SARS-CoV-2 targets neurons of 3D human brain organoids.

COVID-19 pandemic caused by SARS-CoV-2 infection is a public health emergency. COVID-19 typically exhibits respiratory illness. Unexpectedly, emerging clinical reports indicate that neurological symptoms continue to rise, suggesting detrimental effects of SARS-CoV-2 on the central nervous system (CNS). Here, we show that a Düsseldorf isolate of SARS-CoV-2 enters 3D human brain organoids within 2 days of exposure. We identified that SARS-CoV-2 preferably targets neurons of brain organoids. Imaging neurons of organoids reveal that SARS-CoV-2 exposure is associated with altered distribution of Tau from axons to soma, hyperphosphorylation, and apparent neuronal death. Our studies, therefore, provide initial insights into the potential neurotoxic effect of SARS-CoV-2 and emphasize that brain organoids could model CNS pathologies of COVID-19.

Factors Associated With Vaccine-Induced T-Cell Immune Responses Against Severe Acute Respiratory Syndrome Coronavirus 2 in Kidney Transplant Recipients.

Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an important prophylactic measure in kidney transplant recipients (KTRs), but the immune response is often impaired. Here, we examined the T-cell immune response against SARS-CoV-2 in 148 KTRs after 3 or 4 vaccine doses, including 35 KTRs with subsequent SARS-CoV-2 infection. The frequency of spike-specific T cells was lower in KTRs than in immunocompetent controls and was correlated with the level of spike-specific antibodies. Positive predictors for detection of vaccine-induced T cells were detection of spike-specific antibodies, heterologous immunization with messenger RNA and a vector vaccine, and longer time after transplantation. In vaccinated KTRs with subsequent SARS-CoV-2 infection, the T-cell response was greatly enhanced and was significantly higher than in vaccinated KTRs without SARS-CoV-2 infection. Overall, the data show a correlation between impaired humoral and T-cell immunity to SARS-CoV-2 vaccination and provide evidence for greater robustness of hybrid immunity in KTRs.

The impact of BNT162b2 mRNA vaccine on adaptive and innate immune responses.

The mRNA-based BNT162b2 protects against severe disease and mortality caused by SARS-CoV-2 via induction of specific antibody and T-cell responses. Much less is known about its broad effects on immune responses against other pathogens. Here, we investigated the adaptive immune responses induced by BNT162b2 vaccination against various SARS-CoV-2 variants and its effects on the responsiveness of immune cells upon stimulation with heterologous stimuli. BNT162b2 vaccination induced effective humoral and cellular immunity against SARS-CoV-2 that started to wane after six months. We also observed long-term transcriptional changes in immune cells after vaccination. Additionally, vaccination with BNT162b2 modulated innate immune responses as measured by inflammatory cytokine production after stimulation - higher IL-1/IL-6 release and decreased IFN-α production. Altogether, these data expand our knowledge regarding the overall immunological effects of this new class of vaccines and underline the need for additional studies to elucidate their effects on both innate and adaptive immune responses.

Induction of trained immunity by influenza vaccination - impact on COVID-19.

Non-specific protective effects of certain vaccines have been reported, and long-term boosting of innate immunity, termed trained immunity, has been proposed as one of the mechanisms mediating these effects. Several epidemiological studies suggested cross-protection between influenza vaccination and COVID-19. In a large academic Dutch hospital, we found that SARS-CoV-2 infection was less common among employees who had received a previous influenza vaccination: relative risk reductions of 37% and 49% were observed following influenza vaccination during the first and second COVID-19 waves, respectively. The quadrivalent inactivated influenza vaccine induced a trained immunity program that boosted innate immune responses against various viral stimuli and fine-tuned the anti-SARS-CoV-2 response, which may result in better protection against COVID-19. Influenza vaccination led to transcriptional reprogramming of monocytes and reduced systemic inflammation. These epidemiological and immunological data argue for potential benefits of influenza vaccination against COVID-19, and future randomized trials are warranted to test this possibility.

Association of viral load with TRAIL, IP-10, CRP biomarker signature and disease severity in children with respiratory tract infection or fever without source: A prospective, multicentre cohort study.

BACKGROUND: To investigate the association of viral load (VL) with (i) tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), interferon gamma-induced protein-10, C-reactive protein, and a combinatorial score (BV score), and (ii) clinical severity. STUDY DESIGN: In this prospective, multicentre cohort substudy, children with respiratory tract infection or fever without source were enrolled. VL for influenza virus, rhinovirus, respiratory syncytial virus, and adenovirus was measured from nasopharyngeal swabs. The reference standard diagnosis was established based on expert panel adjudication. RESULTS: Of 1140 recruited patients, 333 had a virus monodetection. VL for the aggregated data set correlated with TRAIL and IP-10 levels, with the length of oxygen therapy, and inversely with the BV score. At a single viral level, only the influenza VL yielded a correlation with TRAIL, IP-10 levels, and the BV score. Children with a viral reference standard diagnosis had significantly higher VL than those with bacterial infection (p = 0.0005). Low TRAIL (incidence rate ratio [IRR] 0.6, 95% confidence interval [CI] 0.39-0.91) and young age (IRR 0.62, 95% CI 0.49-0.79) were associated with a longer hospital stay, while young age (IRR 0.33, 95% CI 0.18-0.61), low TRAIL (IRR 0.25, 95% CI 0.08-0.76), and high VL (IRR 1.16, 95% CI 1.00-1.33) were predictive of longer oxygen therapy. CONCLUSION: These findings indicate that VL correlates with biomarkers and may serve as a complementary tool pertaining to disease severity.

Odynophagia as the first symptom of monkeypox infection.

A 50-year-old patient with confirmed monkeypox infection presented with odynophagia and nocturnal dyspnea. Clinically, there was a lesion on the tongue without any skin lesions and fibrinous plaques on the right tonsil with asymmetry of the palatoglossal arch. Due to a suggested abscess in the CT scan, a tonsillectomy à chaud was performed. By pan-orthopox-specific polymerase chain reaction (PCR) the monkeypox infection was also confirmed in the tonsil tissue. Isolated oral findings may represent a monkeypox infection and should be considered as a currently important differential diagnosis, especially for patients at risks.

[Odynophagia as the first symptom of monkeypox infection]. / Odynophagie als erstes Symptom bei Affenpocken-Infektion.

A 50-year-old patient with confirmed monkeypox infection presented with odynophagia and nocturnal dyspnea. Clinically, there was a lesion on the tongue without any skin lesions and fibrinous plaques on the right tonsil with asymmetry of the palatoglossal arch. Due to a suggested abscess in the CT scan, a tonsillectomy à chaud was performed. By pan-orthopox-specific polymerase chain reaction (PCR) the monkeypox infection was also confirmed in the tonsil tissue. Isolated oral findings may represent a monkeypox infection and should be considered as a currently important differential diagnosis, especially for patients at risks.

Intensity of mycophenolate mofetil treatment is associated with an impaired immune response to SARS-CoV-2 vaccination in kidney transplant recipients.

Kidney transplant recipients (KTRs) are extremely vulnerable to SARS-CoV-2 infection and show an impaired immune response to SARS-CoV-2 vaccination. We analyzed factors related to vaccination efficiency in KTRs. In a multicenter prospective observational study (NCT04743947), IgG antibodies levels against SARS-CoV-2 spike S1 subunit and their neutralization capacity after SARS-CoV-2 vaccination were analyzed in 225 KTRs and compared to 176 controls. After the vaccination, 56 (24.9%) KTRs became seropositive of whom 68% had neutralizing antibodies. This immune response was significantly lower compared to controls (239 [78-519] BAU/ml versus 1826 [560-3180] BAU/ml for KTRs and controls, p < .0001). The strongest predictor for an impaired response was mycophenolate mofetil (MMF) treatment. Multivariate regression analysis revealed that MMF-free regimen was highly associated with seroconversion (OR 13.25, 95% CI 3.22-54.6; p < .001). In contrast, other immunosuppressive drugs had no significant influence. 187 out of 225 KTRs were treated with MMF of whom 26 (13.9%) developed antibodies. 23 of these seropositive KTRs had a daily MMF dose ≤1 g. Furthermore, higher trough MMF concentrations correlated with lower antibody titers (R -0.354, p < .001) supporting a dose-dependent unfavorable effect of MMF. Our data indicate that MMF dose modification could lead to an improved immune response.

Humoral response to SARS-CoV-2 and seasonal coronaviruses in COVID-19 patients.

We used enzyme-linked immunoassay methods to measure the prevalence and the levels of antibody responses to the nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and four seasonal human coronaviruses (HCoV-OC43, HCoV-HKU1, HCoV 229E, and HCoV-NL63) in a cohort of 115 convalescent plasma donors infected with SARS-CoV-2 (1-61 days after symptom onset) compared to antibody levels in 114 individuals with no evidence of a recent infection with SARS-CoV-2. In the humoral response to the four seasonal coronaviruses, only HCoV-HKU1- and HCoV-229E-assays showed slightly elevated antibody levels in the COVID group compared to the control group. While in the COVID-group the levels of SARS-CoV-2 antibodies correlated significantly with disease severity, no association was found in the levels of antibodies against the seasonal coronaviruses. The most striking result in both groups was that the levels of antibodies against all tested coronaviruses, including the new SARS-CoV-2 showed a highly significant correlation with each other. There seems to be an individual predisposition to a weaker or stronger humoral immune response against all known seasonal human coronaviruses including the new SARS-CoV-2, which could lead to a definition of low and high responders against human coronaviruses with potential impact on the assessment of postinfection antibody levels and protection.

Immune response to third SARS-CoV-2 vaccination in seronegative kidney transplant recipients: Possible improvement by mycophenolate mofetil reduction.

Modification of vaccination strategies is necessary to improve the immune response to SARS-CoV-2 vaccination in kidney transplant recipients (KTRs). This multicenter observational study analyzed the effects of the third SARS-CoV-2 vaccination in previously seronegative KTRs with the focus on temporary mycophenolate mofetil (MMF) dose reduction within propensity matched KTRs. 56 out of 174 (32%) previously seronegative KTRs became seropositive after the third vaccination with only three KTRs developing neutralizing antibodies against the omicron variant. Multivariate logistic regression revealed that initial antibody levels, graft function, time after transplantation and MMF trough levels had an influence on seroconversion (P < .05). After controlling for confounders, the effect of MMF dose reduction before the third vaccination was calculated using propensity score matching. KTRs with a dose reduction of ≥33% showed a significant decrease in MMF trough levels to 1.8 (1.2-2.5) µg/ml and were more likely to seroconvert than matched controls (P = .02). Therefore, a MMF dose reduction of 33% or more before vaccination is a promising approach to improve success of SARS-CoV-2 vaccination in KTRs.

High rate of clinically unrecognized SARS-CoV-2 infections in pediatric palliative care patients.

Little is known about the frequency and clinical course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in pediatric patients with severe comorbidities. In this prospective cross-sectional trial, the seroprevalence of SARS-CoV-2-IgG in patients with life-limiting conditions being treated by a large specialized pediatric palliative home-care team was determined. In order to gain insight into the infection chain, close contacts of seropositive patients were also included in the study. We analyzed the sera of 39 patients and found a 25.6% seroprevalence for SARS-CoV-2. No SARS-CoV-2 infections were known prior to the study. No significant difference was found in the symptom load between seropositive and seronegative patients during the risk period for SARS-CoV-2 infections. Of the 20 close contacts tested, only one was seropositive for SARS-CoV-2.Conclusions: Our results indicate a substantially high prevalence of silent SARS-CoV-2 infections in pediatric palliative care patients. Surprisingly, no severe outcomes were seen in this fragile patient collective with severe comorbidities. The chain of infection and thus the reason for the high frequency of SARS-CoV-2 infections in pediatric palliative care patients remain unclear. What is Known: •Even though severe disease courses of COVID-19 have been reported in children, there are yet no established risk factors for SARS-CoV-2 in pediatric patients. What is New: •In this cross-sectional seroprevalence study of palliative pediatric patients with severe life-limiting conditions, a high rate of seropositive patients (25.6%) was found. •Surprisingly, all seropositive patients were previously unrecognized, despite the severe comorbidities of our collective.

Respiratory viruses dynamics and interactions: ten years of surveillance in central Europe.

BACKGROUND: Lower respiratory tract infections are among the main causes of death. Although there are many respiratory viruses, diagnostic efforts are focused mainly on influenza. The Respiratory Viruses Network (RespVir) collects infection data, primarily from German university hospitals, for a high diversity of infections by respiratory pathogens. In this study, we computationally analysed a subset of the RespVir database, covering 217,150 samples tested for 17 different viral pathogens in the time span from 2010 to 2019. METHODS: We calculated the prevalence of 17 respiratory viruses, analysed their seasonality patterns using information-theoretic measures and agglomerative clustering, and analysed their propensity for dual infection using a new metric dubbed average coinfection exclusion score (ACES). RESULTS: After initial data pre-processing, we retained 206,814 samples, corresponding to 1,408,657 performed tests. We found that Influenza viruses were reported for almost the half of all infections and that they exhibited the highest degree of seasonality. Coinfections of viruses are frequent; the most prevalent coinfection was rhinovirus/bocavirus and most of the virus pairs had a positive ACES indicating a tendency to exclude each other regarding infection. CONCLUSIONS: The analysis of respiratory viruses dynamics in monoinfection and coinfection contributes to the prevention, diagnostic, treatment, and development of new therapeutics. Data obtained from multiplex testing is fundamental for this analysis and should be prioritized over single pathogen testing.

Age-dependent Immune Response to the Biontech/Pfizer BNT162b2 Coronavirus Disease 2019 Vaccination.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has led to the development of various vaccines. Real-life data on immune responses elicited in the most vulnerable group of vaccinees older than age 80 years old are still underrepresented despite the prioritization of the elderly in vaccination campaigns. METHODS: We conducted a cohort study with 2 age groups, young vaccinees below the age of 60 years and elderly vaccinees over the age of 80 years, to compare their antibody responses to the first and second dose of the BNT162b2 coronavirus disease 2019 vaccination. RESULTS: Although the majority of participants in both groups produced specific immunoglobulin G antibody titers against SARS-CoV-2 spike protein, titers were significantly lower in elderly participants. Although the increment of antibody levels after the second immunization was higher in elderly participants, the absolute mean titer of this group remained lower than the <60 years of age group. After the second vaccination, 31.3% of the elderly had no detectable neutralizing antibodies in contrast to the younger group, in which only 2.2% had no detectable neutralizing antibodies. CONCLUSIONS: Our data showed differences between the antibody responses raised after the first and second BNT162b2 vaccination, in particular lower frequencies of neutralizing antibodies in the elderly group. This suggests that this population needs to be closely monitored and may require earlier revaccination and/or an increased vaccine dose to ensure stronger long-lasting immunity and protection against infection.

Sensitivity of anti-SARS-CoV-2 serological assays in a high-prevalence setting.

Evaluation and power of seroprevalence studies depend on the performed serological assays. The aim of this study was to assess four commercial serological tests from EUROIMMUN, DiaSorin, Abbott, and Roche as well as an in-house immunofluorescence and neutralization test for their capability to identify SARS-CoV-2 seropositive individuals in a high-prevalence setting. Therefore, 42 social and working contacts of a German super-spreader were tested. Consistent with a high-prevalence setting, 26 of 42 were SARS-CoV-2 seropositive by neutralization test (NT), and immunofluorescence test (IFT) confirmed 23 of these 26 positive test results (NT 61.9% and IFT 54.8% seroprevalence). Four commercial assays detected anti-SARS-CoV-2 antibodies in 33.3-40.5% individuals. Besides an overall discrepancy between the NT and the commercial assays regarding their sensitivity, this study revealed that commercial SARS-CoV-2 spike-based assays are better to predict the neutralization titer than nucleoprotein-based assays are.

Rhinovirus prevalence as indicator for efficacy of measures against SARS-CoV-2.

BACKGROUND: Non-pharmaceutical measures to control the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) should be carefully tuned as they can impose a heavy social and economic burden. To quantify and possibly tune the efficacy of these anti-SARS-CoV-2 measures, we have devised indicators based on the abundant historic and current prevalence data from other respiratory viruses. METHODS: We obtained incidence data of 17 respiratory viruses from hospitalized patients and outpatients collected by 37 clinics and laboratories between 2010-2020 in Germany. With a probabilistic model for Bayes inference we quantified prevalence changes of the different viruses between months in the pre-pandemic period 2010-2019 and the corresponding months in 2020, the year of the pandemic with noninvasive measures of various degrees of stringency. RESULTS: We discovered remarkable reductions δ in rhinovirus (RV) prevalence by about 25% (95% highest density interval (HDI) [-0.35,-0.15]) in the months after the measures against SARS-CoV-2 were introduced in Germany. In the months after the measures began to ease, RV prevalence increased to low pre-pandemic levels, e.g. in August 2020 δ=-0.14 (95% HDI [-0.28,0.12]). CONCLUSIONS: RV prevalence is negatively correlated with the stringency of anti-SARS-CoV-2 measures with only a short time delay. This result suggests that RV prevalence could possibly be an indicator for the efficiency for these measures. As RV is ubiquitous at higher prevalence than SARS-CoV-2 or other emerging respiratory viruses, it could reflect the efficacy of noninvasive measures better than such emerging viruses themselves with their unevenly spreading clusters.

The Value of Torque Teno Virus (TTV) as a Marker for the Degree of Immunosuppression in Adult Patients after Hematopoietic Stem Cell Transplantation (HSCT).

Torque teno virus (TTV) is a nonenveloped, single-stranded, circular DNA virus of the family of Anelloviridae. The first contact with TTV usually occurs in early childhood, followed by persistent infection in bone marrow and lymphocytes. Increased levels of TTV-DNA are found in the serum in various states of immune deficiency. The objective of this study was to assess if monitoring of TTV viremia after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a predictive marker for immune-related clinical complications. In a retrospective study, 2054 whole-blood samples from 123 patients were tested for viral loads of TTV-DNA by real-time PCR within 345 days after allo-HSCT. We enrolled all patients who underwent allo-HSCT between September 2015 and April 2018. Clinical and laboratory data were collected and statistically analyzed. Patients with an underlying lymphatic malignancy had significantly higher torque teno (TT) viral loads compared with patients with an underlying malignant myeloid disease (P < .05). Complete remission before allo-HSCT correlated significantly with higher TT viral loads after allo-HSCT (P < .05). Myeloablative conditioning regimens led to significantly higher TT viral loads than reduced-intensity conditioning regimens (P < .05). A higher anti-thymocyte globulin (ATG) dose was associated with a significantly higher TT viral load. We did not observe any significant differences of TT viral load correlating with accompanying clinically relevant events such as virus reactivations (cytomegalovirus, Epstein-Barr virus, Adenovirus), acute graft-versus-host disease (aGVHD), relapse, or death. TT viral load after allo-HSCT did weakly correlate with T cell, T suppressor cell, T helper cell, and natural killer and B cell count. Although statistically significant differences between study groups were observed, virus reactivations, aGVHD, and clinical outcomes could not be predicted by monitoring TTV viremia. Therefore, TTV seems not to be suitable as a marker for the degree of immunosuppression or as a prognostic marker for clinically critical events in patients after allo-HSCT.

SARS-CoV-2 asymptomatic and symptomatic patients and risk for transfusion transmission.

Oral swabs, sputum, and blood samples from 18 asymptomatic and symptomatic patients with SARS-CoV-2 infection were examined using RT-PCR testing in order to assess the risk of transfusion-related transmission. In asymptomatic patients as well as patients with flu-like symptoms and fever, no SARS-CoV-2 RNA could be detected in the blood or serum despite a clearly positive result in all throat swabs. As patients with symptoms of infectious disease will not be admitted to blood donation, the risk for transfusion transmission of SARS-CoV-2 seems to be negligible.

Genetic structure of SARS-CoV-2 reflects clonal superspreading and multiple independent introduction events, North-Rhine Westphalia, Germany, February and March 2020.

We whole-genome sequenced 55 SARS-CoV-2 isolates from Germany to investigate SARS-CoV-2 outbreaks in 2020 in the Heinsberg district and Düsseldorf. While the genetic structure of the Heinsberg outbreak indicates a clonal origin, reflecting superspreading dynamics from mid-February during the carnival season, distinct viral strains were circulating in Düsseldorf in March, reflecting the city's international links. Limited detection of Heinsberg strains in the Düsseldorf area despite geographical proximity may reflect efficient containment and contact-tracing efforts.

Polar Infection of Echovirus-30 Causes Differential Barrier Affection and Gene Regulation at the Blood-Cerebrospinal Fluid Barrier.

Echovirus-30 (E-30) is responsible for the extensive global outbreaks of meningitis in children. To gain access to the central nervous system, E-30 first has to cross the epithelial blood-cerebrospinal fluid barrier. Several meningitis causing bacteria preferentially infect human choroid plexus papilloma (HIBCPP) cells in a polar fashion from the basolateral cell side. Here, we investigated the polar infection of HIBCPP cells with E-30. Both apical and basolateral infections caused a significant decrease in the transepithelial electrical resistance of HIBCPP cells. However, to reach the same impact on the barrier properties, the multiplicity of infection of the apical side had to be higher than that of the basolateral infection. Furthermore, the number of infected cells at respective time-points after basolateral infection was significantly higher compared to apical infection. Cytotoxic effects of E-30 on HIBCPP cells during basolateral infection were observed following prolonged infection and appeared more drastically compared to the apical infection. Gene expression profiles determined by massive analysis of cDNA ends revealed distinct regulation of specific genes depending on the side of HIBCPP cells' infection. Altogether, our data highlights the polar effects of E-30 infection in a human in vitro model of the blood-cerebrospinal fluid barrier leading to central nervous system inflammation.

Clearance of Treatment Refractory Adenoviremia via Adenovirus-specific Donor T-Cell Transfer During Aplasia After αßTCR-CD19-Depleted Stem Cell Transplantation.

Here, we report the case of severe adenoviremia in a 7-year-old boy with highly-resistant, acute leukemia. A combined approach of αßTCR-CD19-depleted stem cell transplantation, enabling immunosuppression-free post-transplant care, and early transfer of adenovirus-specific donor T cells during aplasia resulted in rapid and complete clearance of the treatment-refractory adenoviremia.