High prevalence of human cytomegalovirus in carotid atherosclerotic plaques obtained from Russian patients undergoing carotid endarterectomy

Human cytomegalovirus and neonatal infection

Human cytomegalovirus is an ancient virus that has co-evolved with humans. It establishes a life-long infection in suspectable individuals for which there is no vaccination or cure. The virus can be transmitted to a developing fetus in seropositive pregnant women, and it is the leading cause of congenital infectious disease. While the majority of infected infants remain asymptomatic at birth, congenital cytomegalovirus infection can lead to substantial long-term neurodevelopmental impairments in survivors, resulting in considerable economic and social hardships. Recent discoveries regarding cytomegalovirus pathophysiology and viral replication cycles might enable the development of innovative diagnostics and therapeutics, including an effective vaccine. This Review will detail our understanding of human cytomegalovirus infection, with an in-depth discussion regarding the viral genome and transcriptome that contributes to its pathophysiology. The neonate's clinical course will also be highlighted, including maternal and neonatal testing, treatment recommendations, and long-term outcomes.

Increased frequency of HLA-A*02 in patients with atherosclerosis is associated with VZV seropositivity

BACKGROUND

HLA molecules are inherited key molecules in the immune inflammation and specific responses to environmental pathogens. We investigated the association of HLA-A alleles with Varicella zoster virus (VZV) seropositivity in patients with atherosclerosis (AS).

MATERIALS AND METHODS

Plasma Anti-VZV IgG and molecular HLA type were detected in 203 (100 AS⁺ and 103 AS^-) individuals.

RESULTS

Of 100 AS⁺ individuals, 66 were anti-VZV⁺ and 34 were anti-VZV^-. Of 103 age/sex-matched AS^- individuals, 59 were anti-VZV⁺ and 44 were anti-VZV^-. Anti-VZV-IgG in AS⁺ cases was higher than AS^- controls (p = .034). The mean anti-VZV IgG in HLA-A*02⁺AS⁺ individuals was higher than HLA-A*02⁺AS^- controls (p < .001). HLA-A*02 was associated with VZV-seropositivity (p = .01) in AS⁺ patients. A higher frequency of HLA-A*02-allele in AS⁺ patients compared to AS^- controls (p = .015) and an accumulation of HLA-A*02-allele in AS⁺ anti-VZV⁺ group (33.3%, p = .004) was observed.

CONCLUSIONS

HLA-A alleles and immune responses to VZV are associated with clinical atherosclerosis.

Latent Cytomegalovirus-Driven Recruitment of Activated CD4+ T Cells Promotes Virus Reactivation

Human cytomegalovirus (HCMV) infection is not cleared by the initial immune response but persists for the lifetime of the host, in part due to its ability to establish a latent infection in cells of the myeloid lineage. HCMV has been shown to manipulate the secretion of cellular proteins during both lytic and latent infection; with changes caused by latent infection mainly investigated in CD34+ progenitor cells. Whilst CD34+ cells are generally bone marrow resident, their derivative CD14+ monocytes migrate to the periphery where they briefly circulate until extravasation into tissue sites. We have analyzed the effect of HCMV latent infection on the secretome of CD14+ monocytes, identifying an upregulation of both CCL8 and CXCL10 chemokines in the CD14+ latency-associated secretome. Unlike CD34+ cells, the CD14+ latency-associated secretome did not induce migration of resting immune cell subsets but did induce migration of activated NK and T cells expressing CXCR3 in a CXCL10 dependent manner. As reported in CD34+ latent infection, the CD14+ latency-associated secretome also suppressed the anti-viral activity of stimulated CD4+ T cells. Surprisingly, however, co-culture of activated autologous CD4+ T cells with latently infected monocytes resulted in reactivation of HCMV at levels comparable to those observed using M-CSF and IL-1β cytokines. We propose that these events represent a potential strategy to enable HCMV reactivation and local dissemination of the virus at peripheral tissue sites.

Adaptive Immune Responses in Human Atherosclerosis

Atherosclerosis is a chronic inflammatory disease that is initiated by the deposition and accumulation of low-density lipoproteins in the artery wall. In this review, we will discuss the role of T- and B-cells in human plaques at different stages of atherosclerosis and the utility of profiling circulating immune cells to monitor atherosclerosis progression. Evidence supports a proatherogenic role for intraplaque T helper type 1 (Th1) cells, CD4⁺CD28^null T-cells, and natural killer T-cells, whereas Th2 cells and regulatory T-cells (Treg) have an atheroprotective role. Several studies indicate that intraplaque T-cells are activated upon recognition of endogenous antigens including heat shock protein 60 and oxidized low-density lipoprotein, but antigens derived from pathogens can also trigger T-cell proliferation and cytokine production. Future studies are needed to assess whether circulating cellular biomarkers can improve identification of vulnerable lesions so that effective intervention can be implemented before clinical manifestations are apparent.

Limited effect of duration of CMV infection on adaptive immunity and frailty: insights from a 27-year-long longitudinal study

Objectives

Cytomegalovirus infection is thought to affect the immune system and to impact general health during ageing. Higher CMV‐specific antibody levels in the elderly are generally assumed to reflect experienced viral reactivation during life. Furthermore, high levels of terminally differentiated and CMV‐specific T cells are hallmarks of CMV infection, which are thought to expand over time, a process also referred to as memory inflation.

Methods

We studied CMV‐specific antibody levels over ~ 27 years in 268 individuals (aged 60–89 years at study endpoint), and to link duration of CMV infection to T‐cell numbers, CMV‐specific T‐cell functions, frailty and cardiovascular disease at study endpoint.

Results

In our study, 136/268 individuals were long‐term CMV seropositive and 19 seroconverted during follow‐up (seroconversion rate: 0.56%/year). CMV‐specific antibody levels increased slightly over time. However, we did not find an association between duration of CMV infection and CMV‐specific antibody levels at study endpoint. No clear association between duration of CMV infection and the size and function of the memory T‐cell pool was observed. Elevated CMV‐specific antibody levels were associated with the prevalence of cardiovascular disease but not with frailty. Age at CMV seroconversion was positively associated with CMV‐specific antibody levels, memory CD4⁺ T‐cell numbers and frailty.

Conclusion

Cytomegalovirus‐specific memory T cells develop shortly after CMV seroconversion but do not seem to further increase over time. Age‐related effects other than duration of CMV infection seem to contribute to CMV‐induced changes in the immune system. Although CMV‐specific immunity is not evidently linked to frailty, it tends to associate with higher prevalence of cardiovascular disease.

Human Cytomegalovirus Infections Are Associated With Elevated Biomarkers of Vascular Injury

Background: Human cytomegalovirus (HCMV) infects ~50% of adults in the United States. HCMV infections may cause vascular inflammation leading to cardiovascular disease, but the existing evidence is inconsistent.

Objective: We investigated demographic predictors of HCMV infection and explored associations between HCMV infection status, the intensity of anti-HCMV Immunoglobulin G (IgG) antibody response, and biomarkers of inflammation and endothelial function which are known predictors of cardiovascular disease.

Methods: We conducted a cross-sectional study of 694 adults residing in the Raleigh-Durham-Chapel Hill, NC metropolitan area. Serum samples were tested for IgG antibody response to HCMV, and for biomarkers of vascular injury including soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), C-reactive protein (CRP), and serum amyloid A (SAA). Associations between HCMV and biomarker levels were analyzed using two approaches with HCMV serostatus modeled as a binary variable and as an ordinal variable with five categories comprised of seronegative individuals and quartiles of anti-HCMV antibody responses in seropositive individuals.

Results: HCMV seroprevalence in the study population was 56%. Increased body mass index, increased age, female gender, racial/ethnic minority status, and current smoking were significantly associated with HCMV seropositivity in a multivariate regression analysis. HCMV seropositivity was also associated with 9% (95% confidence interval 4–15%) and 20% (0.3–44%) increases in median levels of sICAM-1 and CRP, respectively, after adjusting for covariates. The association between HCMV seropositivity and median levels of sVCAM-1 and SAA were positive but not statistically significant. Significant positive associations were observed between the intensity of anti-HCMV IgG responses and levels of sICAM-1 and sVCAM-1 (p-values 0.0008 and 0.04 for linear trend, respectively). To our knowledge, this is the first epidemiological study to show a relationship between anti-HCMV IgG responses and vascular injury biomarkers sICAM-1 and sVCAM-1 in the general population.

Conclusion: HCMV infections are associated with vascular injury and inflammation biomarkers in adult residents of North Carolina.

Human cytomegalovirus infection is correlated with atherosclerotic plaque vulnerability in carotid artery

BACKGROUND

Several studies have suggested that human cytomegalovirus (CMV) infection is closely related to the pathogenesis of atherosclerosis. The present study aimed to investigate the association between human CMV infection and carotid atherosclerotic plaque vulnerability in a Chinese population.

METHODS

In total, 42 patients with carotid atherosclerosis (observation group) and 30 healthy volunteers (control group) were recruited in our study from October 2016 to January 2018. Statistical analysis was carried out to calculate the infection rate of CMV in subjects. Spearman's rank analysis was performed to evaluate the correlation between CMV infection and atherosclerotic plaque vulnerability.

RESULTS

The positive rate of CMV was significantly higher in the observation group compared to the control group, and matrix metalloproteinase 9 (MMP-9), tumor necrosis factor-α (TNF-α) and lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) expression levels were also elevated in the observation group compared to those in the control group. In carotid atherosclerotic patients, the detection rate of unstable plaques and the Crouse scores in vulnerable plaque were significantly higher in the CMV-positive group compared to those in the CMV-negative group. As revealed by correlation analysis, CMV infection was significantly positively correlated with plaque vulnerability and expression levels of MMP-9, TNF-α and LOX-1 in carotid atherosclerotic patients.

CONCLUSIONS

Human CMV infection might be a potential risk factor for increased plaque vulnerability in patients with carotid atherosclerosis.

Alterations in Enteric Virome Are Associated With Colorectal Cancer and Survival Outcomes

BACKGROUND & AIMS

Patients with colorectal cancer (CRC) have a different gut microbiome signature than individuals without CRC. Little is known about the viral component of CRC-associated microbiome. We aimed to identify and validate viral taxonomic markers of CRC that might be used in detection of the disease or predicting outcome.

METHODS

We performed shotgun metagenomic analyses of viromes of fecal samples from 74 patients with CRC (cases) and 92 individuals without CRC (controls) in Hong Kong (discovery cohort). Viral sequences were classified by taxonomic alignment against an integrated microbial reference genome database. Viral markers associated with CRC were validated using fecal samples from 3 separate cohorts: 111 patients with CRC and 112 controls in Hong Kong, 46 patients with CRC and 63 controls in Austria, and 91 patients with CRC and 66 controls in France and Germany. Using abundance profiles of CRC-associated virome genera, we constructed random survival forest models to identify those associated with patient survival times.

RESULTS

The diversity of the gut bacteriophage community was significantly increased in patients with CRC compared with controls. Twenty-two viral taxa discriminated cases from controls with an area under the receiver operating characteristic curve of 0.802 in the discovery cohort. The viral markers were validated in 3 cohorts, with area under the receiver operating characteristic curves of 0.763, 0.736, and 0.715, respectively. Clinical subgroup analysis showed that dysbiosis of the gut virome was associated with early- and late-stage CRC. A combination of 4 taxonomic markers associated with reduced survival of patients with CRC (log-rank test, P = 8.1 × 10^-6) independently of tumor stage, lymph node metastases, or clinical parameters. We found altered interactions between bacteriophages and oral bacterial commensals in fecal samples from patients with CRC compared with controls.

CONCLUSIONS

In a metagenomic analysis of fecal samples from patients and controls, we identified virome signatures associated with CRC. These data might be used to develop tools to identify individuals with CRC or predict outcomes.

Using NMR in saliva to identify possible biomarkers of glioblastoma and chronic periodontitis

Nowadays there is increasing interest in identifying–and using–metabolites that can be employed as biomarkers for diagnosing, treating and monitoring diseases. Saliva and NMR have been widely used for this purpose as they are fast and inexpensive methods. This case-control study aimed to find biomarkers that could be related to glioblastoma (GBL) and periodontal disease (PD) and studied a possible association between GBL and periodontal status. The participants numbered 130, of whom 10 were diagnosed with GBL and were assigned to the cases group, while the remaining 120 did not present any pathology and were assigned to the control group. On one hand, significantly increased (p < 0.05) metabolites were found in GBL group: leucine, valine, isoleucine, propionate, alanine, acetate, ethanolamine and sucrose. Moreover, a good tendency to separation between the two groups was observed on the scatterplot of the NMR. On the other hand, the distribution of the groups attending to the periodontal status was very similar and we didn´t find any association between GBL and periodontal status (Chi-Square 0.1968, p = 0.91). Subsequently, the sample as a whole (130 individuals) was divided into three groups by periodontal status in order to identify biomarkers for PD. Group 1 was composed of periodontally healthy individuals, group 2 had gingivitis or early periodontitis and group 3 had moderate to advanced periodontitis. On comparing periodontal status, a significant increase (p < 0.05) in certain metabolites was observed. These findings along with previous reports suggest that these could be used as biomarkers of a PD: caproate, isocaproate+butyrate, isovalerate, isopropanol+methanol, 4 aminobutyrate, choline, sucrose, sucrose-glucose-lysine, lactate-proline, lactate and proline. The scatter plot showed a good tendency to wards separation between group 1 and 3.

How does cytomegalovirus factor into diseases of aging and vaccine responses, and by what mechanisms?

Cytomegalovirus (CMV) is an important pathogen for both clinical and population settings. There is a growing body of research implicating CMV in multiple health outcomes across the life course. At the same time, there is mounting evidence that individuals living in poverty are more likely to be exposed to CMV and more likely to experience many of the chronic conditions for which CMV has been implicated. Further research on the causal role of CMV for health and well-being is needed. However, the strong evidence implicating CMV in type 2 diabetes, autoimmunity, cancer, cardiovascular disease, vaccination, and age-related alterations in immune function warrants clinical and public health action. This imperative is even higher among individuals living in socioeconomically disadvantaged settings and those exposed to high levels of chronic psychosocial stress.

High anti-human cytomegalovirus antibody levels are associated with the progression of essential hypertension and target organ damage in Han Chinese population

Human cytomegalovirus (CMV) infection is associated with hypertension and has been linked with the pathogenesis of increased arterial blood pressure (BP). Currently, whether CMV infection is associated with the progression of hypertension and hypertensive target organ damage (TOD) remains to be identified. We aimed to examine the relationship between CMV infection and the progression of hypertension and hypertensive TOD, which could provide clues on the possible mediating mechanisms, in the Han Chinese population. A total of 372 patients with hypertension and 191 healthy controls (Han participants from Xinjiang, China) were included in the study. Enzyme-linked immunosorbent assay (ELISA) and qPCR were used to detect CMV infection. C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) titers were also analyzed using an ELISA kit. Moreover, cardiovascular disease markers were evaluated by echocardiography, carotid ultrasonography, and tomographic scans. Essential hypertension (EH) patients exhibited a marked increase in CMV IgG antibody, CRP, TNF-α, and IL-6 levels. Higher grade of hypertension and hypertensive TOD had higher CMV IgG antibody and CRP levels. The CMV IgG antibody titers were positively correlated with arterial BP, greater grade of hypertension and hypertensive TOD, and CRP and IL-6 levels. The higher quartile of CMV IgG titer and CRP level were associated with the incidence of hypertension and the progression of hypertension and hypertensive TOD. In the Han Chinese population, high CMV IgG titers are associated with the progression of hypertension and hypertensive TOD. CMV IgG titer >4.25 U could be an independent predictor of hypertension and progression of hypertension, while that >4.85 U could be an independent risk factor for hypertensive TOD. The underlying mechanism may be largely mediated by chronic inflammation.

Human Cytomegalovirus Up-Regulates Endothelin Receptor Type B: Implication for Vasculopathies?

Background. Both endothelin receptor type B ([ET_BR], a G protein-coupled receptor that mediates the vascular effects of the potent vasoconstrictor endothelin-1) and human cytomegalovirus ([HCMV], a ubiquitous herpesvirus) have been implicated in the pathogenesis of cardiovascular disease (CVD). The effects of HCMV infection on ET_BR expression are unknown. We hypothesized that HCMV may contribute to the pathogenesis of CVD via ET_BR modulation.

Methods. Human CMV effects on ET_BR were studied in vitro in endothelial cells (ECs) and smooth muscle cells (SMCs) and ex vivo in human carotid plaque tissue specimens. Expression of ET_BR and viral immediate-early were quantified using quantitative polymerase chain reaction. Functional consequences after ET_BR blockade in ECs were examined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide proliferation, wound healing, tube formation, and flow adhesion assays.

Results. Human CMV is capable of upregulating both ET_BR mRNA and protein expression in ECs and SMCs. The ET_BR was also abundantly expressed in ECs, foam cells, and SMCs, and, more importantly, in HCMV-positive cells in human carotid plaques. Endothelin receptor type B blockade led to decreased proliferation and reduced tumor necrosis factor α-mediated leukocyte recruitment in both uninfected and HCMV-infected ECs. Direct HCMV infection was antimigratory and antiangiogenic in ECs.

Conclusions. Human CMV may contribute to CVD via ET_BR induction.

Macrophage Heterogeneity and Plasticity: Impact of Macrophage Biomarkers on Atherosclerosis

Cardiovascular disease (CVD) is a global epidemic, currently representing the worldwide leading cause of morbidity and mortality. Atherosclerosis is the fundamental pathophysiologic component of CVD, where the immune system plays an essential role. Monocytes and macrophages are key mediators in this aspect: due to their heterogeneity and plasticity, these cells may act as either pro- or anti-inflammatory mediators. Indeed, monocytes may develop heterogeneous functional phenotypes depending on the predominating pro- or anti-inflammatory microenvironment within the lesion, resulting in classic, intermediate, and non-classic monocytes, each with strikingly differing features. Similarly, macrophages may also adopt heterogeneous profiles being mainly M1 and M2, the former showing a proinflammatory profile while the latter demonstrates anti-inflammatory traits; they are further subdivided in several subtypes with more specialized functions. Furthermore, macrophages may display plasticity by dynamically shifting between phenotypes in response to specific signals. Each of these distinct cell profiles is associated with diverse biomarkers which may be exploited for therapeutic intervention, including IL-10, IL-13, PPAR-γ, LXR, NLRP3 inflammasomes, and microRNAs. Direct modulation of the molecular pathways concerning these potential macrophage-related targets represents a promising field for new therapeutic alternatives in atherosclerosis and CVD.

Detection of circulating hcmv-miR-UL112-3p in patients with glioblastoma, rheumatoid arthritis, diabetes mellitus and healthy controls

Background

microRNAs (miRNA) are 18–22 nucleotides long non-coding RNAs that regulate gene expression at a post-transcriptional level. Human cytomegalovirus (HCMV) encodes at least 26 known mature miRNAs. hcmv-miR-UL112-3p (miR-UL112-3p) is the most well characterized HCMV miRNA, which is suggested to play role in establishment and maintenance of viral latency. Elevated miR-UL112-3p levels have been reported to be present in plasma of patients with hypertension.

Objectives

In this study, we aimed to quantify miR-UL112-3p levels in the plasma/serum of patients with Diabetes Mellitus (DM; from the DIGAMI-2 cohort), Glioblastoma multiforme (GBM), Rheumatoid Arthritis (RA) and Healthy Controls (HC).

Study Design

Total RNA was isolated from plasma/serum samples of 87 patients and controls, a TaqMan miRNA assay was performed to detect miR-UL112-3p and the copy numbers were normalized to 10 ng of total RNA. HCMV IgG and IgM were analysed using ELISA.

Results

HCMV miR-UL112-3p was detected in 14/27 (52%) of DM, 5/20 (25%) of GBM, 1/20 (5%) of RA patients and in 2/20 (10%) of HC, respectively. Anti-HCMV IgG was detected in 85%, 65%, 75% of patients and 70% of HC, respectively. Anti-HCMV IgM was found only in one GBM patient of 87 examined patients and controls.

Conclusions

A higher prevalence of miR-UL112-3p was detected in DM and GBM patients than in RA patients and HC. Elevated levels of miR-UL112-3p and higher prevalence of HCMV IgG were observed in DM patients. Whether the presence of circulating miR-UL112-3p denotes a biomarker of HCMV latency or active replication in patients warrants further investigation.

Human cytomegalovirus induces upregulation of arginase II: possible implications for vasculopathies

Both human cytomegalovirus (HCMV) and arginase II (ARG II) have been implicated in the pathogenesis of cardiovascular diseases. The effects of HCMV on ARG II are unknown. The aim of this study was to investigate the effects of HCMV on ARG II expression in endothelial and vascular smooth muscle cells (SMC) both in vitro and ex vivo. Endothelial and SMC were infected with either HCMV or UV-irradiated HCMV. Expression of ARG II, endothelial or inducible nitric oxide synthase (eNOS and iNOS, respectively) and viral immediate early (IE) was quantified using quantitative PCR. Ganciclovir and short interfering RNA were used to determine the viral gene mediating the effects on ARG II. Detection of viral antigens and ARG II expression was performed by immunofluorescence or immunohistochemistry. HCMV infection increased both ARG II mRNA and protein levels in the examined cells; this effect was mediated by the HCMV IE2-p86 protein. The upregulation of ARG II was accompanied by a downregulation of eNOS but an induction of iNOS in HCMV-infected endothelial cells. Both eNOS and iNOS expressions were induced in HCMV-infected SMC. ARG II was abundantly expressed in endothelial cells, foam cells and SMC and was importantly significantly upregulated in HCMV-immunoreactive human carotid atherosclerotic plaques. HCMV IE2-p86 mediates ARG II upregulation in vitro and ARG II is co-expressed with HCMV antigens in human carotid atherosclerotic plaques. We speculate that HCMV may contribute to endothelial dysfunction via ARG II induction and reduced eNOS production.