission in Men Who Have Sex With Men

BACKGROUND

Seminal human immunodeficiency virus (HIV) transmission from men to their partners remains the main driver of HIV epidemics worldwide. Semen is not merely a carrier of the virus, but also provides an immunological milieu that affects HIV transmission.

METHODS

We collected blood and semen from people with HIV whose epidemiologically linked sexual partners either did or did not acquire HIV. Viral transmission was confirmed by phylogenetic linkage (HIV pol). We measured the concentration of 34 cytokines/chemokines by Luminex in the blood and semen of 21 source partners who transmitted HIV (transmitters) and 22 who did not transmit HIV (nontransmitters) to their sexual partners. Differences between cytokine profiles in transmitters versus nontransmitters were analyzed using the multivariate statistical technique of partial least square discriminant analysis.

RESULTS

The cytokine profile in seminal fluid, but not in peripheral blood, was significantly different between men who have sex with men (MSM) who transmitted HIV and those who did not transmit HIV to their sexual partners (E = 19.77; P < .01). This difference persisted after excluding people with undetectable HIV RNA levels in nontransmitters.

CONCLUSIONS

Seminal cytokine profiles correlated with transmission or nontransmission of HIV from the infected MSM to their partners, independently from seminal viral load. Seminal cytokine spectra might be a contributing determinant of sexual HIV transmission, thus providing new directions for the development of strategies aimed at preventing HIV transmission.

Dysfunctional Immunometabolism in HIV Infection: Contributing Factors and Implications for Age-Related Comorbid Diseases

PURPOSE OF REVIEW

An increasing body of evidence indicates that persons living with HIV (PLWH) display dysfunctional immunometabolism. Here, we provide an updated review of this topic and its relationship to HIV-associated immune stimuli and age-related disease.

RECENT FINDINGS

HIV infection alters immunometabolism by increasing reliance on aerobic glycolysis for energy and productive infection and repurposing oxidative phosphorylation machinery for immune cell proliferation and survival. Recent studies in PLWH with diabetes mellitus or cardiovascular disease have identified an association with elevated T cell and monocyte glucose metabolism, respectively. Immunometabolic dysfunction has also been observed in PLWH in frailty and additional studies suggest a role for immunometabolism in non-AIDS defining cancers and neurocognitive disease. There is a plethora of HIV-associated immune stimuli that could drive immunometabolic dysfunction and age-related disease in PLWH, but studies directly examining their relationship are lacking. Immunometabolic dysfunction is characteristic of HIV infection and is a potential link between HIV-associated stimuli and age-related comorbidities.

Novel Strategies to Combat CMV-Related Cardiovascular Disease

Cytomegalovirus (CMV), a ubiquitous human pathogen that is never cleared from the host, has long been thought to be relatively innocuous in immunocompetent adults, but causes severe complications including blindness, end-organ disease, and death in newborns and in immuno-compromised individuals, such as organ transplant recipients and those suffering from AIDS. Yet even in persons with intact immunity, CMV infection is associated with profound stimulation of immune and inflammatory pathways. Carriers of CMV infection also have an elevated risk of developing cardiovascular complications. In this review, we define the proposed mechanisms of how CMV contributes to cardiovascular disease (CVD), describe current approaches to target CMV, and discuss how these strategies may or may not alleviate cardiovascular complications in those with CMV infection. In addition, we discuss the special situation of CMV coinfection in people with HIV infection receiving antiretroviral therapy, and describe how these 2 viral infections may interact to potentiate CVD in this especially vulnerable population.

Subclinical Cytomegalovirus and Epstein-Barr Virus Shedding Is Associated with Increasing HIV DNA Molecular Diversity in Peripheral Blood during Suppressive Antiretroviral Therapy

Cytomegalovirus (CMV) almost universally infects persons with HIV (PWH), and it is a driver of persistent inflammation and HIV persistence. The mechanisms underlying the association between CMV (and possibly other herpesviruses) and HIV persistence are unclear. Serially collected blood samples were obtained from men who have sex with men (MSM) who started antiretroviral therapy (ART) within 1 year of their estimated date of HIV infection (EDI). Total CMV and Epstein-Barr virus (EBV) DNA were quantified in peripheral blood mononuclear cells by droplet digital PCR (ddPCR). Deep sequencing of the HIV DNA partial env gene was performed, and the dynamics of viral diversity over time were analyzed in relation to CMV and EBV shedding status. In total, 37 MSM PWH were included and followed for a median of 23 months (IQR, 22 to 28). Participants started ART within a median of 3.1 months (IQR, 1.5 to 6.5) after EDI and remained virally suppressed thereafter. A total of 18 participants (48.6%) were classified as high EBV shedders, while 19 (51.4%) were classified as CMV shedders. In longitudinal analyses, normalized molecular diversity levels tended to increase over time among participants with detectable CMV and high EBV DNA (0.03 ± 0.02, P = 0.08), while they significantly declined among participants with no/low viral shedding (-0.04 ± 0.02, P = 0.047, interaction P < 0.01). Subclinical CMV and EBV shedding could contribute to the dynamics of the HIV DNA reservoir during suppressive ART. Whether persistent CMV/EBV replication could be targeted as a strategy to reduce the size of the latent HIV reservoir is an avenue that should be explored.IMPORTANCE As part of this study, we evaluated the molecular characteristics of the HIV DNA reservoir over time during antiretroviral treatment (ART) in relation to those of other chronic viral infections (i.e., cytomegalovirus [CMV] and Epstein-Barr virus [EBV]). We demonstrated that the presence of CMV and high-level EBV DNA in peripheral blood cells was associated with changes in HIV DNA molecular diversity. Specifically, HIV DNA molecular diversity increased over time among participants with detectable CMV and high-level EBV DNA, while it significantly declined among participants with no/low viral shedding. Although the current study design does not allow causality to be inferred, it does support the theory that persistent CMV and EBV shedding could contribute to the dynamics of the HIV DNA reservoir during suppressive ART, even when ART is initiated during the earliest phases of HIV infection.

Sex Differences in CMV Replication and HIV Persistence During Suppressive ART

BACKGROUND

The association between subclinical cytomegalovirus (CMV) replication and HIV persistence has not been investigated in cis-gender women with HIV.

METHODS

Fifty virologically suppressed female participants with HIV were prospectively enrolled and provided oral, vaginal, and urine samples and peripheral blood mononuclear cells at 1 cross-sectional time point. CMV DNA was quantified in each specimen by real-time polymerase chain reaction (PCR). Cellular HIV DNA and HIV RNA transcripts (unspliced and multiply spliced [ms] encoding tat-rev) were quantified by droplet digital (dd) PCR in peripheral blood cells. Forty-nine male individuals with HIV and CMV (historical data) were used as controls.

RESULTS

Levels of cellular HIV DNA and unspliced HIV RNA were not different between sexes, but female participants had less detectable msHIV RNA and CMV DNA compared with males (both P < .01). Unlike previously described for males, the presence of CMV DNA was not associated with increased HIV DNA in females. Among female participants, premenopausal status was independently associated with lower HIV DNA compared with postmenopause, after adjusting for nadir CD4 count (P < .01).

CONCLUSIONS

Female participants with HIV had reduced cellular HIV RNA and less subclinical CMV DNA compared with males but overall similar HIV DNA levels in our study. Postmenopausal status was independently associated with higher HIV DNA levels among female participants.

Uracil-Containing Heterodimers of a New Type: Synthesis and Study of Their Anti-Viral Properties

Widespread latent herpes viral infections within a population can lead to the development of co-infections in HIV-infected patients. These infections are not particularly dangerous for healthy individuals and often occur with minimal symptoms, but for those who are immunocompromised, these infections can accelerate the acute phase of HIV infection and AIDS. Thus, the idea of designing compounds that could combine activity against HIV and co-infections would seem promising. In that regard, eleven compounds were synthesized that represent conjugates of non-nucleoside HIV reverse transcriptase inhibitors and nucleoside inhibitors of the herpes family viruses with the hope that these novel heterodimers will result in dual activity against HIV and concomitant herpes virus infections.

Pathogenic microorganism detection in AIDS patients using bronchoalveolar lavage fluid

This study aimed to investigate the use of fiberoptic bronchoscopy and bronchoalveolar lavage in the diagnosis of pulmonary pathogenic microorganism infection in AIDS patients. We retrospectively analyzed the clinical data, fiberoptic bronchoscopy and bronchoalveolar lavage fluid laboratory examinations of 209 AIDS patients with pulmonary infection. Among 209 patients, we found 42 cases of mycobacterial infection, 3 cases of bacterial infection, 58 cases of pneumocystis carinii pneumonia (PCP), 27 cases that were fungal positive, 99 cases of CMV, and 103 cases positive for GM test of which 83 cases were considered Aspergillus positive. BALF pathogen distribution was related to CD4+ T lymphocyte count. The primary pathogens of pulmonary infection in AIDS patients were cytomegalovirus, Mycobacterium tuberculosis, fungi, and Pneumocystis carinii. Fiberoptic bronchoscopy and bronchoalveolar lavage are important in the diagnosis of pathogenic microorganisms in lung infections of AIDS patients.

Cytomegalovirus Coinfection Is Associated with Increased Vascular-Homing CD57+ CD4 T Cells in HIV Infection

Cytotoxic CD4 T cells are linked to cardiovascular morbidities and accumulate in both HIV and CMV infections, both of which are associated with increased risk of cardiovascular disease (CVD). In this study, we identify CMV coinfection as a major driver of the cytotoxic phenotype, characterized by elevated CD57 expression and reduced CD28 expression, in circulating CD4 T cells from people living with HIV infection, and investigate potential mechanisms linking this cell population to CVD. We find that human CD57+ CD4 T cells express high levels of the costimulatory receptor CD2 and that CD2/LFA-3 costimulation results in a more robust and polyfunctional effector response to TCR signals, compared with CD28-mediated costimulation. CD57+ CD4 T cells also express the vascular endothelium-homing receptor CX3CR1 and migrate toward CX3CL1-expressing endothelial cells in vitro. IL-15 promotes the cytotoxic phenotype, elevates CX3CR1 expression, and enhances the trafficking of CD57+ CD4 T cells to endothelium and may therefore be important in linking these cells to cardiovascular complications. Finally, we demonstrate the presence of activated CD57+ CD4 T cells and expression of CX3CL1 and LFA-3 in atherosclerotic plaque tissues from HIV-uninfected donors. Our findings are consistent with a model in which cytotoxic CD4 T cells contribute to CVD in HIV/CMV coinfection and in atherosclerosis via CX3CR1-mediated trafficking and CD2/LFA-3-mediated costimulation. This study identifies several targets for therapeutic interventions and may help bridge the gap in understanding how CMV infection and immunity are linked to increased cardiovascular risk in people living with HIV infection.

Where do we Stand after Decades of Studying Human Cytomegalovirus?

Human cytomegalovirus (HCMV), a linear double-stranded DNA betaherpesvirus belonging to the family of Herpesviridae, is characterized by widespread seroprevalence, ranging between 56% and 94%, strictly dependent on the socioeconomic background of the country being considered. Typically, HCMV causes asymptomatic infection in the immunocompetent population, while in immunocompromised individuals or when transmitted vertically from the mother to the fetus it leads to systemic disease with severe complications and high mortality rate. Following primary infection, HCMV establishes a state of latency primarily in myeloid cells, from which it can be reactivated by various inflammatory stimuli. Several studies have shown that HCMV, despite being a DNA virus, is highly prone to genetic variability that strongly influences its replication and dissemination rates as well as cellular tropism. In this scenario, the few currently available drugs for the treatment of HCMV infections are characterized by high toxicity, poor oral bioavailability, and emerging resistance. Here, we review past and current literature that has greatly advanced our understanding of the biology and genetics of HCMV, stressing the urgent need for innovative and safe anti-HCMV therapies and effective vaccines to treat and prevent HCMV infections, particularly in vulnerable populations.

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.

Subordinate Effect of -21M HLA-B Dimorphism on NK Cell Repertoire Diversity and Function in HIV-1 Infected Individuals of African Origin

Natural Killer (NK) cells play an important role in antiviral defense and their potent effector function identifies them as key candidates for immunotherapeutic interventions in chronic viral infections. Their remarkable functional agility is achieved by virtue of a wide array of germline-encoded inhibitory and activating receptors ensuring a self-tolerant and tunable repertoire. NK cell diversity is generated by a combination of factors including genetic determinants and infections/environmental factors, which together shape the NK cell pool and functional potential. Recently a genetic polymorphism at position -21 of HLA-B, which influences the supply of HLA-E binding peptides and availability of HLA-E for recognition by the inhibitory NK cell receptor NKG2A, was shown to have a marked influence on NK cell functionality in healthy human cytomegalovirus (HCMV) seronegative Caucasian individuals. In this study, -21 methionine (M)-expressing alleles supplying HLA-E binding peptides were largely poor ligands for inhibitory killer immunoglobulin-like receptors (KIRs), and a bias to NKG2A-mediated education of functionally-potent NK cells was observed. Here, we investigated the effect of this polymorphism on the phenotype and functional capacity of peripheral blood NK cells in a cohort of 36 African individuals with human immunodeficiency virus type 1 (HIV-1)/HCMV co-infection. A similarly profound influence of dimorphism at position -21 of HLA-B on NK cells was not evident in these subjects. They predominantly expressed African specific HLA-B and -C alleles that contribute a distinct supply of NKG2A and KIR ligands, and these genetic differences were compounded by the marked effect of HIV-1/HCMV co-infection on NK cell differentiation. Together, these factors resulted in a lack of correlation of the HLA-B -21 polymorphism with surface abundance of HLA-E and loss of the NK cell functional advantage in subjects with -21M HLA-B alleles. Instead, our data suggest that during HIV/HCMV co-infection exposure of NK cells to an environment that displays altered HLA-E ligands drives adaptive NKG2C+ NK cell expansions influencing effector responses. Increased efforts to understand how NK cells are functionally calibrated to self-HLA during chronic viral infections will pave the way to developing targeted therapeutic interventions to overcome the current barriers to enhancing immune-based antiviral control.

Cytomegalovirus and Epstein-Barr Virus Associations with Neurological Diseases and the Need for Vaccine Development

Herpesviruses have been isolated from a wide range of hosts including humans—for which, nine species have been designated. The human herpesviruses are highly host adapted and possess the capacity for latency, allowing them to survive in the host for life, effectively hidden from the immune system. This ability of human herpesviruses to modulate the host immune response poses particular challenges for vaccine development but at the same time proves attractive for the application of human herpesvirus vaccines to certain spheres of medicine. In this review, congenital cytomegalovirus (CMV) infection and hearing loss will be described followed by a comment on the status of current vaccine development. Secondly, the association of Epstein–Barr virus (EBV) infection with multiple sclerosis (MS) and how EBV vaccination may be of benefit will then be discussed. Prevention of congenital CMV by vaccination is an attractive proposition and several vaccines have been evaluated for potential use. Particularly challenging for the development of CMV vaccines are the needs to prevent primary infection, reinfection, and reactivation at the same time as overcoming the capacity of the virus to generate highly sophisticated immunomodulatory mechanisms. Cost and the practicalities of administering potential vaccines are also significant issues, particularly for low- and middle-income countries, where the burden of disease is greatest. An effective EBV vaccine that could prevent the 200,000 new EBV-associated malignancies which occur globally each year is not currently available. There is increasing interest in developing EBV vaccines to prevent MS and, in view of the association of infectious mononucleosis with MS, reducing childhood infectious mononucleosis is a potential intervention. Currently, there is no licensed EBV vaccine and, in order to progress the development of EBV vaccines for preventing MS, a greater understanding of the association of EBV with MS is required.

Extracellular vesicle-mediated intercellular communication in HIV-1 infection and its role in the reservoir maintenance

HIV-1 infection is efficiently controlled by combination anti-retroviral therapy (cART). However, despite preventing disease progression, cART does not eradicate virus infection which persists in a latent form for an individual's lifetime. The latent reservoir comprises memory CD4⁺ T lymphocytes, macrophages, and dendritic cells; however, for the most part, the reservoir is generated by virus entry into activated CD4⁺ T lymphocytes committed to return to a resting state, even though resting CD4⁺ T lymphocytes can be latently infected as well. The HIV-1 reservoir is not recognized by the immune system, is quite stable, and has the potential to re-seed systemic viremia upon cART interruption. Viral rebound can occur even after a long period of cART interruption. This event is most likely a consequence of the extended half-life of the HIV-1 reservoir, the maintenance of which is not clearly understood. Several recent studies have identified extracellular vesicles (EVs) as a driving force contributing to HIV-1 reservoir preservation. In this review, we discuss recent findings in the field of EV/HIV-1 interplay, and then propose a mechanism through which EVs may contribute to HIV-1 persistence despite cART. Understanding the basis of the HIV-1 reservoir maintenance continues to be a matter of great relevance in view of the limitations of current strategies aimed at HIV-1 eradication.

Natural selection favoring more transmissible HIV detected in United States molecular transmission network

HIV molecular epidemiology can identify clusters of individuals with elevated rates of HIV transmission. These variable transmission rates are primarily driven by host risk behavior; however, the effect of viral traits on variable transmission rates is poorly understood. Viral load, the concentration of HIV in blood, is a heritable viral trait that influences HIV infectiousness and disease progression. Here, we reconstruct HIV genetic transmission clusters using data from the United States National HIV Surveillance System and report that viruses in clusters, inferred to be frequently transmitted, have higher viral loads at diagnosis. Further, viral load is higher in people in larger clusters and with increased network connectivity, suggesting that HIV in the United States is experiencing natural selection to be more infectious and virulent. We also observe a concurrent increase in viral load at diagnosis over the last decade. This evolutionary trajectory may be slowed by prevention strategies prioritized toward rapidly growing transmission clusters.

Higher Anti-Cytomegalovirus Immunoglobulin G Concentrations Are Associated With Worse Neurocognitive Performance During Suppressive Antiretroviral Therapy

Background

Cytomegalovirus (CMV) has been linked to higher risk of cardiovascular disease and mortality. We aimed to determine if CMV is associated with neurocognitive performance in adults infected with human immunodeficiency virus (HIV).

Methods

In this cross-sectional analysis, anti-CMV immunoglobulin G (IgG) concentrations in blood and CMV DNA copies in blood and cerebrospinal fluid (CSF) were measured in stored specimens of 80 HIV-infected adults who were previously assessed with a comprehensive neurocognitive test battery. Thirty-eight were taking suppressive antiretroviral therapy (ART) and 42 were not taking ART. A panel of 7 soluble biomarkers was measured by immunoassay in CSF.

Results

Anti-CMV IgG concentrations ranged from 5.2 to 46.1 IU/mL. CMV DNA was detected in 7 (8.8%) plasma specimens but in no CSF specimens. Higher anti-CMV IgG levels were associated with older age (P = .0017), lower nadir CD4+ T-cell count (P < .001), AIDS (P < .001), and higher soluble CD163 (P = .009). Higher anti-CMV IgG levels trended toward an association with worse neurocognitive performance overall (P = .059). This correlation was only present in those taking suppressive ART (P = .0049). Worse neurocognitive performance remained associated with higher anti-CMV IgG levels after accounting for other covariates in multivariate models (model P = .0038). Detectable plasma CMV DNA was associated with AIDS (P = .05) but not with neurocognitive performance.

Conclusions

CMV may influence neurocognitive performance in HIV-infected adults taking suppressive ART. Future clinical trials of anti-CMV therapy should help to determine whether the observed relationships are causal.

A rare case of CMV pneumonia in HIV-infection

Cytomegalovirus (CMV) pneumonia is a rare opportunistic infection in the setting of HIV (Human Immunodeficiency Virus)-infection. Establishing accurate diagnosis of CMV pneumonia in HIV-infection can be challenging. Co-infections by multiple opportunistic pathogens are common and a high degree of clinical vigilance to evaluate for multiple infections, including CMV pneumonia, should be maintained. As there can be a degree of overlap in clinical and radiological features amongst different opportunistic infections affecting the lungs, definitive microbiological and cytohistologic evidences are needed. Reliance on microbiological evidence of CMV in respiratory specimens alone for the diagnosis of CMV pneumonia will lead to an over-diagnosis of the condition and unnecessary treatment.

In our case report, we describe a 53-year-old man with recently diagnosed HIV-infection who presented with non-resolving pneumonia. A diagnosis of CMV pneumonia was reached through consistent clinical, radiological, microbiological and cytologic investigations. The patient made a full clinical recovery after being started on anti-CMV treatment.

The outcome of HIV-positive late presenters according to detectable CMV DNA and anti-CMV treatment

BACKGROUND

HIV late presenters are at high risk of cytomegalovirus (CMV) reactivation and end-organ disease. CMV viraemia has been associated with poor survival but the effect of anti-CMV treatment has not been studied in this setting.

METHODS

HIV-positive patients were included in a retrospective study if presenting with <350 CD4⁺ T-cells/μl and starting an antiretroviral treatment within 3 months of the diagnosis. Primary end point was 5-year survival according to the presence of CMV viraemia, CMV end-organ disease and anti-CMV treatment.

RESULTS

302 patients were included. 157 patients (52%) presented CMV viraemia (CMV-V) and 44 (14.6%) CMV end-organ disease (CMV-EOD). 5-year mortality was higher in CMV-EOD and CMV-V patients than in CMV-negative patients (11.4 versus 9.6 versus 0%; P=0.002). In patients with CMV-V, 5-year mortality was numerically higher in untreated patients (12.9% versus 6.9%; P=0.257) without reaching statistical significance. At univariate analysis the diagnosis of serious opportunistic infections (cryptococcosis, progressive multifocal leukoencephalopathy, lymphoma; P=0.001) and the absence of a negative CMV DNA in the follow-up (P<0.001) were associated with poor outcome. At multivariate analysis HCV coinfection (P=0.016; aOR 6.98, 95% CI 1.50, 32.59), the absence of a negative CMV DNA in the follow-up (P<0.001; aOR 19.40, 95% CI 3.70, 101.64) and marginally the absence of anti-CMV treatment (P=0.052; aOR 4.944, 95% CI 0.99, 24.73) were independent predictors of poor outcome.

CONCLUSIONS

CMV reactivation in HIV-positive patients with poor immunity is associated with worse prognosis: the pre-emptive use of anti-CMV therapy was associated with a better outcome in patients with CMV-V.

Subclinical Cytomegalovirus DNA Is Associated with CD4 T Cell Activation and Impaired CD8 T Cell CD107a Expression in People Living with HIV despite Early Antiretroviral Therapy

Most people living with HIV (PLWH) are coinfected with cytomegalovirus (CMV). Subclinical CMV replication is associated with immune dysfunction and with increased HIV DNA in antiretroviral therapy (ART)-naive and -suppressed PLWH. To identify immunological mechanisms by which CMV could favor HIV persistence, we analyzed 181 peripheral blood mononuclear cell (PBMC) samples from 64 PLWH starting ART during early HIV infection with subsequent virologic suppression up to 58 months. In each sample, we measured levels of CMV and Epstein-Barr virus (EBV) DNA by droplet digital PCR (ddPCR). We also measured expression of immunological markers for activation (HLA-DR+ CD38+), cycling (Ki-67+), degranulation (CD107a+), and the immune checkpoint protein PD-1 on CD4+ and CD8+ T cell memory subsets. Significant differences in percentages of lymphocyte markers by CMV/EBV shedding were identified using generalized linear mixed-effects models. Overall, CMV DNA was detected at 60/181 time points. At the time of ART initiation, the presence of detectable CMV DNA was associated with increased CD4+ T cell activation and CD107a expression and with increased CD8+ T cellular cycling and reduced CD107a expression on CD8+ T cells. While some effects disappeared during ART, greater CD4+ T cell activation and reduced CD107a expression on CD8+ T cells persisted when CMV was present (P < 0.01). In contrast, EBV was not associated with any immunological differences. Among the covariates, peak HIV RNA and CD4/CD8 ratio had the most significant effect on the immune system. In conclusion, our study identified immune differences in PLWH with detectable CMV starting early ART, which may represent an additional hurdle for HIV cure efforts.IMPORTANCE Chronic viral infections such as with HIV and CMV last a lifetime and can continually antagonize the immune system. Both viruses are associated with higher expression of inflammation markers, and recent evidence suggests that CMV may complicate efforts to deplete HIV reservoirs. Our group and others have shown that CMV shedding is associated with a larger HIV reservoir. Subclinical CMV replication could favor HIV persistence via bystander effects on our immune system. In this study, we collected longitudinal PBMC samples from people starting ART and measured immune changes associated with detectable CMV. We found that when CMV was detectable, CD4+ T cell activation was higher and CD8+ T cell degranulation was lower. Both results may contribute to the slower decay of the size of the reservoir during CMV replication, since activated CD4+ T cells are more vulnerable to HIV infection, while the loss of CD8+ T cell degranulation may impede the proper killing of infected cells.

Cardiac Microvascular Dysfunction in Women Living With HIV Is Associated With Cytomegalovirus Immunoglobulin G

Background

People living with HIV (PLWH) appear to be at increased risk of cardiovascular disease (CVD), and this is possibly more pronounced in women living with HIV (WLWH). In the general population, men are more likely to develop obstructive coronary artery disease (CAD), and women often present with a nonobstructive pattern with cardiac microvascular dysfunction. We investigated cardiac microvascular function in men and women living with HIV and tested for association with cytomegalovirus (CMV) immunoglobulin G (IgG), as this has been associated with CVD in PLWH.

Methods

In a cross-sectional study, 94 PLWH on antiretroviral therapy were scanned with ⁸²Rb positron emission tomography/computed tomography at rest and during adenosine-induced stress, which enables the quantification of the myocardial flow reserve (MFR). CMV IgG was measured in plasma.

Results

WLWH had significantly lower MFR compared with men living with HIV (MLWH; P = .003), and >45% of the women had an MFR indicative of cardiac microvascular dysfunction, whereas this was only true for 24% of men (P = .03). CMV IgG concentrations were inversely associated with MFR among WLWH but not MLWH (P = .05 for interaction).

Conclusions

In this first study comparing MFR in women and men living with HIV, we found that WLWH had significantly lower MFR than MLWH and 45% of the women had cardiac microvascular dysfunction despite younger age and lower cardiovascular risk. Furthermore, CMV IgG was inversely associated with MFR among women but not men. This calls for attention to CVD among young WLWH even with low cardiovascular risk.

Coronary artery calcium and intima-media thickness are associated with level of cytomegalovirus immunoglobulin G in HIV-infected patients

Coinfection with cytomegalovirus (CMV) may be involved in cardiovascular disease in HIV-infected patients. We found that higher level of CMV immunoglobulin G (IgG) was independently associated with an increased risk of coronary artery calcium and higher intima-media thickness in HIV-infected patients but not in healthy controls after adjustment for other cardiovascular risk factors and levels of herpes viridae IgG.

Cytomegalovirus and HIV Persistence: Pouring Gas on the Fire

The inherent stability of a small population of T cells that are latently infected with HIV despite antiretroviral therapy (ART) remains a stubborn obstacle to an HIV cure. By exploiting the memory compartment of our immune system, HIV maintains persistence in a small subset of quiescent cells with varying phenotypes, thus evading immune surveillance and clinical detection. Understanding the molecular and immunological mechanisms that maintain the latent reservoir will be critical to the success of HIV eradication strategies. Human cytomegalovirus (CMV), another chronic viral infection, frequently co-occurs with HIV and occupies an oversized proportion of memory T cell responses. CMV and HIV have both evolved complex strategies to manipulate our immune system for their own advantage. Given the increasingly clear links between CMV replication, chronic immune activation, and increased HIV reservoirs, we present a closer examination of the interplay between these two chronic coinfections. Here we review the effects of CMV on the immune system and show how they may affect persistence of the latent HIV reservoir during ART. The studies described herein suggest that hijacking of cytokine and chemokine signaling, manipulation of cell development pathways, and transactivation of HIV expression by CMV might be pouring gas on the fire of HIV persistence. Future interventional studies are required to formally determine the extent to which CMV is causally associated with inflammation and HIV reservoir expansion.

Natural Killer Cells in Human Immunodeficiency Virus-1 Infection: Spotlight on the Impact of Human Cytomegalovirus

Human cytomegalovirus (HCMV) has been closely associated with the human race across evolutionary time. HCMV co-infection is nearly universal in human immunodeficiency virus-1 (HIV-1)-infected individuals and remains an important cofactor in HIV-1 disease progression even in the era of effective antiretroviral treatment. HCMV infection has been shown to have a broad and potent influence on the human immune system and has been linked with the discovery and characterization of adaptive natural killer (NK) cells. Distinct NK-cell subsets, predominately expressing the activating receptor NKG2C and the marker of terminal differentiation CD57, expand in response to HCMV. These NK-cell populations engaged in the long-lasting interaction with HCMV, in addition to characteristic but variable expression of surface receptors, exhibit reduced expression of signaling proteins and transcription factors expressed by canonical NK cells. Broad epigenetic modifications drive the emergence and persistence of HCMV-adapted NK cells that have distinct functional characteristics. NKG2C⁺ NK-cell expansions have been observed in HIV-1 infected patients and other acute and chronic viral infections being systematically associated with HCMV seropositivity. The latter is potentially an important confounding variable in studies focused on the cellular NK-cell receptor repertoire and functional capacity. Here, focusing on HIV-1 infection we review the evidence in favor of “adaptive” changes likely induced by HCMV co-infection in NK-cell subsets. We highlight a number of key questions and how insights into the adaptive behavior of NK cells will inform new strategies exploiting their unique properties in the fight against HIV-1.

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.

Effect of cytomegalovirus and Epstein-Barr virus replication on intestinal mucosal gene expression and microbiome composition of HIV-infected and uninfected individuals

BACKGROUND

HIV-infection is associated with dramatic changes in the intestinal mucosa. The impact of other viral pathogens is unclear.

METHODS

One hundred and eight (108) biopsies from left and right colon (n = 79) and terminal ileum (n = 29) were collected from 19 HIV-infected and 22 HIV-uninfected participants. Levels of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) DNA were measured by droplet digital PCR. Mucosal gene expression was measured via multiplex-assay. Microbiome analysis was performed using bacterial 16S-rDNA-pyrosequencing. The effect of CMV and EBV replication on the microbiome composition and mRNA-expression of selected cytokines (IL-6, IFN-γ, IL-1β, CCL2, IL-8, and IFN-β1) was evaluated.

RESULTS

Overall, CMV and EBV were detected in at least one intestinal site in 60.5 and 78.9% of participants, respectively. HIV-infected individuals demonstrated less detectable CMV (PB = 0.02); CMV was more frequently detected in terminal ileum than colon (PB = 0.05). Detectable EBV was more frequent among HIV-infected (P B= 0.04) without differences by intestinal site. The number of operational taxonomic units did not differ by CMV or EBV detection status. Among HIV-infected participants, higher CMV was only associated with lower relative abundance of Actinobacteria in the ileum (P = 0.03). Presence of CMV was associated with upregulated expression of all selected cytokines in the ileum (all P < 0.02) and higher expression of IL-8 and IFN-β1 in the colon (all P < 0.05) of HIV-uninfected participants, but not among HIV-infected. EBV had no effect on cytokine expression or microbiome composition whatsoever.

CONCLUSION

These results illustrate a complex interplay among HIV-infection, intestinal CMV replication, and mucosal gut environment, and highlight a possible modulatory effect of CMV on the microbial and immune homeostasis.

Preserved immune functionality and high CMV-specific T-cell responses in HIV-infected individuals with poor CD4+ T-cell immune recovery

Poor CD4⁺ T-cell recovery after cART has been associated with skewed T-cell maturation, inflammation and immunosenescence; however, T-cell functionality in those individuals has not been fully characterized. In the present study, we assessed T-cell function by assessing cytokine production after polyclonal, CMV and HIV stimulations of T-cells from ART-suppressed HIV-infected individuals with CD4⁺ T-cell counts >350 cells/μL (immunoconcordants) or <350 cells/μL (immunodiscordants). A group of HIV-uninfected individuals were also included as controls. Since CMV co-infection significantly affected T-cell maturation and polyfunctionality, only CMV⁺ individuals were analyzed. Despite their reduced and skewed CD4⁺ T-cell compartment, immunodiscordant individuals showed preserved polyclonal and HIV-specific responses. However, CMV response in immunodiscordant participants was significantly different from immunoconcordant or HIV-seronegative individuals. In immunodiscordant subjects, the magnitude of IFN-γ⁺ CD8⁺ and IL-2⁺ CD4⁺ T-cells in response to CMV was higher and differently associated with the CD4⁺ T-cell maturation profile., showing an increased frequency of naïve, central memory and EMRA CMV-specific CD4⁺ T-cells. In conclusion, CD4⁺ and CD8⁺ T-cell polyfunctionality was not reduced in immunodiscordant individuals, although heightened CMV-specific immune responses, likely related to subclinical CMV reactivations, may be contributing to the skewed T-cell maturation and the higher risk of clinical progression observed in those individuals.

A common anti-cytomegalovirus drug, ganciclovir, inhibits HIV-1 replication in human tissues ex vivo

BACKGROUND

Cytomegalovirus (CMV) is a common HIV-1 copathogen. Since CMV infection is an important contributor to immune activation, the driving force of HIV disease, an anti-CMV strategy might be beneficial to HIV-infected patients. Shin et al. (J Acquir Immune Defic Syndr 2014; 65:251-258) reported that anti-CMV therapy with valganciclovir in coinfected individuals results in a decrease of HIV viral load that is not accompanied by a decrease of immune activation. This suggests an alternative mechanism for HIV inhibition other than suppression of CMV-mediated inflammation.

METHOD

We evaluated the anti-HIV activity of ganciclovir (GCV), the active form of valganciclovir, on HIV replication in human tissues ex vivo.

RESULTS

We show that GCV has a direct suppressive activity on HIV replication in human tissues ex vivo, including laboratory strains, drug-resistant and primate HIV-1 isolates. We deciphered the mechanism of this inhibition and showed that GCV-TP is incorporated in the nascent DNA chain and acts as a delayed chain terminator.

CONCLUSION

Our results suggest that anti-CMV strategy using valganciclovir in HIV-1-infected individuals may reduce HIV-1 viral load not only indirectly by decreasing CMV-mediated immune activation but also directly by inhibiting HIV-1 reverse transcriptase.

Brief Report: Effect of CMV and HIV Transcription on CD57 and PD-1 T-Cell Expression During Suppressive ART

Supplemental Digital Content is Available in the Text.

HIV-infected men who have sex with men are nearly universally coinfected with cytomegalovirus (CMV). In this study of 45 HIV-infected men who have sex with men virologically suppressed on ART, we found that presence of seminal CMV DNA shedding and higher levels of systemic cellular HIV RNA transcription were both independently associated with increased PD-1 expression on circulating CD4⁺ T cells, but not with higher levels of senescent (CD57⁺) T cells. In addition, greater HIV RNA transcription was associated with lower CD57 expression on CD8 T cells. Although causality cannot be inferred from this retrospective study, these results suggest that asymptomatic CMV replication and residual cellular HIV transcription may contribute to persistent immune dysregulation during suppressive ART.

Cytomegalovirus and HIV: A Dangerous Pas de Deux

Human immunodeficiency virus (HIV)-infected adults who take stable antiretroviral therapy (ART) are at risk for early onset of age-related diseases. This is likely due to a complex interaction between traditional risk factors, HIV infection itself, and other factors, such as underlying immune dysfunction and persistent inflammation. HIV disrupts the balance between the host and coinfecting microbes, worsening control of these potential pathogens. For example, HIV-infected adults are more likely than the general population to have subclinical bursts of cytomegalovirus (CMV) replication at mucosal sites. Production of antigens can activate the immune system and stimulate HIV replication, and it could contribute to the pathogenesis of adverse outcomes of aging, like cardiovascular disease and neurocognitive impairment. Further investigation of the relationships between CMV, immune dysfunction, and unsuccessful aging during chronic HIV infection is warranted.

Elevated cytomegalovirus IgG antibody levels are associated with HIV-1 disease progression and immune activation

OBJECTIVE

To assess the association between cytomegalovirus (CMV) IgG antibody levels, HIV disease progression, and immune activation markers.

DESIGN

A prospective cohort study was conducted among women enrolled in a trial that was designed to determine the effect of acyclovir on HIV disease progression in Rakai, Uganda.

METHODS

The primary endpoints were progression to a CD4 T-cell count less than 250 cells/μl, nontraumatic death, or initiation of antiretroviral therapy (ART). CD4 T-cell counts, HIV viral load, C-reactive protein (CRP), and soluble CD14 levels were assessed biannually for 24 months. CMV IgG antibodies were measured at baseline among all women and annually among a subset of women who initiated ART.

RESULTS

There were 300 HIV/CMV-coinfected participants who contributed a total of 426.4 person-years with a median follow-up time of 1.81 years. Compared with the lowest CMV IgG tertile group at baseline, the highest CMV IgG tertile group was associated with an increased risk to reach a primary endpoint independent of acyclovir use, age, CD4 T-cell count, and HIV viral load at baseline [adjusted hazard ratio = 1.59; (95% CI = 1.05-2.39); P = 0.027]. Among pre-ART visits (n = 1200), women in the highest baseline CMV IgG tertile had increasing annual rates of soluble CD14 and CRP levels, which was not observed for the low CMV IgG tertile group. Compared with pre-ART visits, CMV IgG antibody levels were higher post-ART initiation, and concurrent levels remained associated with soluble CD14 and CRP during suppressive ART (n = 88 person-visits).

CONCLUSION

The magnitude of the immune response to CMV was associated with HIV disease progression and immune activation in sub-Saharan Africa.

Factors Associated with the Size of HIV DNA Reservoir

OBJECTIVE

To review the recent literatures related to the factors associated with the size of the HIV reservoir and their clinical significance.

DATA SOURCES

Literatures related to the size of HIV DNA was collected from PubMed published from 1999 to June 2016.

STUDY SELECTION

All relevant articles on the HIV DNA and reservoir were collected and reviewed, with no limitation of study design.

RESULTS

The composition and development of the HIV-1 DNA reservoir in either treated or untreated patients is determined by integrated mechanism comprising viral characteristics, immune system, and treatment strategies. The HIV DNA reservoir is a combination of latency and activity. The residual viremia from the stochastic activation of the reservoir acts as the fuse, continuing to stimulate the immune system to maintain the activated microenvironment for the rebound of competent virus once treatment with antiretroviral therapy is discontinued.

CONCLUSION

The size of the HIV-1 DNA pool and its composition has great significance in clinical treatment and disease progression.

Longitudinal Viral Dynamics in Semen During Early HIV Infection

Background

Multiple viruses coinfect the male genital tract, influencing each other’s replication and perhaps affecting human immunodeficiency virus (HIV) pathogenesis and disease progression.

Methods

This study included 453 longitudinal seminal samples from 195 HIV-infected men from the San Diego Primary Infection Resource Consortium and 67 seminal samples from HIV-negative healthy controls. Seminal HIV RNA and DNA from 7 human herpesviruses (HHVs) were measured by real-time polymerase chain reaction. Longitudinal shedding rates were determined by Kaplan-Meier survival analysis. Predictors of viral shedding were determined using backwards selection in a multivariable generalized estimating equation model.

Results

HIV-infected participants presented significantly increased rates of seminal HHV shedding compared with HIV-uninfected controls. Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) were the most commonly detected HHV in semen of HIV-infected participants. Persistent shedding was more common for CMV and EBV when compared to other HHVs. With exception of HHV-7, HHV shedding was not significantly influenced by HIV RNA levels, CD4+ cell counts, or antiretroviral therapy. Presence of CMV, EBV, and herpes simplex virus (HSV) were independent predictors of genital HIV RNA shedding after adjusting for plasma HIV RNA and longitudinal measurements.

Conclusions

Seminal replication of multiple HHVs is common in our HIV primary infection cohort. Genital replication of CMV and EBV was the most common and was significantly associated with seminal HIV RNA shedding. Prevalence of HSV shedding was lower and mostly intermittent, but its association with seminal HIV RNA was the strongest. Understanding the complex viral milieu in semen is important for HIV transmission but might also play a role in HIV pathogenesis and disease progression.