Insights into early recovery from Long COVID-results from the German DigiHero Cohort.

65 million people worldwide are estimated to suffer from long-term symptoms after their SARS-CoV-2 infection (Long COVID). However, there is still little information about the early recovery among those who initially developed Long COVID, i.e. had symptoms 4-12 weeks after infection but no symptoms after 12 weeks. We aimed to identify associated factors with this early recovery. We used data from SARS-CoV-2-infected individuals from the DigiHero study. Participants provided information about their SARS-CoV-2 infections and symptoms at the time of infection, 4-12 weeks, and more than 12 weeks post-infection. We performed multivariable logistic regression to identify factors associated with early recovery from Long COVID and principal component analysis (PCA) to identify groups among symptoms. 5098 participants reported symptoms at 4-12 weeks after their SARS-CoV-2 infection, of which 2441 (48%) reported no symptoms after 12 weeks. Men, younger participants, individuals with mild course of acute infection, individuals infected with the Omicron variant, and individuals who did not seek medical care in the 4-12 week period after infection had a higher chance of early recovery. In the PCA, we identified four distinct symptom groups. Our results indicate differential risk of continuing symptoms among individuals who developed Long COVID. The identified risk factors are similar to those for the development of Long COVID, so people with these characteristics are at higher risk not only for developing Long COVID, but also for longer persistence of symptoms. Those who sought medical help were also more likely to have persistent symptoms.

NKp44/HLA-DP-dependent regulation of CD8 effector T cells by NK cells.

Although natural killer (NK) cells are recognized for their modulation of immune responses, the mechanisms by which human NK cells mediate immune regulation are unclear. Here, we report that expression of human leukocyte antigen (HLA)-DP, a ligand for the activating NK cell receptor NKp44, is significantly upregulated on CD8+ effector T cells, in particular in human cytomegalovirus (HCMV)+ individuals. HLA-DP+ CD8+ T cells expressing NKp44-binding HLA-DP antigens activate NKp44+ NK cells, while HLA-DP+ CD8+ T cells not expressing NKp44-binding HLA-DP antigens do not. In line with this, frequencies of HLA-DP+ CD8+ T cells are increased in individuals not encoding for NKp44-binding HLA-DP haplotypes, and contain hyper-expanded CD8+ T cell clones, compared to individuals expressing NKp44-binding HLA-DP molecules. These findings identify a molecular interaction facilitating the HLA-DP haplotype-specific editing of HLA-DP+ CD8+ T cell effector populations by NKp44+ NK cells and preventing the generation of hyper-expanded T cell clones, which have been suggested to have increased potential for autoimmunity.

The contribution of SARS-CoV-2 to the burden of acute respiratory infections in winter season 2022/2023: results from the DigiHero study.

OBJECTIVES: In winter of 2022/2023 SARS-CoV-2 had developed into one of many seasonal respiratory pathogens, causing an additional burden of acute respiratory infections (ARIs). Although testing was still widely used, many positive tests were not reported for the official statistics. Using data from a population-based cohort, we aimed to investigate the contribution of SARS-CoV-2 to the burden of ARI. METHODS: Over 70,000 participants of the German population-based DigiHero study were invited to a questionnaire about the number and time point of ARI and SARS-CoV-2 test results in winter 2022/2023. We calculated the incidence of non-severe acute respiratory syndrome (SARS) ARI, the additional contribution of SARS-CoV-2, and extrapolated the age-specific estimates to obtain the total burden of SARS-CoV-2 in Germany. RESULTS: For the winter of 2022/2023, 37,708 participants reported 54,813 ARIs, including 9358 SARS-CoV-2 infections. This translated into a cumulative incidence of 145 infections/100 persons for all ARIs, 120 infections/100 persons for non-SARS ARI, and 25 infections/100 persons for SARS ARI (+21%). CONCLUSIONS: Our estimate for ARI related to SARS-CoV-2 is consistent with the difference in all ARI between pre-pandemic years and 2022/2023. This additional burden should be considered, particularly, with respect to the implications for the work force.

Tolerability and efficacy of the cancer vaccine UV1 in patients with recurrent or metastatic PD-L1 positive head and neck squamous cell carcinoma planned for first-line treatment with pembrolizumab - the randomized phase 2 FOCUS trial.

Background: Globally, head and neck squamous cell carcinoma (HNSCC) is the seventh most common malignancy. Despite aggressive multimodal treatment approaches, recurrent and/or metastatic (R/M) disease develops in >50% of patients. In this setting, pembrolizumab was approved for patients with PD-L1 expression. However, response rates with checkpoint inhibitor monotherapy remain limited and strategies to strengthen tumor-directed immune responses are needed. Objective: The FOCUS trial is designed to estimate the effectiveness of UV1 vaccination in combination with pembrolizumab versus pembrolizumab as a single agent in patients with R/M HNSCC. Methods and analysis: The FOCUS trial is a two-armed, randomized, multicenter phase II study which was designed to evaluate the efficacy and feasibility of the hTERT-targeted cancer vaccine UV1 as add-on to pembrolizumab in the 1st line treatment of patients with R/M PD-L1 positive (combined positive score ≥1) HNSCC. Secondary objectives are the exploration of patient subgroups most likely deriving benefit from this novel combination and the establishment of liquid biopsy tumor monitoring in HNSCC. Ethics and dissemination: This clinical study was designed and will be conducted in compliance with Good Clinical Practice and in accordance with the Declaration of Helsinki. It is intended to publish the results of this study in peer-reviewed scientific journals and to present its content at academic conferences. Conclusions: A significant number of patients with R/M HNSCC are frail and may not tolerate chemotherapy, these patients may only be suitable for pembrolizumab monotherapy. However, long term disease stabilizations remain the exception and there is a need for the development of efficacious combination regimens for this patient population. The FOCUS study aims to optimize treatment of R/M HNSCC patients with this promising new treatment approach. Clinical Trial Registration: https://clinicaltrials.gov/study/NCT05075122, identifier NCT05075122.

Mutation-specific CAR T cells as precision therapy for IGLV3-21R110 expressing high-risk chronic lymphocytic leukemia.

The concept of precision cell therapy targeting tumor-specific mutations is appealing but requires surface-exposed neoepitopes, which is a rarity in cancer. B cell receptors (BCR) of mature lymphoid malignancies are exceptional in that they harbor tumor-specific-stereotyped sequences in the form of point mutations that drive self-engagement of the BCR and autologous signaling. Here, we use a BCR light chain neoepitope defined by a characteristic point mutation (IGLV3-21R110) for selective targeting of a poor-risk subset of chronic lymphocytic leukemia (CLL) with chimeric antigen receptor (CAR) T cells. We develop murine and humanized CAR constructs expressed in T cells from healthy donors and CLL patients that eradicate IGLV3-21R110 expressing cell lines and primary CLL cells, but neither cells expressing the non-pathogenic IGLV3-21G110 light chain nor polyclonal healthy B cells. In vivo experiments confirm epitope-selective cytolysis in xenograft models in female mice using engrafted IGLV3-21R110 expressing cell lines or primary CLL cells. We further demonstrate in two humanized mouse models lack of cytotoxicity towards human B cells. These data provide the basis for advanced approaches of resistance-preventive and biomarker-guided cellular targeting of functionally relevant lymphoma driver mutations sparing normal B cells.

SARS-CoV-2 vaccination may mitigate dysregulation of IL-1/IL-18 and gastrointestinal symptoms of the post-COVID-19 condition.

The rapid development of safe and effective vaccines helped to prevent severe disease courses after SARS-CoV-2 infection and to mitigate the progression of the COVID-19 pandemic. While there is evidence that vaccination may reduce the risk of developing post-COVID-19 conditions (PCC), this effect may depend on the viral variant. Therapeutic effects of post-infection vaccination have been discussed but the data for individuals with PCC remains inconclusive. In addition, extremely rare side effects after SARS-CoV-2 vaccination may resemble the heterogeneous PCC phenotype. Here, we analyze the plasma levels of 25 cytokines and SARS-CoV-2 directed antibodies in 540 individuals with or without PCC relative to one or two mRNA-based COVID-19 vaccinations as well as in 20 uninfected individuals one month after their initial mRNA-based COVID-19 vaccination. While none of the SARS-CoV-2 naïve individuals reported any persisting sequelae or exhibited PCC-like dysregulation of plasma cytokines, we detected lower levels of IL-1ß and IL-18 in patients with ongoing PCC who received one or two vaccinations at a median of six months after infection as compared to unvaccinated PCC patients. This reduction correlated with less frequent reporting of persisting gastrointestinal symptoms. These data suggest that post-infection vaccination in patients with PCC might be beneficial in a subgroup of individuals displaying gastrointestinal symptoms.

SARS-CoV-2-associated T-cell infiltration in the central nervous system.

Objectives: Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). Although an acute SARS-CoV-2 infection mainly presents with respiratory illness, neurologic symptoms and sequelae are increasingly recognised in the long-term treatment of COVID-19 patients. The pathophysiology and the neuropathogenesis behind neurologic complications of COVID-19 remain poorly understood, but mounting evidence points to endothelial dysfunction either directly caused by viral infection or indirectly by inflammatory cytokines, followed by a local immune response that may include virus-specific T cells. However, the type and role of central nervous system-infiltrating T cells in COVID-19 are complex and not fully understood. Methods: We analysed distinct anatomical brain regions of patients who had deceased as a result of COVID-19-associated pneumonia or complications thereof and performed T cell receptor Vß repertoire sequencing. Clonotypes were analysed for SARS-CoV-2 association using public TCR repertoire data. Results: Our descriptive study demonstrates that SARS-CoV-2-associated T cells are found in almost all brain areas of patients with fatal COVID-19 courses. The olfactory bulb, medulla and cerebellum were brain regions showing the most SARS-CoV-2 specific sequence patterns. Neuropathological workup demonstrated primary CD8+ T-cell infiltration with a perivascular infiltration pattern. Conclusion: Future research is needed to better define the relationship between T-cell infiltration and neurological symptoms and its long-term impact on patients' cognitive and mental health.

Ramucirumab, Avelumab, and Paclitaxel as Second-Line Treatment in Esophagogastric Adenocarcinoma: The Phase 2 RAP (AIO-STO-0218) Nonrandomized Controlled Trial.

Importance: Adding immune checkpoint inhibitors to chemotherapy has been associated with improved outcomes in metastatic esophagogastric adenocarcinoma, but treatment combinations and optimal patient selection need to be established. Objective: To investigate the efficacy and tolerability of the programmed cell death ligand 1 (PDL-1) inhibitor avelumab with paclitaxel plus ramucirumab. Design, Setting, and Participants: This multicenter, single-group, phase 2 nonrandomized controlled trial was conducted among patients with second-line metastatic esophagogastric adenocarcinoma. Patients pretreated with platinum plus fluoropyrimidine between April 2019 and November 2020 across 10 German centers (median follow-up, 27.4 months [95% CI 22.0-32.9 months]) were included. Data analysis was performed from January to December 2022. Interventions: Patients received ramucirumab at 8 mg/kg on days 1 and 15, avelumab at 10 mg/kg on days 1 and 15, and paclitaxel at 80 mg/m2 on days 1, 8, and 15 every 4 weeks. Main Outcomes and Measures: The prespecified primary end point was overall survival (OS) rate at 6 months, with the experimental therapy considered insufficiently active with an OS rate of 50% or less and a promising candidate with an OS rate of 65% or greater. Results: Of 60 enrolled patients, 59 patients (median [range] age, 64 [18-81] years; 47 males [70.7%]) were evaluable, including 30 patients with metastatic adenocarcinoma of the stomach and 29 patients with gastroesophageal junction. All patients were pretreated with platinum plus fluoropyrimidine, and 40 patients (67.8%) had received prior taxanes; 24 of 56 evaluable patients (42.9%) had a PDL-1 combined positive score (CPS) of 5 or greater, centrally assessed. The OS rate at 6 months was 71.2% (95% CI, 61.5%-83.7%). The median OS in the intention-to-treat population (59 patients) was 10.6 months (95% CI, 8.4-12.8 months) overall. Among patients assessable by central pathology, median OS was 9.4 months (95% CI, 7.2-11.7 months) in 32 patients with a PDL-1 CPS less than 5 and 14.0 months (95% CI, 6.0-22.1 months) in 24 patients with a PDL-1 CPS of 5 or greater (P = .25). Treatment was generally well tolerated, without unexpected toxicities. Patients with higher vs lower than median T cell repertoire richness showed an increased median OS of 20.4 months (95% CI, 7.7-33.0 months) compared with 8.3 months (95% CI, 3.7-12.9 months; hazard ratio, 0.43; 95% CI, 0.23-0.81; P = .008). Patients with lower vs higher than median cell-free DNA burden had a median OS of 19.2 months (95% CI, 8.9-29.6 months) compared with 7.3 months (95% CI, 3.2-11.4 months; hazard ratio, 0.30; 95% CI, 0.16-0.59; P < .001). Conclusions and relevance: In this study, the combination of avelumab with paclitaxel plus ramucirumab showed favorable efficacy and tolerability in the second-line treatment for metastatic esophagogastric adenocarcinoma. A PDL-1 CPS score of 5 or greater, cell-free DNA level less than the median, and T cell repertoire richness greater than the median were associated with increased median OS. Trial Registration: ClinicalTrials.gov Identifier: NCT03966118.

Pembrolizumab and trastuzumab in combination with FLOT in the perioperative treatment of HER2-positive, localized esophagogastric adenocarcinoma-a phase II trial of the AIO study group (AIO STO 0321).

Background: Esophagogastric adenocarcinoma (EGA) presents a substantial global health challenge as the number of cases continues to rise. The current standard approach for treating localized EGA involves a combination of triplet chemotherapy, which consists of a platinum compound, a fluoropyrimidine, and a taxane (known as FLOT), followed by surgery. In cases of metastatic EGA with HER2-positive status or in certain studies with localized EGA, the use of HER2-targeted antibodies such as trastuzumab has shown improved responses. Recently, the addition of programmed cell death protein 1 (PD-1) inhibitors, such as pembrolizumab, when combined with 5-FU, platinum-based chemotherapy, and trastuzumab, has demonstrated significant enhancements in response rates for HER2-positive metastatic EGA. However, there is currently insufficient evidence regarding this treatment approach in localized HER2-positive disease. Methods: The PHERFLOT study is an open-label, single-arm, multicenter, exploratory phase II trial designed to assess the efficacy, safety, and tolerability of perioperative pembrolizumab, FLOT, and trastuzumab in patients with previously untreated localized HER2-positive EGA. In total, 30 patients will be recruited. The co-primary end points are pathological complete response rate and disease-free survival rate after 2 years. Secondary objectives include safety and tolerability, efficacy in terms of progression-free survival and objective response rate and translational markers, such as blood-based signatures (e.g., immune repertoire changes or emergence of anti-HER2 resistance variants) or microbiota signatures that may correlate with immune activation and therapy response. Discussion: Recent evidence from phase II clinical trials demonstrated improved efficacy through the addition of trastuzumab to perioperative FLOT. Furthermore, in advanced or metastatic EGA, the combination of trastuzumab, FLOT, and the PD1-inhibitor pembrolizumab significantly improved treatment response. The PHERFLOT study aims to assess the efficacy and safety of this treatment approach in HER2-positive-localized EGA, potentially identifying a promising new perioperative regimen for localized EGA, which then needs to be confirmed within a randomized trial. Furthermore, the accompanying translational program of the study might help to improve the stratification of suitable patients and to identify potential translational targets for future clinical trials. Clinical trial registration: https://clinicaltrials.gov, identifier NCT05504720.

Regional Differences in Uptake of Vaccination against COVID-19 and Influenza in Germany: Results from the DigiHero Cohort.

During the COVID-19 pandemic in Germany, vaccination uptake exhibited considerable regional disparities. To assess the factors contributing to this variation, we examined the association of sociodemographic variables with COVID-19, COVID-19 booster, and influenza vaccination status within a cohort of 37,078 participants from 13 German federal states in the digital health cohort study commonly known as DigiHero. Our findings revealed variations in vaccination rates based on sociodemographic factors. However, these factors had limited explanatory power regarding regional differences in vaccine uptake. In contrast, we found substantial correlations between regional support of specific parties during the last local elections and the vaccination uptake at the level of each administrative district. In conclusion, sociodemographic factors alone did not suffice to explain the regional disparities in vaccine uptake. Political stances can play a major role, although the current investigation did not assess individual political orientations but rather used only an ecological approach.

Association between virus variants, vaccination, previous infections, and post-COVID-19 risk.

OBJECTIVES: The SARS-CoV-2 Omicron variant has spread rapidly and has been the dominant variant since 2022. The course of acute infection, in a vaccinated population, with Omicron is milder compared with earlier variants. However, little is known about how the occurrence of long-term symptoms after Omicron infection compared with other variants is modulated by previous infections and/or vaccinations. METHODS: Participants of the DigiHero study provided information about their SARS-CoV-2 infections, vaccinations, and symptoms 12 or more weeks after infection (post-COVID-19 condition - PCC). RESULTS: Participants infected with wildtype SARS-CoV-2 had the highest PCC risk (adjusted odds ratio [aOR] 6.44, 95% confidence interval (CI): 5.49; 7.56), followed by participants infected with Alpha and Delta compared with the reference group (individuals infected with Omicron having received three or more vaccinations). Among those infected with a specific variant, the number of preceding vaccinations was not associated with a risk reduction for PCC, whereas previous infection was strongly associated with a lower PCC risk (aOR 0.14, 95% CI 0.07; 0.25). CONCLUSIONS: While infection with Omicron is less likely to result in PCC compared with previous variants, lack of protection by vaccination suggests a substantial challenge for the healthcare system during the early endemic period. In the midterm, the protective effects of previous infections can reduce the burden of PCC.

SAM-Competitive EZH2-Inhibitors Induce Platinum Resistance by EZH2-Independent Induction of ABC-Transporters.

T-cell lymphomas are heterogeneous and rare lymphatic malignancies with unfavorable prognosis. Consequently, new therapeutic strategies are needed. The enhancer of zeste homologue 2 (EZH2) is the catalytic subunit of the polycomb repressive complex 2 and responsible for lysine 27 trimethylation of histone 3. EZH2 is overexpressed in several tumor entities including T-cell neoplasms leading to epigenetic and consecutive oncogenic dysregulation. Thus, pharmacological EZH2 inhibition is a promising target and its clinical evaluation in T-cell lymphomas shows favorable results. We have investigated EZH2 expression in two cohorts of T-cell lymphomas by mRNA-profiling and immunohistochemistry, both revealing overexpression to have a negative impact on patients' prognosis. Furthermore, we have evaluated EZH2 inhibition in a panel of leukemia and lymphoma cell lines with a focus on T-cell lymphomas characterized for canonical EZH2 signaling components. The cell lines were treated with the inhibitors GSK126 or EPZ6438 that inhibit EZH2 specifically by competitive binding at the S-adenosylmethionine (SAM) binding site in combination with the common second-line chemotherapeutic oxaliplatin. The change in cytotoxic effects under pharmacological EZH2 inhibition was evaluated revealing a drastic increase in oxaliplatin resistance after 72 h and longer periods of combinational incubation. This outcome was independent of cell type but associated to reduced intracellular platinum. Pharmacological EZH2 inhibition revealed increased expression in SRE binding proteins, SREBP1/2 and ATP binding cassette subfamily G transporters ABCG1/2. The latter are associated with chemotherapy resistance due to increased platinum efflux. Knockdown experiments revealed that this was independent of the EZH2 functional state. The EZH2 inhibition effect on oxaliplatin resistance and efflux was reduced by additional inhibition of the regulated target proteins. In conclusion, pharmacological EZH2 inhibition is not suitable in combination with the common chemotherapeutic oxaliplatin in T-cell lymphomas revealing an EZH2-independent off-target effect.

T cell repertoire breadth is associated with the number of acute respiratory infections in the LoewenKIDS birth cohort.

We set out to gain insight into peripheral blood B and T cell repertoires from 120 infants of the LoewenKIDS birth cohort to investigate potential determinants of early life respiratory infections. Low antigen-dependent somatic hypermutation of B cell repertoires, as well as low T and B cell repertoire clonality, high diversity, and high richness especially in public T cell clonotypes reflected the immunological naivety at 12 months of age when high thymic and bone marrow output are associated with relatively few prior antigen encounters. Infants with inadequately low T cell repertoire diversity or high clonality showed higher numbers of acute respiratory infections over the first 4 years of life. No correlation of T or B cell repertoire metrics with other parameters such as sex, birth mode, older siblings, pets, the onset of daycare, or duration of breast feeding was noted. Together, this study supports that-regardless of T cell functionality-the breadth of the T cell repertoire is associated with the number of acute respiratory infections in the first 4 years of life. Moreover, this study provides a valuable resource of millions of T and B cell receptor sequences from infants with available metadata for researchers in the field.

First-line treatment of unresectable or metastatic HER2 positive esophagogastric adenocarcinoma: liquid biomarker analysis of the phase 2 INTEGA trial.

BACKGROUND: The addition of nivolumab to trastuzumab and chemotherapy in first-line unresectable or metastatic HER2 positive esophagogastric adenocarcinoma (HER2+ EGA) results in long progression-free and overall survival as shown by the INTEGA (ipilimumab or FOLFOX in combination with nivolumab and trastuzumab in HER2 positive esophagogastric adenocarcinoma) trial. This trial suggested that the chemotherapy backbone is needed in an unselected HER2+ patient population. Yet, it remains an open question if there are specific patient subsets that may benefit from an enhanced immunotherapeutic but chemotherapy-free approach. METHODS: We analyzed blood T cell repertoire metrics determined by next-generation sequencing, circulating tumor cell (CTC) counts detected by CellSearch and their expression of HER2 and PD-L1 as potential liquid biomarkers predicting outcomes on ipilimumab versus FOLFOX (folinic acid, FOL, fluorouracil, F, oxaliplatin, OX) chemotherapy added to a backbone of trastuzumab and nivolumab in patients with HER2+ EGA in the INTEGA trial population. RESULTS: Patients with two out of three baseline-determined liquid biomarkers-high T cell repertoire richness, absence of CTCs or HER2-expression on CTCs-made up approximately 44% of HER2+ EGA cases and did not show compromise in efficacy if treated with a chemotherapy-free regimen. Long-term responders showing a progression-free survival of >12 months were enriched in this biomarker triad, especially if treated on the chemotherapy-free arm. CONCLUSION: Prospective validation of this liquid biomarker triad is needed to molecularly define HER2+ EGA patient subsets with different needs in the first-line systemic treatment setting.

Guideline Concordance of Treatment and Outcomes Among Adult Non-Hodgkin Lymphoma Patients in Sub-Saharan Africa: A Multinational, Population-Based Cohort.

BACKGROUND: Although non-Hodgkin lymphoma (NHL) is the 6th most common malignancy in Sub-Saharan Africa (SSA), little is known about its management and outcome. Herein, we examined treatment patterns and survival among NHL patients. METHODS: We obtained a random sample of adult patients diagnosed between 2011 and 2015 from 11 population-based cancer registries in 10 SSA countries. Descriptive statistics for lymphoma-directed therapy (LDT) and degree of concordance with National Comprehensive Cancer Network (NCCN) guidelines were calculated, and survival rates were estimated. FINDINGS: Of 516 patients included in the study, sub-classification was available for 42.1% (121 high-grade and 64 low-grade B-cell lymphoma, 15 T-cell lymphoma and 17 otherwise sub-classified NHL), whilst the remaining 57.9% were unclassified. Any LDT was identified for 195 of all patients (37.8%). NCCN guideline-recommended treatment was initiated in 21 patients. This corresponds to 4.1% of all 516 patients, and to 11.7% of 180 patients with sub-classified B-cell lymphoma and NCCN guidelines available. Deviations from guideline-recommended treatment were initiated in another 49 (9.5% of 516, 27.2% of 180). By registry, the proportion of all patients receiving guideline-concordant LDT ranged from 30.8% in Namibia to 0% in Maputo and Bamako. Concordance with treatment recommendations was not assessable in 75.1% of patients (records not traced (43.2%), traced but no sub-classification identified (27.8%), traced but no guidelines available (4.1%)). By registry, diagnostic work-up was in part importantly limited, thus impeding guideline evaluation significantly. Overall 1-year survival was 61.2% (95%CI 55.3%-67.1%). Poor ECOG performance status, advanced stage, less than 5 cycles and absence of chemo (immuno-) therapy were associated with unfavorable survival, while HIV status, age, and gender did not impact survival. In diffuse large B-cell lymphoma, initiation of guideline-concordant treatment was associated with favorable survival. INTERPRETATION: This study shows that a majority of NHL patients in SSA are untreated or undertreated, resulting in unfavorable survival. Investments in enhanced diagnostic services, provision of chemo(immuno-)therapy and supportive care will likely improve outcomes in the region.

Machine learning analysis of humoral and cellular responses to SARS-CoV-2 infection in young adults.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces B and T cell responses, contributing to virus neutralization. In a cohort of 2,911 young adults, we identified 65 individuals who had an asymptomatic or mildly symptomatic SARS-CoV-2 infection and characterized their humoral and T cell responses to the Spike (S), Nucleocapsid (N) and Membrane (M) proteins. We found that previous infection induced CD4 T cells that vigorously responded to pools of peptides derived from the S and N proteins. By using statistical and machine learning models, we observed that the T cell response highly correlated with a compound titer of antibodies against the Receptor Binding Domain (RBD), S and N. However, while serum antibodies decayed over time, the cellular phenotype of these individuals remained stable over four months. Our computational analysis demonstrates that in young adults, asymptomatic and paucisymptomatic SARS-CoV-2 infections can induce robust and long-lasting CD4 T cell responses that exhibit slower decays than antibody titers. These observations imply that next-generation COVID-19 vaccines should be designed to induce stronger cellular responses to sustain the generation of potent neutralizing antibodies.

Autoantigen-selected B cells are bystanders in spontaneous T cell-driven experimental autoimmune hepatitis.

Autoreactive B cells are considered pathogenic drivers in many autoimmune diseases; however, it is not clear whether autoimmune B cells are invariably pathogenic or whether they can also arise as bystanders of T cell-driven autoimmune pathology. Here, we studied the B cell response in an autoantigen- and CD4+ T cell-driven model of autoimmune hepatitis (AIH), the Alb-iGP_Smarta mouse in which expression of a viral model antigen (GP) in hepatocytes and its recognition by GP-specific CD4+ T cells causes spontaneous AIH-like disease. T cell-driven AIH in Alb-iGP_Smarta mice was marked by autoantibodies and hepatic infiltration of plasma cells and B cells, particularly of isotype-switched memory B cells, indicating antigen-driven selection and activation. Immunosequencing of B cell receptor repertoires confirmed B cell expansion selectively in the liver, which was most likely driven by the hepatic GP model antigen, as indicated by branched networks of connected sequences and elevated levels of IgG antibodies to GP. However, intrahepatic B cells did not produce increased levels of cytokines and their depletion with anti-CD20 antibody did not alter the CD4+ T cell response in Alb-iGP_Smarta mice. Moreover, B cell depletion did not prevent spontaneous liver inflammation and AIH-like disease in Alb-iGP_Smarta mice. In conclusion, selection and isotype-switch of liver-infiltrating B cells was dependent on the presence of CD4+ T cells recognizing liver antigen. However, recognition of hepatic antigen by CD4+ T cells and CD4+ T cell-mediated hepatitis was not dependent on B cells. Thus, autoreactive B cells can be bystanders and need not be drivers of liver inflammation in AIH.

Anxiety, depressive symptoms, and distress over the course of the war in Ukraine in three federal states in Germany.

Introduction: The Russian invasion of Ukraine and the resulting consequences are in the center of political discussions, media, and likely individual thinking of the population in Germany. Yet, the impact of this prolonged exposure on mental health is not known hitherto. Methods: Using the population based cohort study DigiHero from three federal states (Saxony-Anhalt, Saxony, and Bavaria), we assessed anxiety levels (GAD-7), depressive symptoms (PHQ-9), and distress (modified PDI) in the first weeks of war and 6 months later. Results: Of those 19,432, who responded in the first weeks of war, 13,934 (71.1%) responded also 6 months later. While anxiety and emotional distress decreased during the 6 months, their average scores were still elevated, and a substantial fraction of respondents displayed clinically relevant sequelae. Persons from low-income households were especially affected, specifically by fears related to the personal financial situation. Those who reacted with a particularly strong fear in the beginning of war were more likely to have persistent clinically relevant symptoms of depression and anxiety also 6 months later. Discussion: The Russian invasion of Ukraine is accompanied by continuing impairment of mental health in the German population. Fears surrounding the personal financial situation are a strong determinant.

Immune signatures in variant syndromes of primary biliary cholangitis and autoimmune hepatitis.

BACKGROUND: Variant syndromes of autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) share diagnostic features of both entities, but their immunological underpinnings remain largely unexplored. METHODS: We performed blood profiling of 23 soluble immune markers and immunogenetics in a cohort of 88 patients with autoimmune liver diseases (29 typical AIH, 31 typical PBC and 28 with clinically PBC/AIH variant syndromes). The association with demographical, serological and clinical features was analyzed. RESULTS: While T and B cell receptor repertoires were highly skewed in variant syndromes compared to healthy controls, these biases were not sufficiently discriminated within the spectrum of autoimmune liver diseases. High circulating checkpoint molecules sCD25, sLAG-3, sCD86 and sTim-3 discriminated AIH from PBC on top of classical parameters such as transaminases and immunoglobulin levels. In addition, a second cluster of correlated soluble immune factors encompassing essentially TNF, IFNγ, IL12p70, sCTLA-4, sPD-1 and sPD-L1 appeared characteristic of AIH. Cases with complete biochemical responses to treatment generally showed a lower level of dysregulation. Unsupervised hierarchical clustering of classical and variant syndromes identified two pathological immunotypes consisting predominantly of either AIH or PBC cases. Variant syndromes did not form a separate group, but clustered together with either classical AIH or PBC. Clinically, patient with AIH-like variant syndromes were less likely to be able discontinue immunosuppressive treatment. CONCLUSIONS: Our analyses suggest that variants of immune mediated liver diseases may represent an immunological spectrum from PBC to AIH-like disease reflected by their pattern of soluble immune checkpoint molecules rather than separate entities.

Circulating Tumor DNA in Head and Neck Squamous Cell Carcinoma.

Tumors shed cell-free DNA (cfDNA) into the plasma. "Liquid biopsies" are a diagnostic test to analyze cfDNA in order to detect minimal residual cancer, profile the genomic tumor landscape, and monitor cancers non-invasively over time. This technique may be useful in patients with head and neck squamous cell carcinoma (HNSCC) due to genetic tumor heterogeneity and limitations in imaging sensitivity. However, there are technical challenges that need to be overcome for the widespread use of liquid biopsy in the clinical management of these patients. In this review, we discuss our current understanding of HNSCC genetics and the role of cfDNA genomic analyses as an emerging precision diagnostic tool.