CMV and transplant-related coronary atherosclerosis: an immunohistochemical, in situ hybridization, and polymerase chain reaction in situ study

Cytomegalovirus infection and cardiovascular outcomes in abdominal organ transplant recipients: A systematic review and meta-analysis

INTRODUCTION

Despite advancements in Cytomegalovirus (CMV) management, its impact on graft function, mortality, and cardiovascular (CV) health of organ transplant recipients (OTR) remains a significant concern. We investigated the association between CMV infection and CV events (CVE) in organ (other than heart) transplant recipients.

METHODS

We conducted a comprehensive literature search in PubMed and EMBASE, including studies that reported on CMV infection or disease and post-transplantation CVE. Studies of heart transplant recipients were excluded.

RESULTS

We screened 3875 abstracts and 12 clinical studies were included in the final analysis, mainly in kidney and liver transplant recipients. A significant association was observed between CMV infection and an increased risk of CVE, with a pooled unadjusted hazard ratio (HR) of 1.99 (95% Confidence Intervals [CI] 1.45-2.73) for CMV infection and 1.59 (95% CI 1.21-2.10) for CMV disease. Pooled adjusted HR were 2.17 (95% CI 1.47-3.20) and 1.77 (95% CI 0.83-3.76), respectively. Heterogeneity was low (I2 = 0%) for CMV infection, suggesting consistent association across studies, and moderate-to-high for CMVdisease (I2 = 50% for unadjusted, 53% for adjusted HR).

DISCUSSION

We found a significant association between CMV infection and CV risk in abdominal OTR, underscoring the importance of proactive CMV surveillance and early treatment. Future research should aim for more standardized methodologies to fully elucidate the relationship between CMV and CV outcomes, potentially informing novel preventive and therapeutic strategies that could benefit the CV health of OTR.

The role of human cytomegalovirus in atherosclerosis: a systematic review

Atherosclerosis is a progressive vascular disease with increasing morbidity and mortality year by year in modern society. Human cytomegalovirus (HCMV) infection is closely associated with the development of atherosclerosis. HCMV infection may accelerate graft atherosclerosis and the development of transplant vasculopathy in organ transplantation. However, our current understanding of HCMV-associated atherosclerosis remains limited and is mainly based on clinical observations. The underlying mechanism of the involvement of HCMV infection in atherogenesis remains unclear. Here, we summarized current knowledge regarding the multiple influences of HCMV on a diverse range of infected cells, including vascular endothelial cells, vascular smooth muscle cells, monocytes, macrophages, and T cells. In addition, we described potential HCMV-induced molecular mechanisms, such as oxidative stress, endoplasmic reticulum stress, autophagy, lipid metabolism, and miRNA regulation, which are involved in the development of HCMV-associated atherogenesis. Gaining an improved understanding of these mechanisms will facilitate the development of novel and effective therapeutic strategies for the treatment of HCMV-related cardiovascular disease.

Resource utilization of cytomegalovirus immune globulin in prevention and treatment of cytomegalovirus infection in pediatric heart transplantation

BACKGROUND

There is debate whether cytomegalovirus immunoglobulin (CMV-Ig) is also needed for CMV prevention in heart transplant recipients in the era of good anti-viral drugs.

METHODS

We conducted a cost-savings quality initiative on CMV-Ig eventually leading to discontinuation of routine use of CMV-Ig for CMV prevention. Subsequently, a retrospective cohort study was conducted, comparing patients in cohort I (CMV-Ig plus anti-viral drugs, 2013-2015) to cohort II (anti-virals alone, 2015-2017). The medication acquisition costs and outcomes of CMV infection were assessed.

RESULTS

There were 39 total patients: 22/39(56%) in cohort I, with mean follow-up of 35.14 ± 17.38 months and 17/39(44%) in cohort II, mean follow-up of 19.12 ± 7.08 months. In cohort I, 5/22(22.7%) patients died from causes unrelated to CMV and 0/17 in cohort II died. There were 5/22(22.7%) patients in cohort I, and 2/17(9%) patients in cohort II that developed CMV infection (P = .508). Freedom from rejection was 81.8% (18/22) in cohort I, and 71% (12/17) in cohort II (P = .46), and 100% for allograft vasculopathy. There was significant reduction in medication acquisition cost following the protocol change of $260 839 or $15 343 per patient.

CONCLUSION

Our study demonstrated an acquisition cost savings with similar clinical outcomes utilizing anti-viral CMV prophylaxis alone vs anti-viral prophylaxis plus CMV-Ig.

[Detection of Antigens of Cardiotropic Viruses in Atherosclerotic Plaques in Patients with Fatal Myocardial Infarction]

AIM

To assess the frequency of detection of cardiotropic virus antigens in coronary artery atherosclerotic plaques in patients with fatal myocardial infarction (MI).

MATERIALS AND METHODS

We examined fragments of coronary plaques of 12 patients with fatal type 1 MI. Immunohistochemistry (IHC) of plaques was performed with the paraffin blocks using antibodies to Herpes simplex virus (HSV)-1, HSV-2, HSV-6, cytomegalovirus (CMV), parvovirus B19, adenovirus, Epstein-Barr virus and enteroviruses.

RESULTS

According to the IHC all patients had virus antigens. The most common virus agents in fragments of coronary plaques were HSV-6 (10 patients) and enteroviruses (5 patients). Antigens of CMV, parvovirus B19, adenovirus, Epstein-Barr virus were not detected in any case.

CONCLUSIONS

In this study viral antigens in coronary artery atherosclerotic plaques were found in all victims of fatal MI. There was no difference in the frequency of detection and type of viral agents between plaques in culprit arteries and uncomplicated atherosclerotic plaques.

Human cytomegalovirus infection and coronary heart disease: a systematic review

Background

Human cytomegalovirus (HCMV) infection is closely associated with coronary heart disease.

Main body of the abstract

In 1987, Adam et al. were the first to report an association between HCMV infection and atherosclerosis (AS), and later, many serum epidemiology and molecular biology studies showed that HCMV-infected endothelial cells play an important role in the development of AS. As patients with HCMV are generally susceptible to coronary heart disease, and with the increasing elderly population, a review of recent studies focusing on the relationships of HCMV infection and coronary heart disease is timely and necessary.

Short conclusion

The role of HCMV infection in the development of AS needs further study, since many remaining issues need to be explored and resolved. For example, whether HCMV promotes the development of coronary AS, and what the independent factors that lead to coronary artery AS by viral infection are. A comprehensive understanding of HCMV infection is needed in order to develop better strategies for preventing AS.

Infections and autoimmunity: role of human cytomegalovirus in autoimmune endothelial cell damage

Molecular mimicry between infectious agents and normal human host cell proteins represents one of the possible mechanisms responsible for autoimmunity. Among infectious agents, human cytomegalovirus (HCMV) is an ideal candidate for involvement in autoimmune disorders because of its lifelong persistence through periods of reactivation and latency and because of the extensive manipulation of innate and adaptive immunity. HCMV has been implicated in the pathogenesis of vascular damage in systemic sclerosis (SSc) and atherosclerosis. Based on our data, which demonstrate a cause-and-effect relationship between HCMV and endothelial cell aggression in SSc and atherosclerosis, we propose that immune responses to particular HCMV proteins may result in autoaggression through a mechanism of molecular mimicry of normally expressed endothelial cell surface molecules.

Impact of viral and bacterial infections in coronary artery disease patients

Atherosclerosis is becoming an alarming disease for the existence of healthy human beings in the 21^st century. There are a growing number of agents, either modernized life style generated, competitive work culture related or infection with some bacterial or viral agents, documented every year. These infectious agents do not have proper diagnostics or detection availability in many poor and developing countries. Hence, as active medical researchers, we summarize some aspects of infectious agents and their related mechanisms in this review which may be beneficial for new beginners in this field and update awareness in the field of cardiovascular biology.

Human cytomegalovirus-IgM seropositivity is not associated with atherogenic alterations of lipid profiles and inflammatory status in ischemic stroke patients: a preliminary study

BACKGROUND

Past exposure to human cytomegalovirus has been suggested to participate in the pathogenetic events associated with atherosclerotic lesion establishment and progression. However, whether ongoing human cytomegalovirus infection is related to plaque instability, and subsequent acute cerebral ischemia, is relatively unknown. The purpose of this study was to evaluate the potential relationships between active human cytomegalovirus infection and ischemic stroke, especially in regard to metabolism and inflammation.

METHODS

Ninety-nine acute ischemic stroke patients, associated with large artery atherosclerosis, were divided into two groups based on the presence or absence of human cytomegalovirus immunoglobulin M (IgM) (human cytomegalovirus-IgM-positive/human cytomegalovirus-IgM-negative = 33:66). Baseline clinical characteristics, inflammatory factors, and biochemical assessments were compared in both groups. Then, all patients and human cytomegalovirus-IgM-positive patients were divided into quartiles according to their high-sensitivity C-reactive protein levels, respectively, and risk factors were compared. Finally, correlations between inflammatory factors (high-sensitivity C-reactive protein and white blood cell count) and other atherosclerosis risk factors in both human cytomegalovirus-IgM-positive and -negative subjects were evaluated.

RESULTS

An association between human cytomegalovirus-IgM seropositivity and atherogenic modification of metabolism and inflammatory status were not found in this study. Both age and white blood cell count increased across quartiles of high-sensitivity C-reactive protein in all subjects (P = 0.001), while age and low-density lipoprotein cholesterol increased across quartiles of high-sensitivity C-reactive protein in the human cytomegalovirus-IgM-positive group (P = 0.02 and 0.007, respectively). Multivariate linear regression analysis showed that high-sensitivity C-reactive protein was associated with age in human cytomegalovirus-IgM-positive group (P = 0.002), while no other factor was associated with white blood cell count in these subjects.

CONCLUSION

Our study provided no evidence for the direct implication of active systemic human cytomegalovirus infection, represented by human cytomegalovirus-IgM positivity, in the pathogenesis of acute ischemic strokes, particularly those involving plaque instability and metabolic disorders.

Pathogens and atherosclerosis: update on the potential contribution of multiple infectious organisms to the pathogenesis of atherosclerosis

It is currently unclear what causes the chronic inflammation within atherosclerotic plaques. One emerging paradigm suggests that infection with bacteria and/or viruses can contribute to the pathogenesis of atherosclerosis either via direct infection of vascular cells or via the indirect effects of cytokines or acute phase proteins induced by infection at non-vascular sites. This paradigm has been supported by multiple epidemiological studies that have established positive associations between the risk of cardiovascular disease morbidity and mortality and markers of infection. It has also been supported by experimental studies showing an acceleration of the development of atherosclerosis following infection of hyperlipidaemic animal models. There are now a large number of different infectious agents that have been linked with an increased risk of cardiovascular disease. These include: Chlamydia pneumoniae, Porphyromonas gingivalis, Helicobacter pylori , influenza A virus, hepatitis C virus, cytomegalovirus, and human immunodeficiency virus. However, there are significant differences in the strength of the data supporting their association with cardiovascular disease pathogenesis. In some cases, the infectious agents are found within the plaques and viable organisms can be isolated suggesting a direct effect. In other cases, the association is entirely based on biomarkers. In the following review, we evaluate the strength of the data for individual or groups of pathogens with regard to atherosclerosis pathogenesis and their potential contribution by direct or indirect mechanisms and discuss whether the established associations are supportive of the infectious disease paradigm. We also discuss the failure of antibiotic trials and the question of persistent infection.

Detection of human cytomegalovirus in atherosclerotic carotid arteries in humans

BACKGROUND/PURPOSE

Atherosclerosis plays an important role in stroke. A microbiological infection has been suggested to be involved in the pathogenesis of atherosclerosis, in particular the human cytomegalovirus (HCMV). The objective of this study was to determine the association between HCMV infection and atherosclerosis of the internal carotid arteries in patients of Chinese Han ethnicity with ischemic stroke.

METHODS

HCMV DNA and antigen were detected in atherosclerotic internal carotid arteries from 35 patients with ischemic stroke and 20 controls from a Chinese Han ethnic population. Immunohistochemistry, in situ hybridization and polymerase chain reaction were used to detect the HCMV immediate early (IE) and late (L) antigen as well as DNA in the vascular walls.

RESULTS

We observed that the proportion of cases that tested positive for HCMV IE but not L antigen and DNA was statistically greater in stroke patients compared with the control population.

CONCLUSION

HCMV IE antigen and DNA were associated with the pathological process of atherosclerosis. The vessel wall might be the infection site of the dormant virus.

Microbial risk factors of cardiovascular and cerebrovascular diseases: potential therapeutical options

Infection and inflammation may have a crucial role in the pathogenesis of atherosclerosis. This hypothesis is supported by an increasing number of reports on the interaction between chronic infection, inflammation, and atherogenesis. Assessment of serological and inflammatory markers of infection may be useful adjuncts in identifying those patients who are at a higher risk of developing vascular events, and in whom more aggressive treatments might be warranted.

Cytomegalovirus-associated cutaneous vasculopathy and scleroderma sans inclusion body change

Viruses have long been held to be of pathogenetic importance in the evolution of autoimmune connective tissue disease. We describe 7 adults who developed cutaneous connective tissue disease stigmata in temporal association with recent cytomegalovirus (CMV) infection but without the classic cytopathic changes of CMV infection. We examined 7 adults with clinical presentations encompassing cutaneous vasculitis in 4 and scleroderma in 3. In all 7 patients, there was either IgM seropositivity for CMV and/or CMV DNA isolation from peripheral blood. Although no CMV inclusions were seen, in situ hybridization studies revealed very focal CMV RNA transcript expression with localization mainly to the endothelium. The patients with vasculitis treated with ganciclovir had improvement or resolution of symptoms, whereas only 1 patient with scleroderma received antiviral therapy, without benefit. Another scleroderma patient responded to infliximab therapy. Abortive/partial CMV reactivation can be associated with a syndrome complex mimicking and/or triggering a primary immune-based cutaneous microvascular injury syndrome. Antiviral therapy appears to be of therapeutic value in those cases associated with active necrotizing vasculitic changes. The role of tumor necrosis factor alpha blockers in scleroderma cases temporally associated with CMV infection requires further evaluation.

The surgical and cytopathology of viral infections: utility of immunohistochemistry, in situ hybridization, and in situ polymerase chain reaction amplification

The diagnosis of viral infections is an important part of the daily work of a surgical and cytopathologist. Some viral infections, such as human papillomavirus infection of the lower genital tract, are seen commonly, whereas others, such as fatal enteroviral infection, cannot be diagnosed on routine histological examination and need to be addressed within the clinical context. In general, viral infections are best categorized for the surgical pathologist as low copy/RNA viruses and high copy/DNA viruses. In the latter, viral DNA enters the nucleus, undergoes rapid proliferation, and causes certain cytopathologic changes characteristic of the infection. Immunohistochemistry and/or in situ hybridization yields an intense signal, reflective of the productive infection. In comparison, RNA viruses typically do not show high copy numbers and, although they can induce characteristic cytopathologic changes such as inclusions, often times they do not. In such cases, immunohistochemistry and/or in situ-based hybridization methods, particularly in situ polymerase chain reaction amplification, may be required for a definitive diagnosis. A combination of routine histopathology, clinical information, and immunohistochemistry/in situ-based nucleic acid detection methodologies will allow the surgical pathologist to correctly diagnose viral infections.

Cytomegalovirus-Associated Pulmonary Septal Capillary Injury Sine Inclusion Body Change

The authors describe four patients with symptomatic lung disease morphologically representing a septal capillary injury syndrome temporally associated with serologic and culture evidence of active cytomegalovirus (CMV) infection but without classic cytopathic changes. The authors conducted a thorough review of clinical data, microscopic examination, and in situ hybridization to detect CMV mRNA encoding immediate early protein. The assay detects transcripts that encode early and immediate early proteins. In two cases additional tissue was available for direct immunofluorescent studies. The disease process in each of the patients was morphologically indistinguishable from the pattern of organ injury associated with autoimmune diseases including a small vessel microvascular injury syndrome involving skin and lung and immune complex- mediated glomerulonephritis. Cytopenias were seen in all cases, most commonly thrombocytopenia. All treated patients demonstrated improvement on combined ganciclovir and low-dose steroid therapy. CMV infection may be of pathogenetic importance in some cases of alveolar hemorrhage, especially when accompanied by peripheral blood cytopenia in otherwise healthy patients and if clinical worsening occurs in the setting of a traditional immunosuppressive regimen typically used to treat vasculitis.

Experimental study on the prevention and treatment of murine cytomegalovirus hepatitis by using allitridin

Allitridin (diallyl trisulfide), a main effective compound of Allium sativum (garlic), was previously shown to inhibit the expression of immediate-early antigens and viral proliferation of human cytomegalovirus (HCMV) in vitro. Here we have examined the prophylactic and therapeutic efficacy of allitridin in a non-lethal murine cytomegalovirus (MCMV) hepatitis in methylprednisolone-immunosuppressed BALB/c mice. Allitridin was administered at 25mg/kg per day (equal to the mean human dose) and 75 mg/kg per day in two regimens: prophylaxis plus therapy beginning at 2 days before infection and lasting for 18 days, and therapy lasting for 14 days initiated at 2 days after infection. Ganciclovir (GCV)-treated, infected, and non-infected mice served as controls. MCMV DNA load in the liver, plasma alanine aminotransferase (ALT) level and Knodell's histological activity index (HAI) score of liver section were evaluated. We found that MCMV DNA load was significantly decreased in all allitridin- and GCV-treated mice, compared with infected controls. Concomitantly, histopathological lesions in the liver and plasma ALT levels were reduced. Statistically, no significant differences were detected between the combined allitridin prophylaxis plus therapeutic and therapeutic groups regardless of dose and the GCV groups. Our results demonstrate the therapeutic efficacy of allitridin in mouse models with MCMV hepatitis.

Interaction of antibodies against cytomegalovirus with heat-shock protein 60 in pathogenesis of atherosclerosis

BACKGROUND

Infections and autoimmunity have been implicated in the pathogenesis of atherosclerosis. Cytomegalovirus has been shown to contribute to the disease. Autoantibodies against human heat-shock protein (HSP) 60 are present in most atherosclerotic patients, and their titre correlates with disease severity, suggesting that anti-HSP60 might be implicated in disease pathogenesis. We postulated that cytomegalovirus infection might induce antibodies able to bind human HSP60 and to cause endothelial-cell damage.

METHODS

We studied 180 patients with coronary-artery disease, raised high sensitivity C-reactive protein concentrations, and presence or absence of traditional risk factors; 90 patients with coronary-artery disease, normal values for high sensitivity C-reactive protein, and no traditional risk factors; and 98 controls. Individual sera were used to define the relevant epitope of HSP60 by ELISA. Affinity purified IgGs were used to identify endothelial cell-surface ligands by western blot and to induce apoptotic cell death.

FINDINGS

We identified an 11 aminoacid sequence of HSP60 that was recognised by most patients with coronary-artery disease. This peptide shares homology with cytomegalovirus-derived proteins UL122 and US28. The same patients' sera recognised UL122-derived and US28-derived peptides. Purified IgGs against HSP60 and the viral peptides bound non-stressed human endothelial cells and induced endothelial-cell apoptosis by interaction with cell-surface molecules.

INTERPRETATION

During cytomegalovirus infection, antibodies against the virus can arise that are able to crossreact with human HSP60 and cause apoptosis of non-stressed endothelial cells, which is judged a primary event in the pathogenesis of atherosclerosis.

[Implication and mode of action of infectious agents in the formation of atheromatous plaques. Infection and atherosclerosis]

Different kinds of infectious agents seem to be implied in the atherosclerotic process. Indeed, some bacteria and viruses have been identified in atherosclerotic lesions: Chlamydia pneumoniae, Helicobacter pylori, Streptococcus sanguis, Porphyromonas gingivalis, herpes simplex viruses type 1 and 2, coxsakievirus B and hepatitis virus A. By their ability to induce antigenic and functional changes in the cells of the vascular wall (endothelial cells, smooth muscle cells, monocytes/macrophages, and fibroblasts) and to stimulate immune response as well as oxidative stress, it is more and more tempting to speculate that infectious agents probably play key roles in the initiation and in the formation of atherosclerotic plaques in certain patients.

Detection of Mycoplasma pneumoniae and Chlamydia pneumoniae in ruptured atherosclerotic plaques

This paper reports what is apparently the first observation of Mycoplasma pneumoniae in association with Chlamydia pneumoniae in thrombosed ruptured atheromas. We performed electron microscopy and in situ hybridization in specimens from three patients who died of acute myocardial infarction. These patients had typical symptoms of acute ischemic syndrome. Mycoplasmas were present mainly in the lipid core of the ruptured thrombosed plaque. Vulnerable atheromas are rich in cholesterol and may favor the growth of mycoplasmas, the only microorganisms that require cholesterol for survival. We suggest that the association of Mycoplasma pneumoniae and Chlamydia pneumoniae may increase the virulence of these microorganisms, favoring proliferation, plaque inflammation and possibly plaque rupture.