Diagnostic biomarkers from proteomic characterization of cerebrospinal fluid in patients with brain malignancies.

Recent technological advances in molecular diagnostics through liquid biopsies hold the promise to repetitively monitor tumor evolution and treatment response of brain malignancies without the need of invasive surgical tissue accrual. Here, we implemented a mass spectrometry-based protein analysis pipeline which identified hundreds of proteins in 251 cerebrospinal fluid (CSF) samples from patients with four types of brain malignancies (glioblastoma, lymphoma, brain metastasis, and leptomeningeal disease [LMD]) and from healthy individuals with a focus on glioblastoma in a retrospective and confirmatory prospective observational study. CSF proteome deregulation via disruption of the blood brain barrier appeared to be largely conserved across brain tumor entities. CSF analysis of glioblastoma patients identified two proteomic clusters that correlated with tumor size and patient survival. By integrating CSF data with proteomic analyses of matching glioblastoma tumor tissue and primary glioblastoma cells, we identified potential CSF biomarkers for glioblastoma, in particular chitinase-3-like protein 1 (CHI3L1) and glial fibrillary acidic protein (GFAP). Key findings were validated in a prospective cohort consisting of 35 glioma patients. Finally, in LMD patients who frequently undergo repeated CSF work-up, we explored our proteomic pipeline as a mean to profile consecutive CSF samples. Therefore, proteomic analysis of CSF in brain malignancies has the potential to reveal biomarkers for diagnosis and therapy monitoring.

Cerebrospinal fluid proteomic profiling in nusinersen-treated patients with spinal muscular atrophy.

Promising results from recent clinical trials on the approved antisense oligonucleotide nusinersen in pediatric patients with 5q-linked spinal muscular atrophy (SMA) still have to be confirmed in adult patients but are hindered by a lack of sensitive biomarkers that indicate an early therapeutic response. Changes in the overall neurochemical composition of cerebrospinal fluid (CSF) under therapy may yield additive diagnostic and predictive information. With this prospective proof-of-concept and feasibility study, we evaluated non-targeted CSF proteomic profiles by mass spectrometry along with basic CSF parameters of 10 adult patients with SMA types 2 or 3 before and after 10 months of nusinersen therapy, in comparison with 10 age- and gender-matched controls. These data were analyzed by bioinformatics and correlated with clinical outcomes assessed by the Hammersmith Functional Rating Scale Expanded (HFMSE). CSF proteomic profiles of SMA patients differed from controls. Two groups of SMA patients were identified based on unsupervised clustering. These groups differed in age and expression of proteins related to neurodegeneration and neuroregeneration. Intraindividual CSF differences in response to nusinersen treatment varied between patients who clinically improved and those who did not. Data are available via ProteomeXchange with identifier PXD016757. Comparative CSF proteomic analysis in adult SMA patients before and after treatment with nusinersen-identified subgroups and treatment-related changes and may therefore be suitable for diagnostic and predictive analyses.

Unraveling T-cell Exhaustion: Genetic Screening Meets In Vitro Modeling.

T-cell exhaustion poses a significant barrier to the efficacy of immunotherapies. In the past decade, immune checkpoint blockade (ICB) has been the leading strategy to prevent or reverse T-cell exhaustion. Although ICB yields promising clinical outcomes in patients with cancer, its impact on T-cell reinvigoration is often short-lived. High-throughput genomic tools, including CRISPR screening along with single-cell RNA and chromatin accessibility sequencing may point toward new therapeutic avenues. However, their utility in identifying key mediators of T-cell exhaustion is constrained by the restricted scalability of well-validated in vivo exhaustion models, like chronic LCMV infection. In a recent article in Science Immunology, Wu and colleagues introduce an in vitro exhaustion model that involves repetitive stimulation of T-cell receptor-transgenic, LCMV-specific P14 CD8 T cells. This approach enables a direct comparison of exhausted T (Tex) cells generated both in vivo and in vitro using the same antigen, adeptly pinpointing exhaustion features that can be recapitulated in vitro. Leveraging this efficient and scalable model alongside CRISPR screening, the authors highlight the transcription factor BHLHE40 as a pivotal element in promoting Tex-cell transition from progenitor to intermediate Tex cells.

Deletion of SNX9 alleviates CD8 T cell exhaustion for effective cellular cancer immunotherapy.

Tumor-specific T cells are frequently exhausted by chronic antigenic stimulation. We here report on a human antigen-specific ex vivo model to explore new therapeutic options for T cell immunotherapies. T cells generated with this model resemble tumor-infiltrating exhausted T cells on a phenotypic and transcriptional level. Using a targeted pooled CRISPR-Cas9 screen and individual gene knockout validation experiments, we uncover sorting nexin-9 (SNX9) as a mediator of T cell exhaustion. Upon TCR/CD28 stimulation, deletion of SNX9 in CD8 T cells decreases PLCγ1, Ca2+, and NFATc2-mediated T cell signaling and reduces expression of NR4A1/3 and TOX. SNX9 knockout enhances memory differentiation and IFNγ secretion of adoptively transferred T cells and results in improved anti-tumor efficacy of human chimeric antigen receptor T cells in vivo. Our findings highlight that targeting SNX9 is a strategy to prevent T cell exhaustion and enhance anti-tumor immunity.

Clinical value of diagnostic instruments for ruling out acute coronary syndrome in patients with chest pain: a systematic review.

BACKGROUND: Acute chest pain is a frequent reason to attend an emergency room, and various instruments for calculating the probability of an acute coronary syndrome exist. OBJECTIVE: To assess the safety and efficiency of all available instruments investigated in sample validation studies. METHODS: A systematic review was conducted. Studies were identified describing the development of instruments and all subsequent validations in electronic databases and reference lists of included studies. Inclusion was screened for, full papers checked and data extracted on salient clinical features, performance characteristics and quality in duplicate. RESULTS: Of 20 derivation studies, 10 were at least validated once in 14 validations including 26,488 patients. One study by Selker and colleagues was validated in six new patient series and studies by Goldman et al and the Kennedy et al were both validated in three new patient series. All other studies were validated less than three times. In four out of six validations of the Selker et al study, the sensitivity of the prediction rule was 98% or higher. The corresponding values for specificity ranged from 4% to 34%. All remaining prediction rules showed sensitivity values below 95% in all validations. CONCLUSIONS: No instrument assisting clinicians in the diagnostic investigation of patients with suspected acute coronary syndrome consistently fulfils the safety requirements of clinicians.

Interleukin-2 signals converge in a lymphoid-dendritic cell pathway that promotes anticancer immunity.

Tumor-infiltrating dendritic cells (DCs) correlate with effective anticancer immunity and improved responsiveness to anti-PD-1 checkpoint immunotherapy. However, the drivers of DC expansion and intratumoral accumulation are ill-defined. We found that interleukin-2 (IL-2) stimulated DC formation through innate and adaptive lymphoid cells in mice and humans, and this increase in DCs improved anticancer immunity. Administration of IL-2 to humans within a clinical trial and of IL-2 receptor (IL-2R)-biased IL-2 to mice resulted in pronounced expansion of type 1 DCs, including migratory and cross-presenting subsets, and type 2 DCs, although neither DC precursors nor mature DCs had functional IL-2Rs. In mechanistic studies, IL-2 signals stimulated innate lymphoid cells, natural killer cells, and T cells to synthesize the cytokines FLT3L, CSF-2, and TNF. These cytokines redundantly caused DC expansion and activation, which resulted in improved antigen processing and correlated with favorable anticancer responses in mice and patients. Thus, IL-2 immunotherapy-mediated stimulation of DCs contributes to anticancer immunity by rendering tumors more immunogenic.

Synthesis of a lithium-cyclopentadienide complex by addition of LiNTf2 to a zwitterionic fulvalene.

The synthesis of a η5-coordinated LiCp complex by simple addition of a Li-salt in benzene is presented. A strongly zwitterionic fulvalene serves as the Cp-precursor. Evidence for the coordination of Li+ was obtained by the characterisitic 7Li NMR chemical shifts, variable temperature experiments in solution and by X-ray structure analysis in the solid state.