Cytomegalovirus Research Articles

CD4+ but not CD8+ T cells are required for protection against severe guinea pig cytomegalovirus infections.

Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus and the leading cause of infectious disease related birth defects worldwide. How the immune response modulates the risk of intrauterine transmission of HCMV after maternal infection remains poorly understood. Maternal T cells likely play a critical role in preventing infection at the maternal-fetal interface and limiting spread across the placenta, but concerns exist that immune responses to infection may also cause placental dysfunction and adverse pregnancy outcomes. This study investigated the role of CD4+ and CD8+ T cells in a guinea pig model of primary cytomegalovirus infection. Monoclonal antibodies specific to guinea pig CD4 and CD8 were used to deplete T cells in non-pregnant and in pregnant guinea pigs after mid-gestation. CD4+ T cell depletion increased the severity of illness, caused significantly elevated viral loads, and increased the rate of congenital guinea pig cytomegalovirus (GPCMV) infection relative to animals treated with control antibody. CD8+ T cell depletion was comparably well tolerated and did not significantly affect the weight of infected guinea pigs or viral loads in their blood or tissue. However, significantly more viral genomes and transcripts were detected in the placenta and decidua of CD8+ T cell depleted dams post-infection. This study corroborates earlier findings made in nonhuman primates that maternal CD4+ T cells play a critical role in limiting the severity of primary CMV infection during pregnancy while also revealing that other innate and adaptive immune responses can compensate for an absent CD8+ T cell response in α-CD8-treated guinea pigs.

Current and future strategies for the prevention and treatment of cytomegalovirus infections in transplantation.

Successful prevention and treatment of cytomegalovirus (CMV) infection remains a central focus of clinical care in solid organ and allogeneic hematopoietic cell transplantation. Over the past 5 years, pivotal clinical trials have created new paradigms in CMV prevention, including diverging approaches in HCT and SOT. We review recent advances in CMV risk assessment and progress in antiviral and immune-based strategies for CMV prevention and treatment. We highlight approaches to optimize CMV-specific immunity through vaccination, monoclonal antibodies, and virus-specific T-cells. Observational studies and interventional trials of commercially-available CMV cell-mediated immunity assays for refining preventive and treatment strategies are summarized. Finally, we discuss the importance of enhancing CMV-specific immunity to mitigate the negative impacts of CMV in different transplant settings. CMV infections in recipients of chimeric antigen receptor-T (CAR-T) cell therapies and other immunocompromised populations are growing areas of importance that are beyond the scope of this review.

Epidemiology of Infections in Lung Transplant Recipients Treated With Belatacept.

Belatacept is a costimulatory blocker that can be used to prevent and treat rejection in lung transplant recipients (LuTRs). The epidemiology of infections in belatacept-treated LuTRs has not been systematically evaluated. We performed a single-center retrospective study of all adult LuTRs who received belatacept as prevention or treatment of antibody-mediated rejection (desensitization) or as part of maintenance immunosuppression from January 1, 2011, to June 30, 2022. We assessed the epidemiology of infections that occurred within 12 months following the first belatacept dose. Fifty-two LuTRs received at least one dose of belatacept as either desensitization (n = 32) or maintenance immunosuppression (n = 20). Among 45 patients who were cytomegalovirus (CMV) donor and/or recipient seropositive, nine (20%) developed CMV infection. Seven (77%) CMV infections occurred despite valganciclovir prophylaxis and four (44%) were associated with antiviral resistance. Three (6%) LuTRs developed Epstein-Barr virus (EBV) associated post-transplant lymphoproliferative disorder (PTLD). Twenty-five (48%) LuTRs developed 43 bacterial infections and five (10%) developed proven or probable invasive fungal disease. Incidence rates of viral, bacterial, and fungal infections were similar between the desensitization and maintenance groups: incidence rate ratios (95% confidence interval) were 0.70 (0.32-1.57), 1.31 (0.70-2.46), and 2.82 (0.31-25.2), respectively. Infection/PTLD prompted belatacept discontinuation in eight (15%) patients. In the first year after belatacept initiation, LuTRs commonly developed CMV infections, EBV+ PTLD, and bacterial infections. Multicenter collaborations are needed to better understand infection risks in LuTRs treated with belatacept.

Congenital cytomegalovirus

Leena O'Hara discusses congenital cytomegalovirus, and shares the story of Melanie Hiscutt and her daughter, Hope, who was born with congenital cytomegalovirus

Risk Factors for Cytomegalovirus Infection after Haematopoietic Stem Cell Transplantation: A Meta-Analysis.

Cytomegalovirus (CMV) infection is the most common viral infection after haematopoietic stem cell transplantation (HSCT). However, studies on related risk factors give different views without any clear conclusion. Therefore, the purpose of this study was to evaluate the risk variables of CMV infection after HSCT in order to provide recommendations for therapeutic treatment. The National Knowledge Infrastructure [CNKI], Chinese Biomedical Literature database [SinoMed], Wanfang Digital Periodicals [WANFANG] and China Science and Technology Journal [VIP] databases, as well as PubMed, Embase, CENTRAL, Web of Science databases were searched. The search keyword was Cumulative Index of Nursing and Related Health Literature (CINAHL). The search time spanned from the time when the database was created to February 2023. Based on inclusion and exclusion criteria, two researchers independently chose the literature, retrieved data, and assessed the bias risk. The methodological quality of the included studies was assessed by the Newcastle Ottawa scale (NOS). A total of 1,038 literatures were retrieved, of which, 18 studies were finally included. The final results of meta-analysis showed that there were seven risk factors as follows: Acute graft-versus-host disease (aGVHD) grades II-IV (II-IV) [odds ratio = 3.39, 95% CI (2.13, 5.41), p <0.05]; ant-thymocyte globulin (ATG) administration in treatment [odds ratio = 2.53, 95% CI (1.41, 4.53), p <0.05]; cyclosporine level after transplantation (>300 ng/ml) [OR = 3.79, 95% CI (1.24, 11.65), p <0.05]; age [odds ratio = 1.83, 95% CI (1.06, 3.15), p <0.05]; neutrophil deficiency time [odds ratio = 6.58, 95% CI (2.24, 19.30), p <0.05]; CMV infection in recipients before transplantation [odds ratio = 6.32,95% CI (4.03, 9.90), p <0.05]; fungal infection [odds ratio = 2.63, 95% CI (1.09, 6.34), p <0.05]. This study preliminarily revealed that CMV infection after HSCT is related to aGVHD (II-IV), ATG administration in pretreatment, cyclosporine level (>300 ng/ml) after transplantation, age, neutrophil deficiency time, CMV infection in recipients before transplantation and fungal infection. However, the mechanisms behind the risk variables are unclear. Further research is necessary to understand the risk factors and to enhance the care of patients with these risk factors to prevent or control infection. Key Words: Haematopoietic stem cell transplantation, Cytomegalovirus infection, Risk factors, Meta-analysis.

Diagnostic et prise en charge de l'infection congénitale à cytomégalovirus

AbstractCongenital cytomegalovirus (CMV) infection affects almost 1 % of newborns, with a risk of sequelae of 17-20 %. Primary maternal infection during the first trimester of pregnancy is the most significant risk factor for severe disease. To prevent primary maternal infection, primary prevention strategies (hygiene and information measures) have been shown to be effective but are still insufficient. Although not yet recommended by the health authorities, screening enables cases of primary maternal infection to be detected as early as possible, so that transmission can be prevented by administering valaciclovir. This strategy has proved effective, reducing maternal-fetal transmission of CMV by 70 %. Screening is based on CMV serology (IgG and IgM), supplemented by IgG avidity testing if IgM are present. It is essential that screening and initiation of treatment should be as early as possible to optimize the efficacy of this strategy. PCR on amniotic fluid, proposed in the case of a first trimester maternal primary infection, can be used to diagnose fetal infection. It is also indicated in the event of abnormalities detected on ultrasound. CMV infection in newborns can be confirmed by PCR on saliva or urine, and treatment with valaganciclovir can be initiated in cases of symptomatic congenital infection.

Childhood Langerhans cell histiocytosis hematological involvement: severity associated with BRAFV600E loads

Hematological involvement (HI) is one of the life-threatening risk organs (ROs) in Langerhans cell histiocytosis (LCH). Lahey criteria have defined HI since 1975 as hemoglobin <10 g/dL and/or platelets <100 G/L and/or leukopenia (white blood cell count <4 G/L) and/or neutrophils <1.5 G/. Among the 2313 patients <18 years old enrolled in the French National Histiocytosis Registry (1983-2023), 331 developed HI (median age at diagnosis: 1 year); median follow-up lasted 8.1 years. Bone-marrow aspirate smears and biopsies may show reactive histiocytes, hemophagocytosis or myelofibrosis but never confirm the diagnosis. Fifty-eight (17%) patients developed macrophage-activation syndrome, sometimes related to acute Epstein-Barr virus or cytomegalovirus infection, sometimes months before typical LCH manifestations appeared. Hemoglobin and platelet thresholds for initiating transfusion(s) appear to accurately distinguish 2 groups: mild HI (MHI; >7 g/dL and >20 G/L, respectively) and severe HI (SHI; ≤7 g/dL and ≤20 G/L). Each entity has different organ involvements, laboratory parameters, mutational status, blood BRAFV600E loads, drug sensitivities and outcomes (respective MHI and SHI 10-year survival rates: 98% and 73%). Since 1998, mortality first declined with combination Cladribine-cytarabine therapy, and then with mitogen-activated protein-kinase inhibitors since 2014. Forty-one (12%) patients developed neurodegenerative complications that have emerged as a risk for long-term survivors. These results suggest limiting the HI-RO definition to SHI, as it encompasses almost all medical complications of LCH. Future clinical trials might demonstrate that targeted-therapy approaches would be better adapted for these patients, while MHI can be managed with classic therapies.

Sequence of events leading to medical abortion for fetal indications after 34 weeks' gestation: 23 years of experience in a single medical center.

Technical advances are rapidly improving the ability to detect anatomical malformations and genetic abnormalities during pregnancy. We aimed to identify the sequence of events leading to medical abortion ≥ 34 weeks' gestation, to determine whether the procedure could have been carried out earlier. Retrospective study of medical abortions in singleton pregnancies carried out in our department over a 23-year period from1998 to 2021. 36/4055 (0.88%) abortions were carried out ≥ 34 weeks' gestation. The indications were anatomical in 20 (55%), chromosomal or genetic in 14 (39%) and CMV infection In two. Evaluation of the sequence of events suggests that an earlier diagnosis would have been unfeasible before the third trimester in 18 cases (50%) because the disorder was developmental and ultrasound findings would not have presented earlier. By contrast, certain other cases might have been diagnosed earlier if the patient had not delayed routine screening or if screening had been administered on schedule. In this series, full adherence to local screening tests and protocols, and timely decision-making could have substantially reduced the late abortion rate by as much as half.

HCMV strain- and cell type-specific alterations in membrane contact sites point to the convergent regulation of organelle remodeling.

Viruses are ubiquitous entities that infect organisms across the kingdoms of life. While viruses can infect a range of cells, tissues, and organisms, this aspect is often not explored in cell culture analyses. There is limited information about which infection-induced changes are shared or distinct in different cellular environments. The prevalent pathogen human cytomegalovirus (HCMV) remodels the structure and function of subcellular organelles and their interconnected networks formed by membrane contact sites (MCSs). A large portion of this knowledge has been derived from fibroblasts infected with a lab-adapted HCMV strain. Here, we assess strain- and cell type-specific alterations in MCSs and organelle remodeling induced by HCMV. Integrating quantitative mass spectrometry, super-resolution microscopy, and molecular virology assays, we compare infections with lab-adapted and low-passage HCMV strains in fibroblast and epithelial cells. We determine that, despite baseline proteome disparities between uninfected fibroblast and epithelial cells, infection induces convergent changes and is remarkably similar. We show that hallmarks of HCMV infection in fibroblasts, mitochondria-endoplasmic reticulum (ER) encapsulations and peroxisome proliferation, are also conserved in infected epithelial and macrophage-like cells. Exploring cell type-specific differences, we demonstrate that fibroblasts rely on endosomal cholesterol transport while epithelial cells rely on cholesterol from the Golgi. Despite these mechanistic differences, infections in both cell types result in phenotypically similar cholesterol accumulation at the viral assembly complex. Our findings highlight the adaptability of HCMV, in that infections can be tailored to the initial cell state by inducing both shared and unique proteome alterations, ultimately promoting a unified pro-viral environment.IMPORTANCEHuman cytomegalovirus (HCMV) establishes infections in diverse cell types throughout the body and is connected to a litany of diseases associated with each of these tissues. However, it is still not fully understood how HCMV replication varies in distinct cell types. Here, we compare HCMV replication with lab-adapted and low-passage strains in two primary sites of infection, lung fibroblasts and retinal epithelial cells. We discover that, despite displaying disparate protein compositions prior to infection, these cell types undergo convergent alterations upon HCMV infection, reaching a more similar cellular state late in infection. We find that remodeling of the subcellular landscape is a pervasive feature of HCMV infection, through alterations to both organelle structure-function and the interconnected networks they form via membrane contact sites. Our findings show how HCMV infection in different cell types induces both shared and divergent changes to cellular processes, ultimately leading to a more unified state.

Clinical Characteristics and Prognostic Factors of Nephrotic Syndrome after Allogeneic Hematopoietic Stem Cell Transplantation.

Aims/Background Although the incidence of nephrotic syndrome (NS) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) is relatively low, it can significantly affect patients' quality of life and may even be life-threatening. Therefore, it is essential to investigate the clinical manifestations and prognosis of patients with NS after allo-HSCT, as well as to identify potential high-risk factors associated with this condition. Methods We investigated the incidence rate of NS in 1457 patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) at the First Affiliated Hospital, Zhejiang University School of Medicine between June 2007 and March 2020. Among these, we identified 12 patients who developed NS after allo-HSCT (NS group). For comparison, we selected a control group of 48 patients matched by gender and transplantation time who did not develop NS. Univariate and multivariate logistic regression analyses were performed using SPSS software, version 25.0 (IBM Corp., Armonk, NY, USA) to identify independent risk factors for NS. Results Among the 1457 patients, 12 (0.82%) developed post-transplantation NS, with a median onset time of 14.99 months (range: 5.39-48.43 months) after transplantation. Univariate analysis indicated that the occurrence of post-transplantation NS was significantly correlated with total cholesterol (TC) levels at 6 months post-transplantation (p = 0.041), triglycerides (TG) and TC levels at 1 year post-transplantation (p = 0.004 and p = 0.011, respectively), and cytomegalovirus (CMV) infection (p = 0.002). Multivariate analysis revealed that CMV infection (p = 0.004, odds ratio = 15.871; 95% confidence interval: 2.465-102.194) was independently associated with the development of NS. Conclusion After allo-HSCT, NS may manifest as a form of chronic graft-versus-host disease. CMV infection is a risk factor for developing NS. Effective management through the administration of calcium inhibitors and corticosteroids can enable long-term survival in these patients.

HPV and HCMV in Cervical Cancer: A Review of Their Co-Occurrence in Premalignant and Malignant Lesions

Cervical cancer remains a significant global health concern, particularly in low- and middle-income countries. While persistent infection with high-risk human papillomavirus (HR-HPV) is essential for cervical cancer development, it is not sufficient on its own, suggesting the involvement of additional cofactors. The human cytomegalovirus (HCMV) is a widespread β-herpesvirus known for its ability to establish lifelong latency and reactivate under certain conditions, often contributing to chronic inflammation and immune modulation. Emerging evidence suggests that HCMV may play a role in various cancers, including cervical cancer, through its potential to influence oncogenic pathways and disrupt host immune responses. This review explores clinical evidence regarding the co-presence of HR-HPV and HCMV in premalignant lesions and cervical cancer. The literature reviewed indicates that HCMV is frequently detected in cervical lesions, particularly in those co-infected with HPV, suggesting a potential synergistic interaction that could enhance HPV’s oncogenic effects, thereby facilitating the progression from low-grade squamous intraepithelial lesions (LSIL) to high-grade squamous intraepithelial lesions (HSIL) and invasive cancer. Although the precise molecular mechanisms were not thoroughly investigated in this review, the clinical evidence suggests the importance of considering HCMV alongside HPV in the management of cervical lesions. A better understanding of the interaction between HR-HPV and HCMV may lead to improved diagnostic, therapeutic, and preventive strategies for cervical cancer.

Survey of Post-Prophylaxis Delayed-Onset Cytomegalovirus Management Strategies Among Transplant Providers.

Preventive strategies for cytomegalovirus (CMV) in the posttransplant period have changed the pattern of CMV infections, now more commonly manifesting as late-onset occurrences known as post-prophylaxis delayed-onset CMV disease (PPDOC). We conducted a survey to investigate provider practices in managing PPDOC. A web-based provider survey on the management of PPDOC was developed using Research Electronic Data Capture (REDCap). It was distributed to the online forums of the American Society of Transplantation communities of practice (COP) for Infectious Diseases (IDCOP), Kidney and Pancreas (KPCOP), Liver and Intestinal (LICOP), and Thoracic and Critical Care (TCCOP). The survey was posted twice within a span of a month. Fifty-six respondents, comprising 50 (89%) transplant physicians and 6 (11%) transplant pharmacists, from 46 distinct transplant centers, completed the survey. Universal antiviral prophylaxis (UAP) was the predominant preventive approach for both high-risk (85%) and moderate-risk (85%) transplant recipients. Out of 56, 51 respondents completed the questions regarding management of PPDOC. Regular surveillance with nucleic acid amplification tests (NAAT) (88%) was the most commonly used approach in high-risk recipients, while symptom monitoring (73%) was the most common strategy in moderate-risk recipients. Immunologic monitoring was used only by a few respondents who found it moderately useful in high-risk recipients. Management of PPDOC was highly variable among providers and strategies differed based on patient risk profile. These findings could help shape future studies and guidelines to harmonize CMV management.

Defining a Therapeutic Target for Ganciclovir Therapy in Immunocompromised Children With Cytomegalovirus Infection: A Brief Report.

Ganciclovir and valganciclovir are first-line treatments for cytomegalovirus in immunocompromised children; however, the optimal therapeutic target remains unclear. This review identified 6 studies that showed clearance of cytomegalovirus viremia occurs with a median area under the concentration-time curve (AUC24) between 23 and 70 μg·h/mL, with no clear correlation with efficacy or toxicity.

CMV Retinitis in the Context of SARS-CoV-2 Infection: A Case Study and Comprehensive Review of Viral Interactions

Purpose: Cytomegalovirus (CMV) retinitis is a sight-threatening condition predominantly affecting immunocompromised individuals, such as those with Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS). We aimed to present an observational case report on CMV retinitis following Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection and to review the literature on the molecular and cellular changes in CMV and SARS-CoV-2 infections and how they may influence each other. Case Description: A 32-year-old man with a history of AIDS presented with decreased vision and ocular pain exacerbated by movement, beginning a day prior. Ocular examination revealed anterior uveitis, corneal endothelial edema, and retinal necrosis in the left eye. CMV retinitis was diagnosed based on positive serologic testing and a low cluster of differentiation 4 (CD4) count, with concurrent SARS-CoV-2 infection detected. Treatment included valganciclovir and topical agents, with a focus on managing CMV complications. This case highlights the potential role of SARS-CoV-2 in reactivating dormant CMV in severely immunocompromised individuals. We also discuss the implications of this interaction for immunocompromised patients, emphasizing the need for vigilant monitoring and personalized treatment strategies. Conclusions: Our case suggests that SARS-CoV-2 may trigger reactivation of CMV infection, leading to bilateral involvement in patients with low CD4 lymphocyte counts, which can result in severe visual impairment. The review discusses the molecular and cellular interactions between CMV and SARS-CoV-2, as well as risk factors, pathophysiology, and diagnostic methods for CMV retinitis, providing recommendations based on the literature findings.

Protein phosphatase 1 suppresses PKR/EIF2α signaling during human cytomegalovirus infection.

Human cytomegalovirus (HCMV) is a ubiquitous pathogen that infects the majority of the world's population. Lytic HCMV replication in immunocompromised individuals or neonates can lead to severe disease in multiple organ systems and even death. The establishment of lytic replication is driven by the first viral proteins expressed upon infection, the immediate early proteins, which play a key role in creating an intracellular environment conducive to virus replication. Two immediate early proteins, the functional orthologs pTRS1 and pIRS1, stimulate immediate early gene expression by suppressing antiviral PKR/eIF2α signaling and enhance the translation of viral mRNAs independent of PKR antagonism. To better understand the molecular functions of pTRS1, we used proximity labeling proteomics to identify proteins that interact with pTRS1 in infected cells. Multiple novel host and viral interactors were identified, including the catalytic subunits of the protein phosphatase 1 (PP1) holoenzyme. Mutations to a PP1 catalytic subunit known to disrupt binding to PP1 regulatory subunits decreased binding to pTRS1. pTRS1 immune complexes contained phosphatase activity, and inhibition of phosphatase activity in transfected or infected cells reversed the ability of pTRS1 to inhibit the antiviral kinase PKR. Depletion of individual PP1 catalytic subunits decreased virus replication and increased the phosphorylation of the PKR substrate eIF2α. Taken together, our data suggest potential novel functions for pTRS1 and define a novel role for PP1 as an antagonist of the antiviral PKR/eIF2α signaling axis during HCMV infection.IMPORTANCEThe human cytomegalovirus (HCMV) pTRS1 and pIRS1 proteins are critical regulators of HCMV replication, both during primary infection and during reactivation from viral latency. Thus, defining the molecular functions of pTRS1/pIRS1 is important for understanding the molecular events controlling HCMV replication and viral disease. These data provide new insights into potential pTRS1 functional roles, providing a starting point for others to understand new features of infected cell biology. Another important result of this study is the finding that specific protein phosphatase 1 (PP1) regulatory subunits are required to suppress PKR/eIF2α signaling, a critical cellular innate immune defense to viral infection. These data lay the groundwork for future efforts to discover therapeutics that disrupt pTRS1 interaction with PP1 allowing cellular defenses to limit HCMV replication and disease.

Proceedings of the Conference “CMV Vaccine Development—How Close Are We?” (27–28 September 2023)

Congenital cytomegalovirus (cCMV) is the most common infectious cause of disability in children, including sensorineural hearing loss. There is interest in developing a pre-conception vaccine that could confer protective immunity on a woman of child-bearing age, hence resulting in a reduced cCMV disease burden. Other populations, including solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) patients, could also benefit from CMV vaccination. To review and discuss vaccines that are in clinical development, a workshop, sponsored by the National Institutes of Health (NIH) and the National Institute of Allergy and Infectious Diseases (NIAID), was empaneled. At this workshop, correlates of protective immunity against CMV, epidemiologic features of CMV transmission, and vaccine platforms in development were reviewed. Representatives from academia, pharma, and the NIH engaged in discussion on the current state-of-the-art in CMV vaccinology. A summary of the presentations from this is provided in this report.

Beyond Awareness: Hope for a CMV Vaccine! An Introduction to the Conference, “CMV Vaccine Development—How Close Are We?” (27–28 September 2023)

Congenital cytomegalovirus (cCMV) is the most common infectious cause of disability in children. The major theme of this National Institute of Allergy and Infectious Diseases (NIAID) workshop, “CMV Vaccine Development—How Close Are We?”, was to report progress on the development of a pre-conception vaccine that could confer protective immunity for women of child-bearing age. Such a vaccine could result in a reduced cCMV disease burden, although other populations, including solid organ transplant and hematopoietic stem cell transplant patients, could benefit as well. To frame the compelling need for a cCMV vaccine, a keynote lecture by Dr. Megan Pesch, immediate past-president of the National CMV Foundation and a leading cCMV researcher from the University of Michigan, was given. This manuscript provides a summary of Dr. Pesch’s presentation from this workshop, which was written as the introductory conference report for the meeting.

Prognosis and Risks for Probable Chronic Lung Allograft Dysfunction: A Prospective Multicenter Study.

Chronic lung allograft dysfunction (CLAD) hinders lung transplant success. A 2019 consensus refined CLAD diagnosis, introducing probable or definite CLAD based on persistence of lung function decline. Outcomes and risks for probable CLAD remain uncertain. Determine the prognosis and clinical risks for probable CLAD in a prospective multicenter cohort. Clinical Trials in Organ Transplantation-20 included 745 CLAD-eligible adult lung recipients at 5 centers and applied rigorous methods to prospectively adjudicate probable CLAD. The impact of probable CLAD on graft loss was determined using a Cox model that considered CLAD as a time-dependent covariate. Regularized Cox modeling with LASSO penalty was used to evaluate donor or recipient characteristics and the occurrence and timing of posttransplant events as probable CLAD risks. Similar analyses were performed for definite CLAD. Probable CLAD occurred in 29.7% of patients at 3 years posttransplant and conferred a marked increase in risk for graft loss (unadjusted HR 4.38, p<0.001). Most patients (80%) with probable CLAD progressed to definite CLAD. Cytomegalovirus infection and specifically late presence (>90 days posttransplant) of donor-specific alloantibodies, acute rejection, acute lung injury, or organizing pneumonia contributed the greatest independent information about probable CLAD risk. Definite CLAD risks were similar. Probable CLAD identifies patients at high risk for graft loss, supporting prospective identification of this condition for early initiation of CLAD-directed interventions. More effective strategies to prevent posttransplant cytomegalovirus, inhibit allospecific immunity, and reduce tissue injury are needed to reduce probable CLAD and improve lung recipient survival.

Latent cytomegalovirus infection associates with impairments in myocardial reperfusion, left-ventricular function, and quality of life after ST-elevation myocardial infarction

Abstract Introduction Cytomegalovirus (CMV) is a ubiquitous herpesvirus affecting the majority of adults in European countries. CMV influences T-lymphocyte biology throughout life. We have previously associated CMV status with adverse left ventricular (LV) remodeling after ST-elevation myocardial infarction (STEMI) in a single-centre study. In this study, we aimed to assess the external validity of these findings. Methods This study is a retrospective analysis of 354 patients presenting with STEMI, who were recruited to A Trial of Low-Dose Adjunctive Alteplase During Primary PCI (T-TIME) and had blood samples archived. The participants underwent immediate coronary angiography and percutaneous coronary intervention (PCI), serial cardiovascular magnetic resonance (CMR) imaging at 2-7 days and 3 months post-STEMI, and serial assessment of health-related quality of life with the standardised EQ-5D visual analogue scale (VAS). CMV IgG titre was measured in cryopreserved samples from each patient, and patients were categorised as CMV negative, low-positive or high-positive. All analyses were adjusted for infarct location. Results Of 354 patients, 175 (49.4%) were CMV IgG titre negative, 89 (25.1%) were low-positive and 90 (25.4%) were high-positive. CMV+ patients were older (62.5 vs 58.7 years) and more likely to be non-White (6.7% vs 2.3%). CMV+ patients displayed several adverse outcomes. First, myocardial reperfusion was impaired. Thrombolysis in myocardial infarction (TIMI) flow grade 3 after PCI, indicating complete reperfusion, was less common in CMV+ patients (76.0% vs 84.6%; p=0.042). CMV+ patients also had a higher TIMI frame count after PCI (p=0.021), and non-significantly less ST-segment resolution at 60 minutes (38.8% vs 48.4%; p=0.066). Impaired myocardial reperfusion appeared to lead to impaired LV function, with LV ejection fraction (LVEF) measured on early CMR lower in CMV+ patients (42.6% vs 45.3%, p=0.004). At 3 months, LV function remained impaired in CMV+ patients (LVEF: 47.8% vs 49.7%; p=0.035). This was mirrored by CMV+ patients displaying higher NT-pro BNP levels at 2-7 days (1381 vs 1172pg/mL, p=0.097) and 3 months (575 vs 338pg/mL, p=0.021). Finally, impaired LV function appeared to affect quality of life. Over 3 months, in contrast to CMV-negative patients, those with the highest CMV IgG experienced almost no improvement in quality of life, measured by change in the EQ-5D VAS (negative: +9.93; high-positive: +0.70; p=0.0002). Conclusion CMV+ patients with STEMI experience worse outcomes, with impaired reperfusion, persistently reduced LV function and less improvement in health-related quality of life over 3 months. We hypothesise that the effect of CMV is mediated through immune activation. Future research should explore the mechanisms by which CMV-specific lymphocytes interact with myocardial reperfusion and repair post-STEMI.

High prevalence of cardiotropic viruses in endomyocardial biopsies from patients with inflammatory cardiomyopathy demonstrated by a novel targeted NGS approach

Abstract Background Viral infection of the heart muscle is a common cause of myocarditis and viral persistence can lead to chronic inflammatory cardiomyopathies (DCMi). A number of viruses including parvovirus B19 (B19V), adenovirus (AdV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes virus 6 (HHV-6) and enteroviruses (EV) are known to infect the myocardium, but their prevalence and role in persisting DCMi are not well understood. Virological etiologies can only be determined via endomyocardial biopsy (EMB), but the low tissue amount limits the number of conventional viral nucleic acid tests (virus-specific PCR) that can be performed in parallel. This study aimed to detect known and novel cardiotropic viruses in EMB of DCMi patients using a targeted next generation sequencing (NGS) approach. Methods A cohort of 33 patients with inflammatory cardiomyopathy (DCMi) (LVEF=29±12%) were retrospectively analyzed and compared to previous results of virus-specific PCR. DNA and RNA extracted from EMB were used for sequencing library preparation, and viral nucleic acids were enriched via a custom myBaits hybridization capture approach. Enriched libraries were sequenced on an Illumina MiSeq-platform in paired-end mode (500.000 reads/sample), and reads were taxonomically classified via Kraken2 and mapped against viral reference genomes using BWA-MEM2 or HiSat2, and subsequently deduplicated. Viral reads detected via both Kraken2 and mapping were classified as valid. Results Targeted NGS confirmed 19 out of 22 (86%) of the previous PCR-based viral detections. However, NGS was able to detect B19V DNA and RNA in an additional 11 and 15 patient samples respectively; CMV DNA/RNA in additional 5 and 4 samples respectively; EBV DNA/RNA in additional 5 and 1 samples respectively; and HHV-6 DNA/RNA in additional 3 and 1 samples respectively. Furthermore, viral reads of adenovirus type 2, adenovirus-associated virus type 2 (AAV-2), herpes viruses 7 and 8, and human parvovirus 4 were also found among the cohort. Thus, targeted NGS was able to identify 82 viral infections in a cohort of 33 DCMi patients, while only 22 were found using routine PCR tests. For routinely tested B19V, the use of the new NGS diagnostic approach improved sensitivity by 42% and specificity by 72%. Conclusions The presented NGS method represents a powerful new tool for the diagnosis of viral and inflammatory heart disease. The sensitivity is significantly higher than with conventional PCR approaches and the taxonomic classification is more specific. This enables the detection of previously false-negative routine viruses as well as potentially new cardiotropic pathogens from limited bioptic patient material – thus significantly increasing the diagnostic yield of EMB. In addition, our study demonstrates a high prevalence of non-enteroviral cardiotropic viruses in DCMi patients, shedding new light on the etiology of this heterogenous diseases and paving the way for more specific future treatments.