Time-resolved single-cell transcriptomics defines immune trajectories in glioblastoma.

Deciphering the cell-state transitions underlying immune adaptation across time is fundamental for advancing biology. Empirical in vivo genomic technologies that capture cellular dynamics are currently lacking. We present Zman-seq, a single-cell technology recording transcriptomic dynamics across time by introducing time stamps into circulating immune cells, tracking them in tissues for days. Applying Zman-seq resolved cell-state and molecular trajectories of the dysfunctional immune microenvironment in glioblastoma. Within 24 hours of tumor infiltration, cytotoxic natural killer cells transitioned to a dysfunctional program regulated by TGFB1 signaling. Infiltrating monocytes differentiated into immunosuppressive macrophages, characterized by the upregulation of suppressive myeloid checkpoints Trem2, Il18bp, and Arg1, over 36 to 48 hours. Treatment with an antagonistic anti-TREM2 antibody reshaped the tumor microenvironment by redirecting the monocyte trajectory toward pro-inflammatory macrophages. Zman-seq is a broadly applicable technology, enabling empirical measurements of differentiation trajectories, which can enhance the development of more efficacious immunotherapies.

Tripokin: A multi-specific immunocytokine for cancer immunotherapy.

Antibodies that target the tumor microenvironment can be used to deliver pro-inflammatory payloads, such as cytokines. Cytokines are small proteins able to modulate the activity of the immune system, and antibody-cytokine fusion proteins have been tested in preclinical and clinical settings. In this study, we describe Tripokin, a novel multi-specific fusion protein that combines interleukin-2 and a single amino acid mutant of tumor necrosis factor. The two pro-inflammatory payloads were fused to the L19 antibody, a clinical-grade antibody against the extradomain B of fibronectin. The human payloads were used for clinical applications, while the corresponding murine cytokines were used for preclinical studies. The resulting fusion proteins were produced in mammalian cells and purified to homogeneity. The murine Tripokin product was well tolerated in tumor-bearing mice at three doses of 30 µg in a 2-day interval and promoted rapid tumor eradication in murine models, more efficiently than single-agent immunocytokines. Tripokin induced rapid tumor necrosis and stimulated a robust immune response, impacting innate and adaptive immune pathways. In addition, the combination with immune checkpoint inhibitors further boosted the therapeutic efficacy of our molecule. Tripokin represents a promising clinical candidate for the simultaneous delivery of interleukin-2 and tumor necrosis factor to neoplastic sites.

Identification, Organic Synthesis, and Sensitive Analysis of a cis-Homosalate-Specific Exposure Biomarker.

Homosalate (HMS) is an organic UV filter used in sunscreens and personal care products. Despite its widespread use and detection in environmental matrices, little is known regarding its exposure in humans. HMS is used as a mixture of cis- and trans-isomers, and we recently revealed major differences in human toxicokinetics, indicating the need to consider these isomers separately in exposure and risk assessments. In the course of these previous investigations of human HMS toxicokinetics, we identified two trans-HMS-specific and one cis-HMS-specific biomarker candidates. However, the latter lacks sensitivity due to only low amounts excreted in urine, prompting the search for another cis-HMS-specific biomarker. Our toxicokinetic investigations revealed a total of five isomers of HMS carboxylic acid metabolites (HMS-CA). Of these, only one was specifically formed from cis-HMS (HMS-CA 5), but its full identity in terms of constitution and configuration had, so far, not been elucidated. Here, we describe the synthesis of three HMS-CA isomers, of which the isomer (1R,3S,5S)/(1S,3R,5R)-3-((2-hydroxybenzoyl)oxy)-1,5-dimethylcyclohexane-1-carboxylic acid turned out to be HMS-CA 5. Taken together with two previously synthesized HMS-CA isomers, we were able to identify the constitution and configuration of all five HMS-CA isomers observed in human metabolism. We integrated the newly identified cis-HMS-specific metabolite HMS-CA 5 into our previously published human biomonitoring LC-MS/MS method. Intra- and interday precisions had coefficients of variation below 2% and 5%, respectively, and the mean relative recovery was 96%. The limit of quantification in urine was 0.02 µg L-1, enabling the quantification of HMS-CA 5 in urine samples for at least 96 h after sunscreen application. The extended method thus enables the sensitive and separate monitoring of cis- and trans-HMS in future human biomonitoring studies for exposure and risk assessment.

Toxicokinetics of homosalate in humans after dermal application: applicability of oral-route data for exposure assessment by human biomonitoring.

Homosalate (HMS) is a UV filter used in sunscreens and personal care products as a mixture of cis- and trans-isomers. Systemic absorption after sunscreen use has been demonstrated in humans, and concerns have been raised about possible endocrine activity of HMS, making a general population exposure assessment desirable. In a previous study, it was shown that the oral bioavailability of cis-HMS (cHMS) is lower than that of trans-HMS (tHMS) by a factor of 10, calling for a separate evaluation of both isomers in exposure and risk assessment. The aim of the current study is the investigation of HMS toxicokinetics after dermal exposure. Four volunteers applied a commercial sunscreen containing 10% HMS to their whole body under regular-use conditions (18-40 mg HMS (kg bw)-1). Parent HMS isomers and hydroxylated and carboxylic acid metabolites were quantified using authentic standards and isotope dilution analysis. Further metabolites were investigated semi-quantitatively. Elimination was delayed and slower compared to the oral route, and terminal elimination half-times were around 24 h. After dermal exposure, the bioavailability of cHMS was a factor of 2 lower than that of tHMS. However, metabolite ratios in relation to the respective parent isomer were very similar to the oral route, supporting the applicability of the oral-route urinary excretion fractions for dermal-route exposure assessments. Exemplary calculations of intake doses showed margins of safety between 11 and 92 (depending on the approach) after single whole-body sunscreen application. Human biomonitoring can reliably quantify oral and dermal HMS exposures and support the monitoring of exposure reduction measures.

[Immunotherapy against gliomas]. / Immuntherapie gegen Gliome.

BACKGROUND: Gliomas represent the most frequent malignant primary brain tumors in adults. Despite multimodal treatment concepts involving surgery, irradiation and chemotherapy, the prognosis remains poor and they are incurable. Recent insights into the interactions between the immune system and the central nervous system as well as breakthroughs in the results of other cancer types have led to the fact that various immunotherapeutic approaches against gliomas have also been investigated and in some cases specifically developed. OBJECTIVE: This article provides an overview of the current status of different immunotherapeutic concepts against gliomas, highlighting the advantages, disadvantages, and challenges. Additionally, it provides an overview of currently ongoing immunotherapeutic clinical trials in Germany and neighboring countries. RESULTS: Previous randomized studies on antibodies against programmed cell death protein 1 (anti-PD1) immune checkpoint inhibition, viral treatment and peptide vaccination targeting the variant III of the epidermal growth factor receptor (EGFRvIII) in glioblastomas were negative with respect to survival benefits. Conversely, other immunotherapeutic approaches, such as multivalent or driver mutation-based vaccinations, cytokine-based therapy and cell therapy, demonstrated a robust scientific foundation, with at least early studies showing promising safety and pharmacodynamic effects on the tumors. DISCUSSION: Currently, immunotherapies against gliomas should only be applied within the framework of well-designed clinical studies. There are still many knowledge gaps regarding the mechanisms of action and resistance of various immunotherapies. Accompanying translational research is essential to address these gaps and develop more effective therapies.

Ultrahigh-Throughput, Real-Time Flow Cytometry for Rare Cell Quantification from Whole Blood.

We present an ultrahigh-throughput, real-time fluorescence cytometer comprising a viscoelastic microfluidic system and a complementary metal-oxide-semiconductor (CMOS) linear image sensor-based detection system. The flow cytometer allows for real-time quantification of a variety of fluorescence species, including micrometer-sized particles and cells, at analytical throughputs in excess of 400,000 species per second. The platform integrates a custom C++ control program and graphical user interface (GUI) to allow for the processing of raw signals, adjustment of processing parameters, and display of fluorescence intensity histograms in real time. To demonstrate the efficacy of the platform for rare event detection and its utility as a basic clinical tool, we measure and quantify patient-derived circulating tumor cells (CTCs) in peripheral blood, realizing that detection has a sensitivity of 6 CTCs per million blood cells (0.000006%) with a volumetric throughput of over 3 mL/min.

Biomonitoring of volatile organic compounds and organophosphorus flame retardands in commercial aircrews after "fume and smell events".

Health risks to humans after "fume and smell events", short-term incidents on aircrafts that are accompanied by unpleasant odour or visible smoke, remain a subject of controversy. We assessed exposure to volatile organic compounds (VOC) and organophosphorus compounds (OPC) by biomonitoring in 375 aircrew members after self-reported "fume and smell events" and in 88 persons of the general population. A total of 20 parameters were analysed in blood and urine by gas chromatography and mass spectrometry. Median levels of acetone in blood and urine and 2-propanol in blood were elevated in aircrews compared to controls (p < 0.0001). Additionally, elevated peak exposures, best estimated by the 95th percentiles, were observed in aircrews for n-heptane and n-octane in blood, and acetone, 2,5-hexanedione and o-cresol in urine. Only the maximum observed levels of 2,5-hexandione in urine (768 µg/L) and toluene in blood (77 µg/L) in aircrew members were higher than the current biological exposure indices (BEI® levels) (500 and 20 µg/L, respectively) of the American Conference of Governmental Industrial Hygienists (US-ACGIH) for workers occupationally exposed to n-hexane and toluene, two well-accepted human neurotoxicants. Low-level exposures to n-hexane and toluene could be also observed in controls. The majority of OPC parameters in urine, including those of neurotoxic ortho-isomers of tricresylphosphate, were below the limit of quantitation in both aircrews and controls. Our comparative VOC and OPC analyses in biological samples of a large number of aircrew members and controls suggest that exposures are similar in both groups and generally low.

Genetic profiles of oligometastatic non-small-cell lung cancer and corresponding brain metastases.

OBJECTIVES: In patients with oligometastatic non-small-cell lung cancer (NSCLC), systemic therapy in combination with local ablative treatment of the primary tumour and all metastatic sites is associated with improved prognosis. For patient selection and treatment allocation, further knowledge about the molecular characteristics of the oligometastatic state is necessary. Here, we performed a genetic characterization of primary NSCLC and corresponding brain metastases (BM). METHODS: We retrospectively identified patients with oligometastatic NSCLC and synchronous (<3 months) or metachronous (>3 months) BM who underwent surgical resection of both primary tumour and BM. Mutation profiling of formalin-fixed paraffin-embedded tumour cell blocks was performed by targeted next-generation sequencing using the Oncomine Focus Assay panel. RESULTS: Sequencing was successful in 46 paired samples. An oncogenic alteration was present in 31 primary tumours (67.4%) and 40 BM (86.9%). The alteration of the primary tumours was preserved in the corresponding BM in 29 out of 31 cases (93.5%). The most prevalent oncogenic driver in both primary tumours and BM was a KRAS (Kirsten rat sarcoma viral oncogene) mutation (s = 21). In 16 patients (34.8%), the BM harboured additional oncogenic alterations. The presence of a private genetic alteration in the BM was an independent predictor of shorter overall survival. CONCLUSIONS: In oligometastatic NSCLC, BM retain the main genetic alterations of the primary tumours. Patients may profit from targeted inhibition of mutated KRAS. Additional private genetic alterations in the BM are dismal.

Synthetic mRNAs Containing Minimalistic Untranslated Regions Are Highly Functional In Vitro and In Vivo.

Synthetic mRNA produced by in vitro transcription (ivt mRNA) is the active pharmaceutical ingredient of approved anti-COVID-19 vaccines and of many drugs under development. Such synthetic mRNA typically contains several hundred bases of non-coding "untranslated" regions (UTRs) that are involved in the stabilization and translation of the mRNA. However, UTRs are often complex structures, which may complicate the entire production process. To eliminate this obstacle, we managed to reduce the total amount of nucleotides in the UTRs to only four bases. In this way, we generate minimal ivt mRNA ("minRNA"), which is less complex than the usual optimized ivt mRNAs that are contained, for example, in approved vaccines. We have compared the efficacy of minRNA to common augmented mRNAs (with UTRs of globin genes or those included in licensed vaccines) in vivo and in vitro and could demonstrate equivalent functionalities. Our minimal mRNA design will facilitate the further development and implementation of ivt mRNA-based vaccines and therapies.

A novel strategy to generate immunocytokines with activity-on-demand using small molecule inhibitors.

Cytokine-based therapeutics have been shown to mediate objective responses in certain tumor entities but suffer from insufficient selectivity, causing limiting toxicity which prevents dose escalation to therapeutically active regimens. The antibody-based delivery of cytokines significantly increases the therapeutic index of the corresponding payload but still suffers from side effects associated with peak concentrations of the product in blood upon intravenous administration. Here we devise a general strategy (named "Intra-Cork") to mask systemic cytokine activity without impacting anti-cancer efficacy. Our technology features the use of antibody-cytokine fusions, capable of selective localization at the neoplastic site, in combination with pathway-selective inhibitors of the cytokine signaling, which rapidly clear from the body. This strategy, exemplified with a tumor-targeted IL12 in combination with a JAK2 inhibitor, allowed to abrogate cytokine-driven toxicity without affecting therapeutic activity in a preclinical model of cancer. This approach is readily applicable in clinical practice.

An IL-7 fusion protein targeting EDA fibronectin upregulates TCF1 on CD8+ T-cells, preferentially accumulates to neoplastic lesions, and boosts PD-1 blockade.

BACKGROUND: Anti-PD-1 antibodies have revolutionized cancer immunotherapy due to their ability to induce long-lasting complete remissions in a proportion of patients. Current research efforts are attempting to identify biomarkers and suitable combination partners to predict or further improve the activity of immune checkpoint inhibitors. Antibody-cytokine fusions are a class of pharmaceuticals that showed the potential to boost the anticancer properties of other immunotherapies. Extradomain A-fibronectin (EDA-FN), which is expressed in most solid and hematological tumors but is virtually undetectable in healthy adult tissues, is an attractive target for the delivery of cytokine at the site of the disease. METHODS: In this work, we describe the generation and characterization of a novel interleukin-7-based fusion protein targeting EDA-FN termed F8(scDb)-IL7. The product consists of the F8 antibody specific to the alternatively spliced EDA of FN in the single-chain diabody (scDb) format fused to human IL-7. RESULTS: F8(scDb)-IL7 efficiently stimulates human peripheral blood mononuclear cells in vitro. Moreover, the product significantly increases the expression of T Cell Factor 1 (TCF-1) on CD8+T cells compared with an IL2-fusion protein. TCF-1 has emerged as a pivotal transcription factor that influences the durability and potency of immune responses against tumors. In preclinical cancer models, F8(scDb)-IL7 demonstrates potent single-agent activity and eradicates sarcoma lesions when combined with anti-PD-1. CONCLUSIONS: Our results provide the rationale to explore the combination of F8(scDb)-IL7 with anti-PD-1 antibodies for the treatment of patients with cancer.

A prognostic neural epigenetic signature in high-grade glioma.

Neural-tumor interactions drive glioma growth as evidenced in preclinical models, but clinical validation is limited. We present an epigenetically defined neural signature of glioblastoma that independently predicts patients' survival. We use reference signatures of neural cells to deconvolve tumor DNA and classify samples into low- or high-neural tumors. High-neural glioblastomas exhibit hypomethylated CpG sites and upregulation of genes associated with synaptic integration. Single-cell transcriptomic analysis reveals a high abundance of malignant stemcell-like cells in high-neural glioblastoma, primarily of the neural lineage. These cells are further classified as neural-progenitor-cell-like, astrocyte-like and oligodendrocyte-progenitor-like, alongside oligodendrocytes and excitatory neurons. In line with these findings, high-neural glioblastoma cells engender neuron-to-glioma synapse formation in vitro and in vivo and show an unfavorable survival after xenografting. In patients, a high-neural signature is associated with decreased overall and progression-free survival. High-neural tumors also exhibit increased functional connectivity in magnetencephalography and resting-state magnet resonance imaging and can be detected via DNA analytes and brain-derived neurotrophic factor in patients' plasma. The prognostic importance of the neural signature was further validated in patients diagnosed with diffuse midline glioma. Our study presents an epigenetically defined malignant neural signature in high-grade gliomas that is prognostically relevant. High-neural gliomas likely require a maximized surgical resection approach for improved outcomes.

The Epigenetic Evolution of Glioma Is Determined by the IDH1 Mutation Status and Treatment Regimen.

Tumor adaptation or selection is thought to underlie therapy resistance in glioma. To investigate longitudinal epigenetic evolution of gliomas in response to therapeutic pressure, we performed an epigenomic analysis of 132 matched initial and recurrent tumors from patients with IDH-wildtype (IDHwt) and IDH-mutant (IDHmut) glioma. IDHwt gliomas showed a stable epigenome over time with relatively low levels of global methylation. The epigenome of IDHmut gliomas showed initial high levels of genome-wide DNA methylation that was progressively reduced to levels similar to those of IDHwt tumors. Integration of epigenomics, gene expression, and functional genomics identified HOXD13 as a master regulator of IDHmut astrocytoma evolution. Furthermore, relapse of IDHmut tumors was accompanied by histologic progression that was associated with survival, as validated in an independent cohort. Finally, the initial cell composition of the tumor microenvironment varied between IDHwt and IDHmut tumors and changed differentially following treatment, suggesting increased neoangiogenesis and T-cell infiltration upon treatment of IDHmut gliomas. This study provides one of the largest cohorts of paired longitudinal glioma samples with epigenomic, transcriptomic, and genomic profiling and suggests that treatment of IDHmut glioma is associated with epigenomic evolution toward an IDHwt-like phenotype. SIGNIFICANCE: Standard treatments are related to loss of DNA methylation in IDHmut glioma, resulting in epigenetic activation of genes associated with tumor progression and alterations in the microenvironment that resemble treatment-naïve IDHwt glioma.

Biomonitoring of polycyclic aromatic hydrocarbons in firefighters at fire training facilities and in employees at respiratory protection and hose workshops.

Introduction: Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic to humans and are formed by incomplete combustion. PAHs are always present during firefighting operations, and fire department members can be exposed to them in the workplace. Methods: In this study, we analyzed 1-hydroxypyrene (1-OHP) in 36 urine samples from nine firefighters, collected before and after fire training sessions, and 32 urine samples from eight employees at respiratory protection and hose workshops. To assess breakthrough PAH exposure through personal protective equipment and potential dermal uptake, some of the workshop employees wore cotton garments under their regular workwear. Cotton samples were then examined for the presence of 17 semi-volatile and low-volatility PAHs. Results: After firefighting exercises, we observed approximately a fivefold increase in mean 1-OHP concentrations in samples from firefighters, from 0.24 µg/L to 1.17 µg/L (maximum: 5.31 µg/L). In contrast, 1-OHP levels in workshop employees were found to be low, with the majority of urine samples yielding concentrations below the limit of quantification (LOQ: 0.05 µg/L, maximum: 0.11 µg/L). Similarly, low PAH levels were found on the workshop employees' cotton undergarments, with maximum concentrations of 250 and 205 ng/g for pyrene and benzo[a]pyrene, respectively. Discussion: In conclusion, significant increases in 1-OHP in urine were observed in firefighters after training sessions, whereas work-related exposure remained low among workshop employees.