Diagnostic Performance of Two Different Techniques to Quantify CMV-Specific Cell-Mediated Immunity in Intermediate-Risk Seropositive Kidney Transplant Recipients.

Background: Kidney transplant (KT) recipients at intermediate risk for cytomegalovirus (CMV) infection constitute a potential target for individualized prevention strategies informed by the CMV-specific cell-mediated immunity (CMV-CMI). The optimal method for the functional assessment of CMV-CMI in this group remains unclear.

Methods: We included 74 CMV-seropositive KT recipients that did not receive T-cell-depleting induction and were managed by preemptive therapy.

Cytomegalovirus UL44 protein induces a potent T-cell immune response in mice.

Due to the severity of CMV infection in immunocompromised individuals the development of a vaccine has been declared a priority. However, despite the efforts made there is no yet a vaccine available for clinical use. We designed an approach to identify new CMV antigens able to inducing a broad immune response that could be used in future vaccine formulations.

Hygiene-based measures for the prevention of cytomegalovirus infection in pregnant women: a systematic review.

Background: Human Cytomegalovirus (HCMV) is the most frequent congenital infection worldwide causing important sequelae. However, no vaccine or antiviral treatments are currently available, thus interventions are restricted to behavioral measures. The aim of this systematic review was to assess evidence from available intervention studies using hygiene-based measures to prevent HCMV infection during pregnancy.

Dynamics and Clinical Significance of Cytomegalovirus-Specific Neutralizing Antibodies in Kidney Transplant Recipients Treated with T-Cell-Depleting Agents.

We measured cytomegalovirus (CMV)-specific antibodies that neutralize epithelial cell infection (CMV-AbNEIs) in 101 CMV-seropositive kidney transplant recipients (KTRs) at baseline and posttransplant months 3 and 6. All the patients received antithymocyte globulin and 3-month valganciclovir prophylaxis. There were no significant differences in pretransplant AbNEIs titers between KTRs that developed or did not develop any-level CMV infection or the composite of high-level infection and/or disease.

Novel monoclonal antibody-based therapies: implications for the treatment and prevention of HCMV disease.

Human cytomegalovirus (HCMV) is an important pathogen worldwide. Although HCMV infection is often asymptomatic in immunocompetent individuals, it can cause severe or even life-threatening symptoms in immunocompromised patients. Due to limitations of antiviral treatments, it is necessary to search for new therapeutic alternatives.

Identification and Characterization of Epithelial Cell-Derived Dense Bodies Produced upon Cytomegalovirus Infection.

Dense bodies (DB) are complex, noninfectious particles produced during CMVinfection containing envelope and tegument proteins that may be ideal candidates as vaccines. Although DB were previously described in fibroblasts, no evidence of DB formation has been shown after propagating CMV in epithelial cells. In the present study, both fibroblast MRC-5 and epithelial ARPE-19 cells were used to study DB production during CMV infection.

Corrigendum: Brief Research Report: Virus-Specific Humoral Immunity at Admission Predicts the Development of Respiratory Failure in Unvaccinated SARS-CoV-2 Patients.

[This corrects the article DOI: 10.3389/fimmu.2022.

Brief Research Report: Virus-Specific Humoral Immunity at Admission Predicts the Development of Respiratory Failure in Unvaccinated SARS-CoV-2 Patients.

Introduction: There is robust evidence indicating that the SARS-CoV-2-specific humoral response is associated with protection against severe disease. However, relatively little data exist regarding how the humoral immune response at the time of hospital admission correlates with disease severity in unimmunized patients. Our goal was toidentify variables of the humoral response that could potentially serve as prognostic markers for COVID-19 progressionin unvaccinated SARS-CoV-2 patients.

Cross-Recognition of SARS-CoV-2 B-Cell Epitopes with Other Betacoronavirus Nucleoproteins.

The B and T lymphocytes of the adaptive immune system are important for the control of most viral infections, including COVID-19. Identification of epitopes recognized by these cells is fundamental for understanding how the immune system detects and removes pathogens, and for antiviral vaccine design. Intriguingly, several cross-reactive T lymphocyte epitopes from SARS-CoV-2 with other betacoronaviruses responsible for the common cold have been identified.

Isolation of Functional SARS-CoV-2 Antigen-Specific T-Cells with Specific Viral Cytotoxic Activity for Adoptive Therapy of COVID-19.

In order to demonstrate the feasibility of preparing clinical-grade SARS-CoV-2-specific T-cells from convalescent donors and the ability of these cells to neutralize the virus in vitro, we used blood collected from two COVID-19 convalescent donors (before and after vaccination) that was stimulated with specific SARS-CoV-2 peptides followed by automated T-cell isolation using the CliniMacs Prodigy medical device. To determine cytotoxic activity, HEK 293T cells were transfected to express the SARS-CoV-2 M protein, mimicking SARS-CoV-2 infection. We were able to quickly and efficiently isolate SARS-CoV-2-specific T lymphocytes from both donors before and after they received the Pfizer-BioNTech vaccine.

Deciphering the Potential Coding of Human Cytomegalovirus: New Predicted Transmembrane Proteome.

CMV is a major cause of morbidity and mortality in immunocompromised individuals that will benefit from the availability of a vaccine. Despite the efforts made during the last decade, no CMV vaccine is available. An ideal CMV vaccine should elicit a broad immune response against multiple viral antigens including proteins involved in virus-cell interaction and entry.

Discordance Between SARS-CoV-2-specific Cell-mediated and Antibody Responses Elicited by mRNA-1273 Vaccine in Kidney and Liver Transplant Recipients.

Unlabelled: Severe acute respiratory syndrome coronavirus 2-specific cell-mediated immunity (SARS-CoV-2-CMI) elicited by mRNA-based vaccines in solid organ transplant (SOT) recipients and its correlation with antibody responses remain poorly characterized.

Methods: We included 44 (28 kidney, 14 liver, and 2 double organ) recipients who received the full series of the mRNA-1273 vaccine. SARS-CoV-2-CMI was evaluated at baseline, before the second dose, and at 2 wk after completion of vaccination by an ELISpot-based interferon-γ FluoroSpot assay using overlapping peptides covering the S1 domain.

Immunogenicity of Anti-SARS-CoV-2 Vaccines in Common Variable Immunodeficiency.

Common variable immunodeficiency (CVID) is characterized by hypogammaglobulinemia and/or a defective antibody response to T-dependent and T-independent antigens. CVID response to immunization depends on the antigen type, the vaccine mechanism, and the specific patient immune defect. In CVID patients, humoral and cellular responses to the currently used COVID-19 vaccines remain unexplored.

Optimization of a Lambda-RED Recombination Method for Rapid Gene Deletion in Human Cytomegalovirus.

Human cytomegalovirus (HCMV) continues to be a major cause of morbidity in transplant patients and newborns. However, the functions of many of the more than 282 genes encoded in the HCMV genome remain unknown. The development of bacterial artificial chromosome (BAC) technology contributes to the genetic manipulation of several organisms including HCMV.

Circulatory follicular helper T lymphocytes associate with lower incidence of CMV infection in kidney transplant recipients.

Primary infection and/or reactivation of cytomegalovirus (CMV) in kidney transplant recipients (KTR) favor rejection and mortality. T follicular helper cells (TFH) could contribute to protection against CMV. Circulatory TFH (cTFH) were studied pretransplant and early posttransplant in 90 CMV seropositive KTR not receiving antithymocyte globulin or antiviral prophylaxis, followed-up for 1 year.

Is It Feasible to Use CMV-Specific T-Cell Adoptive Transfer as Treatment Against Infection in SOT Recipients?

During the last decade, many studies have demonstrated the role of CMV specific T-cell immune response on controlling CMV replication and dissemination. In fact, it is well established that transplanted patients lacking CMV-specific T-cell immunity have an increased occurrence of CMV replication episodes and CMV-related complications. In this context, the use of adoptive transfer of CMV-specific T-cells has been widely investigated and applied to Hematopoietic Stem Cell Transplant patients and may be useful as a therapeutic alternative, to reconstitute the CMV specific T-cell response and to control CMV viremia in patients receiving a transplantation.

Pre-existing Hemagglutinin Stalk Antibodies Correlate with Protection of Lower Respiratory Symptoms in Flu-Infected Transplant Patients.

Hemagglutination-inhibitory antibodies are usually highly strain specific with little effect on infection with drifted or shifted strains. The significance of broadly cross-reactive non-HAI anti-influenza antibodies against conserved domains of virus glycoproteins, such as the hemagglutinin (HA) stalk, is of great interest. We characterize a cohort of 40 H1N1pmd09 influenza-infected patients and identify lower respiratory symptoms (LRSs) as a predictor for development of pneumonia.

Effect of Influenza Vaccination Inducing Antibody Mediated Rejection in Solid Organ Transplant Recipients.

Introduction: Our goal was to study whether influenza vaccination induced antibody mediated rejection in a large cohort of solid organ transplant recipients (SOTR).

Methods: Serum anti-Human Leukocyte Antigen (HLA) antibodies were determined using class I and class II antibody-coated latex beads (FlowPRA Screening Test) by flow cytometry. Anti-HLA antibody specificity was determined using the single-antigen bead flow cytometry (SAFC) assay and assignation of donor specific antibodies (DSA) was performed by virtual-crossmatch.

Role of Neutralizing Antibodies in CMV Infection: Implications for New Therapeutic Approaches.

Cytomegalovirus (CMV) infection elicits a potent immune response that includes the stimulation of antibodies with neutralizing activity. Recent studies have focused on elucidating the role of neutralizing antibodies in protecting against CMV infection and disease and characterizing viral antigens against which neutralizing antibodies are directed. Here, we provide a synthesis of recent data regarding the role of neutralizing antibodies in protection against CMV infection/disease.

Varicella-zoster virus clades circulating in Spain over two decades.

Background: Despite childhood universal VZV immunization was introduced in 2015, there are no data on VZV clade distribution in Spain.

Objectives: To characterize the varicella-zoster virus strains circulating in Spain between 1997 and 2016.

Study Design: In this retrospective study, we determined the VZV clades in 294 patients with different pathologies (mainly encephalitis, zoster and varicella) by sequencing three fragments within ORF 22, ORF 21 and ORF 50 and, subsequently analyzing 7 relevant SNPs.

Going beyond serology for stratifying the risk of CMV infection in transplant recipients.

Knowledge of donor and recipient (D/R) cytomegalovirus (CMV) serostatus is critical for risk stratification of CMV infection and disease in transplant recipients, particularly in the solid organ transplantation (SOT) setting. Despite its broad availability and the success of it use, the risk stratification based on the D/R serostatus is not free of limitations since there are a nondepreciable number of patients that are not accurately categorized by this approach. In fact, up to 20% of seropositive SOT recipients, classically considered at intermediate risk, develop episodes of CMV infection and disease after transplantation.