Multifactorial determinants of NK cell repertoire organization: insights into age, sex, KIR genotype, HLA typing, and CMV influence.

Introduction: Polymorphisms in the KIR and HLA genes contribute to the diversity of the NK cell repertoire. Extrinsic factors also play a role in modifying this repertoire. The best example is cytomegalovirus, which promotes the expansion of memory-like NK cells. However, the mechanisms governing this phenotypic structure are poorly understood. Furthermore, the influence of age and sex has been understudied. Methods: In this study, we examined these parameters in a cohort of 200 healthy volunteer blood donors, focusing on the major inhibitory KIR receptors and CD94/NKG2A, as well as the differentiation marker CD57 and the memory-like population marker NKG2C. Flow cytometry and two joint analyses, unsupervised and semi-supervised, helped define the impact of various intrinsic and extrinsic markers on the phenotypic structure of the NK cell repertoire. Results: In the KIR NK cell compartment, the KIR3DL1 gene is crucial, as unexpressed alleles lead to a repertoire dominated by KIR2D interacting only with HLA-C ligands, whereas an expressed KIR3DL1 gene allows for a greater diversity of NK cell subpopulations interacting with all HLA class I ligands. KIR2DL2 subsequently favors the KIR2D NK cell repertoire specific to C1/C2 ligands, whereas its absence promotes the expression of KIR2DL1 specific to the C2 ligand. The C2C2Bw4+ environment, marked by strong -21T motifs, favors the expansion of the NK cell population expressing only CD57, whereas the absence of HLA-A3/A11 ligands favors the population expressing only NKG2A, a population highly represented within the repertoire. The AA KIR genotype favors NK cell populations without KIR and NKG2A receptors, whereas the KIR B+ genotypes favor populations expressing KIR and NKG2A. Interestingly, we showed that women have a repertoire enriched in CD57- NK cell populations, while men have more CD57+ NK cell subpopulations. Discussion: Overall, our data demonstrate that the phenotypic structure of the NK cell repertoire follows well-defined genetic rules and that immunological history, sex, and age contribute to shaping this NK cell diversity. These elements can contribute to the better selection of hematopoietic stem cell donors and the definition of allogeneic NK cells for cell engineering in NK cell-based immunotherapy approaches.cters are displayed correctly.

Risk factors and outcomes of cytomegalovirus infection in the intensive care unit.

INTRODUCTION: Cytomegalovirus (CMV) infection has long been recognized as an important viral syndrome in the immunocompromised host. The disease is less well described in critically-ill patients. We evaluated the risk factors for the development of CMV infection in patients admitted to the intensive care unit (ICU). We also compared the outcomes of CMV infection in ICU patients to those of patients with hematological malignancies. METHODOLOGY: This is a retrospective study composed of three arms: patients admitted to the ICU with infection (ICU + / CMV + arm), patients admitted to the ICU who did not develop CMV infection (ICU + / CMV- arm, and patients with hematological malignancies on the hematology ward without CMV infection (ICU - / CMV + arm). RESULTS: Patients who were admitted to ICU for surgical causes had a decreased risk of CMV infection. On the other hand, receiving corticosteroids and vasoactive drugs was associated with an increased risk of CMV infection with adjusted odds ratios (aOR) of 2.4 and 25.3, respectively. Mortality was higher in ICU + / CMV + patients compared to ICU - / CMV + patients. In the ICU + /CMV + population, male sex and being on mechanical ventilation after CMV infection were independent predictors of mortality (aOR 4.6 and 5.0, respectively). CONCLUSIONS: CMV infection in ICU patients is a potentially serious disease requiring close attention. The findings from our study help in identifying patients in the ICU at risk for CMV infection, thereby warranting frequent screening. Patients at high risk of death (male, on mechanical ventilation) should receive prompt treatment and intensive follow-up.

Alemtuzumab induction is associated with decreased hospitalization rates in pediatric kidney transplant: A UNOS data review for safety and outcomes with common induction regimens.

BACKGROUND: We hypothesized that alemtuzumab use is safe in pediatric kidney transplant recipients (KTRs) with equivalent long-term outcomes compared to other induction agents. METHODS: Using pediatric kidney transplant recipient data in the UNOS database between January 1, 2000, and June 30, 2022, multivariate logistic regression, multivariable Cox regression, and survival analyses were utilized to estimate the likelihoods of 1st-year and all-time hospitalizations, acute rejection, CMV infection, delayed graft function (DGF), graft loss, and patient mortality among recipients of three common induction regimens (ATG, alemtuzumab, and basiliximab). RESULTS: There were no differences in acute rejection or graft failure among induction or maintenance regimens. Basiliximab was associated with lower odds of DGF in deceased donor recipients (OR 0.77 [0.60-0.99], p = .04). Mortality was increased in patients treated with steroid-containing maintenance (HR 1.3 [1.005-1.7] p = .045). Alemtuzumab induction correlated with less risk of CMV infection than ATG (OR 0.76 [0.59-0.99], p = .039). Steroid-containing maintenance conferred lower rate of PTLD compared to steroid-free maintenance (HR 0.59 [0.4-0.8] p = .001). Alemtuzumab was associated with less risk of hospitalization within 1 year (OR 0.79 [0.67-0.95] p = .012) and 5 years (HR 0.54 [0.46-0.65] p < .001) of transplantation. Steroid maintenance also decreased 5 years hospitalization risk (HR 0.78 [0.69-0.89] p < .001). CONCLUSIONS: Pediatric KTRs may be safely treated with alemtuzumab induction without increased risk of acute rejection, DGF, graft loss, or patient mortality. The decreased risk of CMV infections and lower hospitalization rates compared to other agents make alemtuzumab an attractive choice for induction in pediatric KTRs, especially in those who cannot tolerate ATG.

Cytomegalovirus drives Vδ1+ γδ T cell expansion and clonality in common variable immunodeficiency.

The function and phenotype of γδ T cells in the context of common variable immunodeficiency (CVID) has not been explored. CVID is a primary immunodeficiency disorder characterized by impaired antibody responses resulting in increased susceptibility to infections. γδ T cells are a subset of unconventional T cells that play crucial roles in host defence against infections. In this study, we aim to determine the roles and functions of γδ T cells in CVID. We observe a higher frequency of Vδ1+ γδ T cells compared to healthy controls, particularly in older patients. We also find a higher proportion of effector-memory Vδ1+ γδ T cells and a more clonal T cell receptor (TCR) repertoire in CVID. The most significant driver of the Vδ1+ γδ T cell expansion and phenotype in CVID patients is persistent cytomegalovirus (CMV) viremia. These findings provide valuable insights into γδ T cell biology and their contribution to immune defence in CVID.

Prevalence and risk factors of cytomegalovirus reactivation in critically Ill patients with COVID-19 pneumonia.

BACKGROUNDS: In critically ill patients with COVID-19, secondary infections are potentially life-threatening complications. This study aimed to determine the prevalence, clinical characteristics, and risk factors of CMV reactivation among critically ill immunocompetent patients with COVID-19 pneumonia. METHODS: A retrospective cohort study was conducted among adult patients who were admitted to ICU and screened for quantitative real-time PCR for CMV viral load in a tertiary-care hospital during the third wave of the COVID-19 outbreak in Thailand. Cox regression models were used to identify significant risk factors for developing CMV reactivation. RESULTS: A total of 185 patients were studied; 133 patients (71.9%) in the non-CMV group and 52 patients (28.1%) in the CMV group. Of all, the mean age was 64.7±13.3 years and 101 patients (54.6%) were males. The CMV group had received a significantly higher median cumulative dose of corticosteroids than the non-CMV group (301 vs 177 mg of dexamethasone, p<0.001). Other modalities of treatments for COVID-19 including anti-viral drugs, anti-cytokine drugs and hemoperfusion were not different between the two groups (p>0.05). The 90-day mortality rate for all patients was 29.1%, with a significant difference between the CMV group and the non-CMV group (42.3% vs. 24.1%, p = 0.014). Median length of stay was longer in the CMV group than non-CMV group (43 vs 24 days, p<0.001). The CMV group has detectable CMV DNA load with a median [IQR] of 4,977 [1,365-14,742] IU/mL and 24,570 [3,703-106,642] in plasma and bronchoalveolar fluid, respectively. In multivariate analysis, only a cumulative corticosteroids dose of dexamethasone ≥250 mg (HR = 2.042; 95%CI, 1.130-3.688; p = 0.018) was associated with developing CMV reactivation. CONCLUSION: In critically ill COVID-19 patients, CMV reactivation is frequent and a high cumulative corticosteroids dose is a significant risk factor for CMV reactivation, which is associated with poor outcomes. Further prospective studies are warranted to determine optimal management.

Distinct T cell responsiveness to different COVID-19 vaccines and cross-reactivity to SARS-CoV-2 variants with age and CMV status.

Introduction: Accumulating evidence indicates the importance of T cell immunity in vaccination-induced protection against severe COVID-19 disease, especially against SARS-CoV-2 Variants-of-Concern (VOCs) that more readily escape from recognition by neutralizing antibodies. However, there is limited knowledge on the T cell responses across different age groups and the impact of CMV status after primary and booster vaccination with different vaccine combinations. Moreover, it remains unclear whether age has an effect on the ability of T cells to cross-react against VOCs. Methods: Therefore, we interrogated the Spike-specific T cell responses in healthy adults of the Dutch population across different ages, whom received different vaccine types for the primary series and/or booster vaccination, using IFNÉ£ ELISpot. Cells were stimulated with overlapping peptide pools of the ancestral Spike protein and different VOCs. Results: Robust Spike-specific T cell responses were detected in the vast majority of participants upon the primary vaccination series, regardless of the vaccine type (i.e. BNT162b2, mRNA-1273, ChAdOx1 nCoV-19, or Ad26.COV2.S). Clearly, in the 70+ age group, responses were overall lower and showed more variation compared to younger age groups. Only in CMV-seropositive older adults (>70y) there was a significant inverse relation of age with T cell responses. Although T cell responses increased in all age groups after booster vaccination, Spike-specific T cell frequencies remained lower in the 70+ age group. Regardless of age or CMV status, primary mRNA-1273 vaccination followed by BNT162b2 booster vaccination showed limited booster effect compared to the BNT162b2/BNT162b2 or BNT162b2/mRNA-1273 primary-booster regimen. A modest reduction in cross-reactivity to the Alpha, Delta and Omicron BA.1, but not the Beta or Gamma variant, was observed after primary vaccination. Discussion: Together, this study shows that age, CMV status, but also the primary-booster vaccination regimen influence the height of the vaccination-induced Spike-specific T cell response, but did not impact the VOC cross-reactivity.

Behavioral Problems and Family Impact in Congenital Cytomegalovirus Infection.

We examined behavior (Child Behavior Checklist) and family functioning (Family Impact Questionnaire) in 65 children with congenital cytomegalovirus. Behavioral problems were present in 30.8%. Parents of children with moderate/severe outcomes reported strain on all areas of family functioning. Behavioral problems were associated with negative impact on parental feelings and marital/partnership relationship. Our findings inform planning support services.

Cytomegalovirus Infection in Adult Patients with Inflammatory Bowel Disease: A Literature Review.

Human cytomegalovirus (HCMV) is classified within the Herpesvirales order and is prevalent in 50%‒80% of the general population. Most carriers experience this infection without noticeable clinical symptoms. HCMV causes a lifelong latent infection that can be reactivated due to immune disorders and inflammation. The reactivation of HCMV becomes particularly significant when it coincides with inflammatory bowel disease (IBD). While cytomegalovirus (CMV) colitis in IBD patients was identified years ago, the role of CMV in triggering flare-ups, acute severe colitis, treatment resistance, and other outcomes in IBD patients experiencing CMV reactivation remains a subject of ongoing debate. In this review, we aim to address an updated insight into aspects related to the CMV colitis in IBD patients including epidemiology, risk factors, clinical features, diagnostic tests, histology, place of immunosuppressants and indications for antiviral treatment. We suggest for personalized and thorough assessment based on the disease phase and colitis severity when prescribing drugs to these patients. Furthermore, we emphasize the importance of regular patient follow-up to monitor drug side effects, ensuring treatment success, and minimizing the risk of colectomy.

Postnatal cytomegalovirus infection and pulmonary vascular disease in extremely premature infants: A case series.

BACKGROUND: Pulmonary vascular disease (PVD) is a major determinant of both morbidity and mortality in extremely low birth weight infants. It is biologically plausible that postnatal cytomegalovirus (pCMV) infection may lead to PVD in premature infants secondary to pneumonitis or via derangement of pulmonary vascular development directly through endothelial dysfunction. Uncertainty remains, however, regarding thresholds for intervention in premature infants with cardiorespiratory instability and presumed CMV infection likely secondary to the limited understanding of the natural history of the disease. METHODS/RESULTS: We describe four cases of premature infants with clinical and echocardiography features of PVD, in the setting of postnatally acquired CMV. All patients had atypical PVD trajectories, refractory to vasodilator treatment, which improved after initiation of CMV treatment. CONCLUSION: We highlight the need to consider postnatally acquired CMV infection in patients with PVD non-responsive to standard pulmonary vasodilator therapies or disease severity which is out of proportion of the usual clinical trajectory. Treatment of extremely premature infants with CMV-associated PVD may have positive impact on cardiorespiratory health, although duration of therapy remains uncertain.

Maribavir for treatment of cytomegalovirus infection in a liver-transplanted patient.

Cytomegalovirus infection (CMV) can be fatal for organ transplant recipients as shown in this case report. Maribavir is a recently approved drug, which can be used for therapy-refractory CMV infection or when other treatment options cannot be used. The patient in this case report was a CMV-infected liver transplant recipient, who developed a severe erythema and high CMV DNA during valganciclovir therapy. Toxic epidermal necrolysis was suspected. The patient was treated with maribavir, and both CMV DNA and the skin normalised. This case illustrates that maribavir is a useful alternative to other antiviral drugs for CMV infection.

Comparison of Whole Blood and Plasma for Monitoring Cytomegalovirus and Epstein-Barr Virus.

Monitoring Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infection after transplantation is recommended to enable preemptive therapy. However, the most suitable sample type remains unclear. Patients who underwent hematopoietic stem cell or liver transplantation were included in this study. Viral loads in sequential whole-blood and plasma samples were retrospectively analyzed. EBV DNA was detected more frequently in whole blood (55%) than in plasma (18%). The detection rate of CMV DNA was similar between the two sample types. The correlation of viral loads between the two sample types were 0.515 and 0.688 for EBV and CMV, respectively. Among paired samples in which EBV DNA was detected in whole blood, the plasma EBV detection rate was significantly higher in patients who underwent hematopoietic stem cell transplantation than in those who underwent liver transplantation. The viral DNA load in whole blood and plasma showed similar trends. The EBV detection rate was higher in whole blood, and a high correlation was observed between CMV DNA loads and whole blood and plasma. These results indicate that whole blood is more sensitive for monitoring both EBV and CMV, whereas plasma is a potential alternative sample for monitoring CMV.

[Clinical analysis of cytomegalovirus infection-associated hemophagocytic lymphohistiocytosis in five patients without underlying diseases].

The clinical data of five patients [one male and four female; median age: 31 (21-65) years] with cytomegalovirus (CMV)-induced hemophagocytic lymphohistiocytosis (HLH) diagnosed and treated in the First Affiliated Hospital of Nanjing Medical University were retrospectively analyzed from January 2011 to December 2020. None of the patients had any underlying disease, and all were immunocompetent. The main clinical presentations were fever in all five patients, splenomegaly in four, enlarged lymph nodes in two, liver enlargement in one, and rash in three. Pulmonary infection was found in three patients, two of whom developed respiratory failure. Two patients had jaundice. Central nervous system symptoms and gastrointestinal bleeding were observed in one case. All patients received glucocorticoids and antiviral therapy. One patient was treated with the COP (cyclophosphamide+vincristine+prednisone) chemotherapy regimen after antiviral therapy failed and he developed central nervous system symptoms. After treatment, four patients achieved remission, but the fifth pregnant patient eventually died of disease progression after delivery. CMV-associated HLH in an immunocompetent individual without underlying diseases is extremely rare, and most patients have favorable prognosis. Antiviral therapy is the cornerstone of CMV-HLH treatment.

Antiviral medications for preventing cytomegalovirus disease in solid organ transplant recipients.

BACKGROUND: The risk of cytomegalovirus (CMV) infection in solid organ transplant recipients has resulted in the frequent use of prophylaxis to prevent the clinical syndrome associated with CMV infection. This is an update of a review first published in 2005 and updated in 2008 and 2013. OBJECTIVES: To determine the benefits and harms of antiviral medications to prevent CMV disease and all-cause death in solid organ transplant recipients. SEARCH METHODS: We contacted the information specialist and searched the Cochrane Kidney and Transplant Register of Studies up to 5 February 2024 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs comparing antiviral medications with placebo or no treatment, comparing different antiviral medications or different regimens of the same antiviral medications for CMV prophylaxis in recipients of any solid organ transplant. Studies examining pre-emptive therapy for CMV infection are studied in a separate review and were excluded from this review. DATA COLLECTION AND ANALYSIS: Two authors independently assessed study eligibility, risk of bias and extracted data. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS: This 2024 update found four new studies, bringing the total number of included studies to 41 (5054 participants). The risk of bias was high or unclear across most studies, with a low risk of bias for sequence generation (12), allocation concealment (12), blinding (11) and selective outcome reporting (9) in fewer studies. There is high-certainty evidence that prophylaxis with aciclovir, ganciclovir or valaciclovir compared with placebo or no treatment is more effective in preventing CMV disease (19 studies: RR 0.42, 95% CI 0.34 to 0.52), all-cause death (17 studies: RR 0.63, 95% CI 0.43 to 0.92), and CMV infection (17 studies: RR 0.61, 95% CI 0.48 to 0.77). There is moderate-certainty evidence that prophylaxis probably reduces death from CMV disease (7 studies: RR 0.26, 95% CI 0.08 to 0.78). Prophylaxis reduces the risk of herpes simplex and herpes zoster disease, bacterial and protozoal infections but probably makes little to no difference to fungal infection, acute rejection or graft loss. No apparent differences in adverse events with aciclovir, ganciclovir or valaciclovir compared with placebo or no treatment were found. There is high certainty evidence that ganciclovir, when compared with aciclovir, is more effective in preventing CMV disease (7 studies: RR 0.37, 95% CI 0.23 to 0.60). There may be little to no difference in any outcome between valganciclovir and IV ganciclovir compared with oral ganciclovir (low certainty evidence). The efficacy and adverse effects of valganciclovir or ganciclovir were probably no different to valaciclovir in three studies (moderate certainty evidence). There is moderate certainty evidence that extended duration prophylaxis probably reduces the risk of CMV disease compared with three months of therapy (2 studies: RR 0.20, 95% CI 0.12 to 0.35), with probably little to no difference in rates of adverse events. Low certainty evidence suggests that 450 mg/day valganciclovir compared with 900 mg/day valganciclovir results in little to no difference in all-cause death, CMV infection, acute rejection, and graft loss (no information on adverse events). Maribavir may increase CMV infection compared with ganciclovir (1 study: RR 1.34, 95% CI: 1.10 to 1.65; moderate certainty evidence); however, little to no difference between the two treatments were found for CMV disease, all-cause death, acute rejection, and adverse events at six months (low certainty evidence). AUTHORS' CONCLUSIONS: Prophylaxis with antiviral medications reduces CMV disease and CMV-associated death, compared with placebo or no treatment, in solid organ transplant recipients. These data support the continued routine use of antiviral prophylaxis in CMV-positive recipients and CMV-negative recipients of CMV-positive organ transplants.

An Elastin-like Polypeptide-fusion peptide targeting capsid-tegument interface as an antiviral against cytomegalovirus infection.

The tegument protein pp150 of Human Cytomegalovirus (HCMV) is known to be essential for the final stages of virus maturation and mediates its functions by interacting with capsid proteins. Our laboratory has previously identified the critical regions in pp150 important for pp150-capsid interactions and designed peptides similar in sequence to these regions, with a goal to competitively inhibit capsid maturation. Treatment with a specific peptide (PepCR2 or P10) targeted to pp150 conserved region 2 led to a significant reduction in murine CMV (MCMV) growth in cell culture, paving the way for in vivo testing in a mouse model of CMV infection. However, the general pharmacokinetic parameters of peptides, including rapid degradation and limited tissue and cell membrane permeability, pose a challenge to their successful use in vivo. Therefore, we designed a biopolymer-stabilized elastin-like polypeptide (ELP) fusion construct (ELP-P10) to enhance the bioavailability of P10. Antiviral efficacy and cytotoxic effects of ELP-P10 were studied in cell culture, and pharmacokinetics, biodistribution, and antiviral efficacy were studied in a mouse model of CMV infection. ELP-P10 maintained significant antiviral activity in cell culture, and this conjugation significantly enhanced P10 bioavailability in mouse tissues. The fluorescently labeled ELP-P10 accumulated to higher levels in mouse liver and kidneys as compared to the unconjugated P10. Moreover, viral titers from vital organs of MCMV-infected mice indicated a significant reduction of virus load upon ELP-P10 treatment. Therefore, ELP-P10 has the potential to be developed into an effective antiviral against CMV infection.

Immunomonitoring via ELISPOT Assay Reveals Attenuated T-Cell Immunity to CMV in Immunocompromised Liver-Transplant Patients.

Assessing immune responses to cytomegalovirus (CMV) after liver transplant in patients on immunosuppressive therapy remains challenging. In this study, employing ELISPOT assays, 52 liver-transplant recipients were evaluated for antiviral T-cell activity in peripheral blood mononuclear cells (PBMCs), measuring interferon-γ (IFN-γ) secretion upon stimulation with CMV-specific peptides (CMV peptide pool, CMV IE-1, and pp65 antigens). Parameters such as stimulation index, mean spot size, and mean spot count were measured. The study found that heightened immunosuppression, especially with prednisolone in triple therapy, significantly dampened CMV-specific immune responses. This was demonstrated by decreased IFN-γ production by CMV-specific T-cells (CMV peptide pool: p = 0.036; OR = 0.065 [95% CI: 0.005-0.840], pp65 antigen: p = 0.026; OR = 0.048 [95% CI: 0.003-0.699]). Increased immunosuppression correlated with reduced IFN-γ secretion per cell, reflected in smaller mean spot sizes for the CMV peptide pool (p = 0.019). Notably, shorter post-transplant intervals correlated with diminished antiviral T-cell IFN-γ release at two years (CMV peptide pool: p = 0.019; IE antigen: p = 0.010) and five years (CMV peptide pool: p = 0.0001; IE antigen: p = 0.002; pp65 antigen: p = 0.047), as did advancing age (pp65 antigen: p = 0.016, OR = 0.932, 95% CI: 0.881-0.987). Patients with undetectable CMV antigens had a notably higher risk of CMV reactivation within six months from blood collection, closely linked with triple immunosuppression and prednisolone use. These findings highlight the intricate interplay between immunosuppression, immune response dynamics, and CMV reactivation risk, emphasizing the necessity for tailored immunosuppressive strategies to mitigate CMV reactivation in liver-transplant recipients. It can be concluded that, particularly in the early months post-transplantation, the use of prednisolone as a third immunosuppressant should be critically reconsidered. Additionally, the use of prophylactic antiviral therapy effective against CMV in this context holds significant importance.

Handling of human milk to prevent acquired cytomegalovirus infection in Japanese neonatal intensive care units: The first nationwide survey.

BACKGROUND: Human milk (HM) has been proven to provide immunological and nutritional advantages to neonates; however, acquired cytomegalovirus (CMV) infection can be associated with raw HM. In Japan, there are no standardized guidelines concerning HM handling. This cross-sectional survey was performed to reveal specific trends in HM handling in neonatal intensive care units (NICUs) in Japan. METHODS: A questionnaire was sent to 255 NICUs participating in the Japanese Neonatologist Association in May 2020. It involved HM handling practices, such as maternal screening, pasteurization, storage, and the workforce. RESULTS: Of 255 NICUs, 174 (67.8%) responded to the survey. Maternal CMV screening was carried out in 37 units (22.2%), and CMV inactivation in HM was performed in 44 units (26.5%). For CMV inactivation, a freeze-thawing method was employed in about 90% of units. In 70% of units providing CMV inactivation, CMV inactivation was conducted regardless of bodyweight and corrected gestational age of infants until the infants' discharge. Acquired CMV infection in preterm neonates was observed in 43 units (25.7%) in the survey period. CONCLUSION: A wide range of HM handling practices are used in Japanese NICUs. A national guideline for handling HM in NICUs should be created to promote the infection control of CMV.

IL-6-mediated endothelial injury impairs antiviral humoral immunity after bone marrow transplantation.

Endothelial function and integrity are compromised after allogeneic bone marrow transplantation (BMT), but how this affects immune responses broadly remains unknown. Using a preclinical model of CMV reactivation after BMT, we found compromised antiviral humoral responses induced by IL-6 signaling. IL-6 signaling in T cells maintained Th1 cells, resulting in sustained IFN-γ secretion, which promoted endothelial cell (EC) injury, loss of the neonatal Fc receptor (FcRn) responsible for IgG recycling, and rapid IgG loss. T cell-specific deletion of IL-6R led to persistence of recipient-derived, CMV-specific IgG and inhibited CMV reactivation. Deletion of IFN-γ in donor T cells also eliminated EC injury and FcRn loss. In a phase III clinical trial, blockade of IL-6R with tocilizumab promoted CMV-specific IgG persistence and significantly attenuated early HCMV reactivation. In sum, IL-6 invoked IFN-γ-dependent EC injury and consequent IgG loss, leading to CMV reactivation. Hence, cytokine inhibition represents a logical strategy to prevent endothelial injury, thereby preserving humoral immunity after immunotherapy.

Cytomegalovirus colitis as intestinal obstruction in an immunocompetent adolescent: a case report and literature review.

BACKGROUND: Cytomegalovirus infection manifests varying clinical characteristics and severity in diverse populations with different immune statuses. The signs and symptoms of gastrointestinal involvement are nonspecific. Here, we present a case of cytomegalovirus colitis in an immunocompetent adolescent, which manifested as intestinal pseud-obstruction. CASE PRESENTATION: A 15-year-old man who had contracted novel coronavirus infection one month earlier was admitted to our hospital with fever, abdominal pain, and hematochezia. His abdomen was distended, and laboratory evaluation revealed a decrease in the blood count, an increase in inflammatory indicators and hepatic impairment. Imaging shows bowel wall thickening and dilatation of the colon. A diagnosis of intestinal infection combined with acute intestinal pseud-obstruction was made. Diarrhea persisted despite conservative treatment with empirical antibiotics. A colonoscopy was performed. Pathology confirmed cytomegalovirus infection. Ganciclovir therapy was initiated, and subsequent review showed a good recovery. CONCLUSIONS: The case was diagnosed as cytomegalovirus colitis. We reviewed the reports of 9 cases of bowel obstruction, including our own, and found that the majority of the adult patients were elderly with underlying disease. Clinical and endoscopic manifestations are typically nonspecific, and imaging shows typical signs of intestinal obstruction. The final diagnosis was confirmed by pathology. Most of them have a good prognosis. We suggest that cytomegalovirus colitis can also lead to intestinal obstruction and that viral reactivation in immunocompetent individuals may be associated with inflammatory conditions and viral coinfection, particularly with the novel coronavirus.