A replicating LCMV-based vaccine for the treatment of solid tumors.

Harnessing the immune system to eradicate tumors requires identification and targeting of tumor antigens, including tumor-specific neoantigens and tumor-associated self-antigens. Tumor-associated antigens are subject to existing immune tolerance, which must be overcome by immunotherapies. Despite many novel immunotherapies reaching clinical trials, inducing self-antigen-specific immune responses remains challenging. Here, we systematically investigate viral-vector-based cancer vaccines encoding a tumor-associated self-antigen (TRP2) for the treatment of established melanomas in preclinical mouse models, alone or in combination with adoptive T cell therapy. We reveal that, unlike foreign antigens, tumor-associated antigens require replication of lymphocytic choriomeningitis virus (LCMV)-based vectors to break tolerance and induce effective antigen-specific CD8+ T cell responses. Immunization with a replicating LCMV vector leads to complete tumor rejection when combined with adoptive TRP2-specific T cell transfer. Importantly, immunization with replicating vectors leads to extended antigen persistence in secondary lymphoid organs, resulting in efficient T cell priming, which renders previously "cold" tumors open to immune infiltration and reprograms the tumor microenvironment to "hot." Our findings have important implications for the design of next-generation immunotherapies targeting solid cancers utilizing viral vectors and adoptive cell transfer.

Autoreactive T cells targeting type II pneumocyte antigens in COVID-19 convalescent patients.

BACKGROUND: The role of autoreactive T cells on the course of Coronavirus disease-19 (COVID-19) remains elusive. Type II pneumocytes represent the main target cells of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Autoimmune responses against antigens highly expressed in type II pneumocytes may influence the severity of COVID-19 disease. OBJECTIVE: The aim of this study was to investigate autoreactive T cell responses against self-antigens highly expressed in type II pneumocytes in the blood of COVID-19 patients with severe and non-severe disease. METHODS: We collected blood samples of COVID-19 patients with varying degrees of disease severity and of pre-pandemic controls. T cell stimulation assays with peptide pools of type II pneumocyte antigens were performed in two independent cohorts to analyze the autoimmune T cell responses in patients with non-severe and severe COVID-19 disease. Target cell lysis assays were performed with lung cancer cell lines to determine the extent of cell killing by type II PAA-specific T cells. RESULTS: We identified autoreactive T cell responses against four recently described self-antigens highly expressed in type II pneumocytes, known as surfactant protein A, surfactant protein B, surfactant protein C and napsin A, in the blood of COVID-19 patients. These antigens were termed type II pneumocyte-associated antigens (type II PAAs). We found that patients with non-severe COVID-19 disease showed a significantly higher frequency of type II PAA-specific autoreactive T cells in the blood when compared to severely ill patients. The presence of high frequencies of type II PAA-specific T cells in the blood of non-severe COVID-19 patients was independent of their age. We also found that napsin A-specific T cells from convalescent COVID-19 patients could kill lung cancer cells, demonstrating the functional and cytotoxic role of these T cells. CONCLUSIONS: Our data suggest that autoreactive type II PAA-specific T cells have a protective role in SARS-CoV-2 infections and the presence of high frequencies of these autoreactive T cells indicates effective viral control in COVID-19 patients. Type II-PAA-specific T cells may therefore promote the killing of infected type II pneumocytes and viral clearance.

Immune signatures predict development of autoimmune toxicity in patients with cancer treated with immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitors (ICIs) are among the most promising treatment options for melanoma and non-small cell lung cancer (NSCLC). While ICIs can induce effective anti-tumor responses, they may also drive serious immune-related adverse events (irAEs). Identifying biomarkers to predict which patients will suffer from irAEs would enable more accurate clinical risk-benefit analysis for ICI treatment and may also shed light on common or distinct mechanisms underpinning treatment success and irAEs. METHODS: In this prospective multi-center study, we combined a multi-omics approach including unbiased single-cell profiling of over 300 peripheral blood mononuclear cell (PBMC) samples and high-throughput proteomics analysis of over 500 serum samples to characterize the systemic immune compartment of patients with melanoma or NSCLC before and during treatment with ICIs. FINDINGS: When we combined the parameters obtained from the multi-omics profiling of patient blood and serum, we identified potential predictive biomarkers for ICI-induced irAEs. Specifically, an early increase in CXCL9/CXCL10/CXCL11 and interferon-γ (IFN-γ) 1 to 2 weeks after the start of therapy are likely indicators of heightened risk of developing irAEs. In addition, an early expansion of Ki-67+ regulatory T cells (Tregs) and Ki-67+ CD8+ T cells is also likely to be associated with increased risk of irAEs. CONCLUSIONS: We suggest that the combination of these cellular and proteomic biomarkers may help to predict which patients are likely to benefit most from ICI therapy and those requiring intensive monitoring for irAEs. FUNDING: This work was primarily funded by the European Research Council, the Swiss National Science Foundation, the Swiss Cancer League, and the Forschungsförderung of the Kantonsspital St. Gallen.

Autoreactive napsin A-specific T cells are enriched in lung tumors and inflammatory lung lesions during immune checkpoint blockade.

Cancer treatment with immune checkpoint blockade (ICB) often induces immune-related adverse events (irAEs). We hypothesized that proteins coexpressed in tumors and normal cells could be antigenic targets in irAEs and herein described DITAS (discovery of tumor-associated self-antigens) for their identification. DITAS computed transcriptional similarity between lung tumors and healthy lung tissue based on single-sample gene set enrichment analysis. This identified 10 lung tissue-specific genes highly expressed in the lung tumors. Computational analysis was combined with functional T cell assays and single-cell RNA sequencing of the antigen-specific T cells to validate the lung tumor self-antigens. In patients with non-small cell lung cancer (NSCLC) treated with ICB, napsin A was a self-antigen that elicited strong CD8+ T cell responses, with ICB responders harboring higher frequencies of these CD8+ T cells compared with nonresponders. Human leukocyte antigen (HLA) class I ligands derived from napsin A were present in human lung tumors and in nontumor lung tissues, and napsin A tetramers confirmed the presence of napsin A-specific CD8+ T cells in blood and tumors of patients with NSCLC. Napsin A-specific T cell clonotypes were enriched in lung tumors and ICB-induced inflammatory lung lesions and could kill immortalized HLA-matched NSCLC cells ex vivo. Single-cell RNA sequencing revealed that these T cell clonotypes expressed proinflammatory cytokines and cytotoxic markers. Thus, DITAS successfully identified self-antigens, including napsin A, that likely mediate effective antitumor T cell responses in NSCLC and may simultaneously underpin lung irAEs.

Presence of autoantibodies in serum does not impact the occurrence of immune checkpoint inhibitor-induced hepatitis in a prospective cohort of cancer patients.

PURPOSE: Immune checkpoint inhibitor (ICI)-induced hepatitis belongs to the frequently occurring immune-related adverse events (irAEs), particularly with the combination therapy involving ipilimumab and nivolumab. However, predisposing factors predicting the occurrence of ICI-induced hepatitis are barely known. We investigated the association of preexisting autoantibodies in the development of ICI-induced hepatitis in a prospective cohort of cancer patients. METHODS: Data from a prospective biomarker cohort comprising melanoma and non-small cell lung cancer (NSCLC) patients were used to analyze the incidence of ICI-induced hepatitis, putatively associated factors, and outcome. RESULTS: 40 patients with melanoma and 91 patients with NSCLC received ICI between July 2016 and May 2019. 11 patients developed ICI-induced hepatitis (8.4%). Prior to treatment, 45.5% of patients in the hepatitis cohort and 43.8% of the control cohort showed elevated titers of autoantibodies commonly associated with autoimmune liver diseases (p = 0.82). We found two nominally significant associations between the occurrence of ICI-induced hepatitis and HLA alleles associated with autoimmune liver diseases among NSCLC patients. Of note, significantly more patients with ICI-induced hepatitis developed additional irAEs in other organs (p = 0.0001). Neither overall nor progression-free survival was affected in the hepatitis group. CONCLUSION: We found nominally significant associations of ICI-induced hepatitis with two HLA alleles. ICI-induced hepatitis showed no correlation with liver-specific autoantibodies, but frequently co-occurred with irAEs affecting other organs. Unlike other irAEs, ICI-induced hepatitis is not associated with a better prognosis.

Keratinocyte differentiation antigen-specific T cells in immune checkpoint inhibitor-treated NSCLC patients are associated with improved survival.

Immune checkpoint inhibitors (ICIs) have improved the survival of patients with non-small cell lung cancer (NSCLC) by reinvigorating tumor-specific T cell responses. However, the specificity of such T cells and the human leukocyte antigen (HLA)-associated epitopes recognized, remain elusive. In this study, we identified NSCLC T cell epitopes of recently described NSCLC-associated antigens, termed keratinocyte differentiation antigens. Epitopes of these antigens were presented by HLA-A 03:01 and HLA-C 04:01 and were associated with responses to ICI therapy. Patients with CD8+ T cell responses to these epitopes had improved overall and progression-free survival. T cells specific for such epitopes could eliminate HLA class I-matched NSCLC cells ex vivo and were enriched in patient lung tumors. The identification of novel lung cancer HLA-associated epitopes that correlate with improved ICI-dependent treatment outcomes suggests that keratinocyte-specific proteins are important tumor-associated antigens in NSCLC. These findings improve our understanding of the mechanisms of ICI therapy and may help support the development of vaccination strategies to improve ICI-based treatment of these tumors.

Prognostic role of gamma-glutamyl transferase in metastatic melanoma patients treated with immune checkpoint inhibitors.

BACKGROUND: Hepatic immune-related adverse events (irAE) including elevated liver function tests (transaminases) occur in 1.4-22.3% of melanoma patients receiving immune checkpoint inhibitors (ICPI) and constitute a potentially serious toxicity that is challenging to treat. In contrast to the liver transaminases alanine aminotransferase (ALT) and aspartate aminotransferase (AST), only little is known about the frequency and impact of gamma-glutamyl transferase (GGT) elevations. METHODS: GGT determined prior to and during therapy of metastatic melanoma patients treated with ICPI were retrospectively assessed in two independent cohorts (PD-1: n = 218, Ipi + Nivo: n = 148). Overall survival (OS) and best objective response were analyzed according to baseline and immune-related GGT (irGGT) elevations during treatment. RESULTS: In multivariate analysis, OS was reduced in patients with elevated baseline GGT (PD-1 group: hazard ratio [HR] 1.76, p = .0073; Ipi + Nivo group: HR 1.77, p = .032). Immune-related GGT elevation was recorded in 17% (PD-1 group) and 38.5% (Ipi + Nivo group). Of these patients, the majority (81 and 68%, respectively) had normal ALT and AST and showed no clinical signs of hepatotoxicity. Patients who experienced irGGT elevation had superior response (PD-1 group: odds ratio [OR] 3.57, p = .00072; Ipi + Nivo group: OR 1.74, p = .12) and OS (PD-1 group: HR 0.37, p = .0016; Ipi + Nivo group: HR 0.33, p = .00050). CONCLUSIONS: The frequency of hepatic irAE is currently underestimated. The addition of the sensitive enzyme GGT to the laboratory panel before and during therapy with ICPI allows to detect two to three times more patients developing hepatic or hepatobiliary toxicity than known so far. Immune-related GGT elevations correlate with response and favorable survival. Precis for use in the Table of Contents The frequency of hepatotoxicity under immune checkpoint blockade is currently underestimated. We suggest the addition of gamma-glutamyl transferase to the laboratory panel in checkpoint inhibitor patients for the detection of hepatobiliary toxicity.

Influence of different rehabilitative aerobic exercise programs on (anti-) inflammatory immune signalling, cognitive and functional capacity in persons with MS - study protocol of a randomized controlled trial.

BACKGROUND: Studies have shown positive effects of therapeutic exercise on motor- and cognitive function as well as on psychosocial outcomes in persons with multiple sclerosis (MS). A reduction of inflammatory stress through physical exercise has been suspected as one key mechanism, mediating the positive effects of exercise in the context of MS. The primary objective of this trial is to investigate the acute and chronic effects of different exercise modalities on (anti-)inflammatory immune signalling as well as on cognitive and functional capacity in persons with MS. METHODS: A two armed single-blind randomized controlled design will investigate 72 persons with relapsing remitting or secondary progressive MS (EDSS 3.0-6.0), during 3 weeks of inpatient rehabilitation. Participants will be randomized into either a high-intensity interval training (HIIT) or a moderate continuous training group; the latter represents the local standard therapy (ST). Both groups will exercise 3x per week. The HIIT group will perform 5 × 1.5-min high-intensive exercise bouts at 95-100% of their maximum heart rate (HRmax) followed by active breaks of unloaded pedalling (60% HRmax) for 2 min. In contrast, the ST group will exercise for 24 min continuously at 65% of HRmax. The proportion of circulating regulatory T-cells will be measured as primary outcome. Secondary outcomes comprise numbers and proportions of further immune cells including Th17-cells, soluble factors ((anti-) inflammatory cytokines, tryptophan metabolites), endurance capacity, cognitive performance, processing skills for activities of daily living, fatigue, depression and healthcare-related quality of life. Outcomes will be assessed before (T0) and after (T3) the 3-week exercise intervention program. Blood samples of T0 will be taken immediately before the first exercise session. Additionally, blood samples for the soluble factors will be collected immediately after (T1) and three hours (T2) after the first exercise session of each group. DISCUSSION: This study will be the first to investigate both acute and chronic effects of aerobic exercise on immune function and disease associated biomarkers in persons with MS. Combining biological analyses with cognitive and functional capacity assessments may contribute to a better understanding of responses to rehabilitative training, needed to improve exercise recommendations for persons with MS. TRIAL REGISTRATION: This trial was prospectively registered at ClinicalTrials.gov ( NCT03652519 ; 29 August 2018).

Shrunken pore syndrome, preeclampsia, and markers of NO metabolism in pregnant women during the first trimester.

Shrunken pore syndrome (SPS) is a condition that manifests itself as the decreased renal clearance of low-molecular-weight proteins but normal clearance of creatinine. Pregnant women with evidence of SPS during the first trimester have an increased risk of developing preeclampsia (PE). The nitric oxide (NO) metabolism markers arginine and ADMA, especially their ratio (Arg/ADMA), are recognized markers of endothelial dysfunction. The aim of this nested case-control study was to establish first-trimester reference intervals (RI) for markers of NO metabolism and to study these markers in women with evidence of SPS at the end of the first trimester. Seventy-four women were stratified in the first trimester according to evidence of SPS (SPS + or SPS-) and the occurrence of PE during subsequent pregnancy (PE + or PE-), as follows: SPS-/PE-, SPS+/PE-, SPS-/PE+, and SPS+/PE+. RIs were determined according to the CLSI EP28-A3c guidelines. Serum Arg and ADMA levels were analyzed. The Arg and ADMA concentrations did not differ among the four groups. However, women in the SPS+/PE + group had a significantly lower Arg/ADMA ratio than those in the other 3 groups (p = .02). In conclusion, we defined the first-trimester RI of Arg, ADMA and the Arg/ADMA ratio as markers of NO metabolism. Our results suggest that SPS in the first trimester predicts a pathophysiological hallmark of subsequent PE, i.e. lower NO production leading to increased vessel tone. Early identification of women at risk for later PE could lead to adaptive prophylactic interventions, such as supplementation with Arg or an NO-donor drug in order to mitigate the risk of developing PE.

High first-trimester maternal blood cystatin C levels despite normal serum creatinine predict pre-eclampsia in singleton pregnancies.

Early biochemical identification of women at high risk for the development of pre-eclampsia (PE) is still unsatisfactory. Renal markers measured during the first trimester were analysed to predict later occurrence of PE. A nested case-control study was conducted within the prospective predictive markers for the diagnosis of preeclampsia study. Pregnant women were included at the end of the first trimester and followed up until birth. Controls were matched to PE cases. Renal markers [i.e. creatinine, cystatin C (CysC), ß2 microglobulin (B2M), ß-trace protein (BTP), glomerular filtration rate estimations (eGFR) of the aforementioned markers, uric acid (UA), urea, and serum uromodulin (sUMOD)] were compared to placental growth factor (PlGF), a marker known to predict PE later in pregnancy. Reference intervals were determined for the different markers. In the 183 women (PE, n = 39; controls, n = 144), CysC, the CysC/PlGF ratio (p < .01) and UA were higher, whereas the eGFRCysC/eGFRCrea ratio (a marker of glomerular endothelial integrity and shrunken pore syndrome) and PlGF were lower in women who developed PE (p < .05 for all). Compromised filtration of the larger molecule CysC together with a normal creatinine, in a subset of PE cases (15.3%) was a unique, strong and independent predictor of later PE if the baseline CysC concentration was >0.85 mg/l. In conclusion, CysC and its derivatives as well as UA, indicating volume expansion, measured at the end of the first trimester are predictive of PE. Thus, women can be easily identified and followed as an early reduction in glomerular filtration quality poses a high risk for a subsequent development of PE.

Association of the cystatin C/creatinine ratio with the renally cleared hormones parathyroid hormone (PTH) and brain natriuretic peptide (BNP) in primary care patients: a cross-sectional study.

The ratio of cystatin C to creatinine (cysC/crea) is regarded as a marker of glomerular filtration quality and predicts mortality. It has been hypothesized that increased mortality may be mediated by the retention of biologically active substances due to shrinking glomerular pores. The present study investigated whether cysC/crea is independently associated with the levels of two renally cleared hormones, which have been linked to increased mortality. We conducted a multicenter, cross-sectional study with a random selection of general practitioners (GPs) from all GP offices in seven Swiss cantons. Markers of glomerular filtration quality were investigated together with estimated glomerular filtration rate (eGFR), albuminuria and urinary neutrophil gelatinase associated lipocalin (uNGAL) as well as two renally cleared low-molecular-weight protein hormones (i.e. BNP and PTH), Morbidity was assessed with the Charlson Comorbidity Index (CCI). A total of 1000 patients (433 males; mean age 57 ± 17 years) were included. There was a significant univariate association of BNP (r = 0.36, p < 0.001) and PTH (r = 0.18, p < 0.001) with cysC/crea. An adjusted model that accounted for kidney function (eGFR), altered glomerular structure (albuminuria), renal stress (uNGAL), and CCI showed that BNP and PTH were independently associated with cysC/crea as well as with the ratio of cystatin C-based to creatinine-based eGFR. In conclusion, in primary care patients, BNP and PTH are independently associated both with markers of glomerular filtration quality and eGFR regardless of structural kidney damage or renal stress. These findings offer an explanation, how altered glomerular filtration quality could contribute to increased mortality.

The cystatin C/creatinine ratio, a marker of glomerular filtration quality: associated factors, reference intervals, and prediction of morbidity and mortality in healthy seniors.

The ratio of cystatin C (cysC) to creatinine (crea) is regarded as a marker of glomerular filtration quality associated with cardiovascular morbidities. We sought to determine reference intervals for serum cysC-crea ratio in seniors. Furthermore, we sought to determine whether other low-molecular weight molecules exhibit a similar behavior in individuals with altered glomerular filtration quality. Finally, we investigated associations with adverse outcomes. A total of 1382 subjectively healthy Swiss volunteers aged 60 years or older were enrolled in the study. Reference intervals were calculated according to Clinical & Laboratory Standards Institute (CLSI) guideline EP28-A3c. After a baseline exam, a 4-year follow-up survey recorded information about overall morbidity and mortality. The cysC-crea ratio (mean 0.0124 ± 0.0026 mg/µmol) was significantly higher in women and increased progressively with age. Other associated factors were hemoglobin A1c, mean arterial pressure, and C-reactive protein (P < 0.05 for all). Participants exhibiting shrunken pore syndrome had significantly higher ratios of 3.5-66.5 kDa molecules (brain natriuretic peptide, parathyroid hormone, ß2-microglobulin, cystatin C, retinol-binding protein, thyroid-stimulating hormone, α1-acid glycoprotein, lipase, amylase, prealbumin, and albumin) and creatinine. There was no such difference in the ratios of very low-molecular weight molecules (urea, uric acid) to creatinine or in the ratios of molecules larger than 66.5 kDa (transferrin, haptoglobin) to creatinine. The cysC-crea ratio was significantly predictive of mortality and subjective overall morbidity at follow-up in logistic regression models adjusting for several factors. The cysC-crea ratio exhibits age- and sex-specific reference intervals in seniors. In conclusion, the cysC-crea ratio may indicate the relative retention of biologically active low-molecular weight compounds and can independently predict the risk for overall mortality and morbidity in the elderly.

Incidence of preeclampsia in pregnant Swiss women.

QUESTION UNDER STUDY: The epidemiology of preeclampsia in Switzerland is known only from a retrospective registry study. This analysis aimed to prospectively determine the incidence of preeclampsia in a cohort of pregnant women in Switzerland. METHODS: Pregnant women presenting at gestational week 11-14 at their obstetrician's office were consecutively included and prospectively followed-up until the end of pregnancy. Ultrasound characteristics, blood pressure measurements, body mass index, and personal history were recorded. Duration of pregnancy, occurrence of preeclampsia, birth weight and Apgar scores were recorded as outcomes. RESULTS: There were 1,300 pregnancies with follow-up available for analysis. Median age was 30 years (interquartile range [IQR] 27-33), median body mass index (BMI) 23.3 kg/m² (IQR 21.2-26.1), median systolic blood pressure 117 mm Hg (IQR 109-126) and median diastolic blood pressure 70 mm Hg (IQR 64-77). A total of 30 women developed preeclampsia, corresponding to an incidence of 2.31% (95% confidence interval [CI] 1.62%-3.28%). Of the women with preeclampsia, 6.66% (95% CI 2.04%-21.42%) had early-onset preeclampsia, 13.33% (95% CI 5.45%-29.83%) progressed to eclampsia, whereas 10% (95% CI 3.63%-28.75%) developed HELLP syndrome (haemolysis, elevated liver enzymes, low platelet count). Nulliparity and prior history of preeclampsia were more frequently seen in pregnancies with preeclampsia than in pregnancies without preeclampsia. BMI, as well as systolic and diastolic blood pressure were higher in pregnancies subsequently developing preeclampsia. CONCLUSION: The incidence of preeclampsia in Switzerland is in line with frequencies observed elsewhere in the world. Extrapolation to a national level indicates that about 1,911 (range 1,340-2,713) preeclampsia cases per year can be expected to occur in Switzerland.